1 /*
2 * Copyright (c) 1994, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package java.lang;
26
27 import java.io.BufferedInputStream;
28 import java.io.BufferedOutputStream;
29 import java.io.Console;
30 import java.io.FileDescriptor;
31 import java.io.FileInputStream;
32 import java.io.FileOutputStream;
33 import java.io.IOException;
34 import java.io.InputStream;
35 import java.io.OutputStream;
36 import java.io.PrintStream;
37 import java.lang.annotation.Annotation;
38 import java.lang.foreign.MemorySegment;
39 import java.lang.invoke.MethodHandle;
40 import java.lang.invoke.MethodType;
41 import java.lang.invoke.StringConcatFactory;
42 import java.lang.module.ModuleDescriptor;
43 import java.lang.reflect.Constructor;
44 import java.lang.reflect.Executable;
45 import java.lang.reflect.Method;
46 import java.lang.reflect.Modifier;
47 import java.net.URI;
48 import java.net.URL;
49 import java.nio.channels.Channel;
50 import java.nio.channels.spi.SelectorProvider;
51 import java.nio.charset.CharacterCodingException;
52 import java.nio.charset.Charset;
53 import java.security.AccessControlContext;
54 import java.security.AccessController;
55 import java.security.CodeSource;
56 import java.security.PrivilegedAction;
57 import java.security.ProtectionDomain;
58 import java.util.Collections;
59 import java.util.List;
60 import java.util.Locale;
61 import java.util.Map;
62 import java.util.Objects;
63 import java.util.Properties;
64 import java.util.PropertyPermission;
65 import java.util.ResourceBundle;
66 import java.util.Set;
67 import java.util.WeakHashMap;
68 import java.util.function.Supplier;
69 import java.util.concurrent.ConcurrentHashMap;
70 import java.util.stream.Stream;
71
72 import jdk.internal.javac.Restricted;
73 import jdk.internal.logger.LoggerFinderLoader.TemporaryLoggerFinder;
74 import jdk.internal.misc.Blocker;
75 import jdk.internal.misc.CarrierThreadLocal;
76 import jdk.internal.misc.Unsafe;
77 import jdk.internal.util.StaticProperty;
78 import jdk.internal.module.ModuleBootstrap;
79 import jdk.internal.module.ServicesCatalog;
80 import jdk.internal.reflect.CallerSensitive;
81 import jdk.internal.reflect.Reflection;
82 import jdk.internal.access.JavaLangAccess;
83 import jdk.internal.access.SharedSecrets;
84 import jdk.internal.logger.LoggerFinderLoader;
85 import jdk.internal.logger.LazyLoggers;
86 import jdk.internal.logger.LocalizedLoggerWrapper;
87 import jdk.internal.misc.VM;
88 import jdk.internal.util.SystemProps;
89 import jdk.internal.vm.Continuation;
90 import jdk.internal.vm.ContinuationScope;
91 import jdk.internal.vm.StackableScope;
92 import jdk.internal.vm.ThreadContainer;
93 import jdk.internal.vm.annotation.IntrinsicCandidate;
94 import jdk.internal.vm.annotation.Stable;
95 import sun.nio.fs.DefaultFileSystemProvider;
96 import sun.reflect.annotation.AnnotationType;
97 import sun.nio.ch.Interruptible;
98 import sun.nio.cs.UTF_8;
99 import sun.security.util.SecurityConstants;
100
101 /**
102 * The {@code System} class contains several useful class fields
103 * and methods. It cannot be instantiated.
104 *
105 * Among the facilities provided by the {@code System} class
106 * are standard input, standard output, and error output streams;
107 * access to externally defined properties and environment
108 * variables; a means of loading files and libraries; and a utility
109 * method for quickly copying a portion of an array.
110 *
111 * @since 1.0
112 */
113 public final class System {
114 /* Register the natives via the static initializer.
115 *
116 * The VM will invoke the initPhase1 method to complete the initialization
117 * of this class separate from <clinit>.
118 */
119 private static native void registerNatives();
120 static {
121 registerNatives();
122 }
123
124 /** Don't let anyone instantiate this class */
125 private System() {
126 }
127
128 /**
129 * The "standard" input stream. This stream is already
130 * open and ready to supply input data. Typically this stream
131 * corresponds to keyboard input or another input source specified by
132 * the host environment or user. In case this stream is wrapped
133 * in a {@link java.io.InputStreamReader}, {@link Console#charset()}
134 * should be used for the charset, or consider using
135 * {@link Console#reader()}.
136 *
137 * @see Console#charset()
138 * @see Console#reader()
139 */
140 public static final InputStream in = null;
141
142 /**
143 * The "standard" output stream. This stream is already
144 * open and ready to accept output data. Typically this stream
145 * corresponds to display output or another output destination
146 * specified by the host environment or user. The encoding used
147 * in the conversion from characters to bytes is equivalent to
148 * {@link Console#charset()} if the {@code Console} exists,
149 * <a href="#stdout.encoding">stdout.encoding</a> otherwise.
150 * <p>
151 * For simple stand-alone Java applications, a typical way to write
152 * a line of output data is:
153 * <blockquote><pre>
154 * System.out.println(data)
155 * </pre></blockquote>
156 * <p>
157 * See the {@code println} methods in class {@code PrintStream}.
158 *
159 * @see java.io.PrintStream#println()
160 * @see java.io.PrintStream#println(boolean)
161 * @see java.io.PrintStream#println(char)
162 * @see java.io.PrintStream#println(char[])
163 * @see java.io.PrintStream#println(double)
164 * @see java.io.PrintStream#println(float)
165 * @see java.io.PrintStream#println(int)
166 * @see java.io.PrintStream#println(long)
167 * @see java.io.PrintStream#println(java.lang.Object)
168 * @see java.io.PrintStream#println(java.lang.String)
169 * @see Console#charset()
170 * @see <a href="#stdout.encoding">stdout.encoding</a>
171 */
172 public static final PrintStream out = null;
173
174 /**
175 * The "standard" error output stream. This stream is already
176 * open and ready to accept output data.
177 * <p>
178 * Typically this stream corresponds to display output or another
179 * output destination specified by the host environment or user. By
180 * convention, this output stream is used to display error messages
181 * or other information that should come to the immediate attention
182 * of a user even if the principal output stream, the value of the
183 * variable {@code out}, has been redirected to a file or other
184 * destination that is typically not continuously monitored.
185 * The encoding used in the conversion from characters to bytes is
186 * equivalent to {@link Console#charset()} if the {@code Console}
187 * exists, <a href="#stderr.encoding">stderr.encoding</a> otherwise.
188 *
189 * @see Console#charset()
190 * @see <a href="#stderr.encoding">stderr.encoding</a>
191 */
192 public static final PrintStream err = null;
193
194 // Initial values of System.in and System.err, set in initPhase1().
195 private static @Stable InputStream initialIn;
196 private static @Stable PrintStream initialErr;
197
198 // indicates if a security manager is possible
199 private static final int NEVER = 1;
200 private static final int MAYBE = 2;
201 private static @Stable int allowSecurityManager;
202
203 // current security manager
204 @SuppressWarnings("removal")
205 private static volatile SecurityManager security; // read by VM
206
207 // `sun.jnu.encoding` if it is not supported. Otherwise null.
208 // It is initialized in `initPhase1()` before any charset providers
209 // are initialized.
210 private static String notSupportedJnuEncoding;
211
212 // return true if a security manager is allowed
213 private static boolean allowSecurityManager() {
214 return (allowSecurityManager != NEVER);
215 }
216
217 /**
218 * Reassigns the "standard" input stream.
219 *
220 * First, if there is a security manager, its {@code checkPermission}
221 * method is called with a {@code RuntimePermission("setIO")} permission
222 * to see if it's ok to reassign the "standard" input stream.
223 *
224 * @param in the new standard input stream.
225 *
226 * @throws SecurityException
227 * if a security manager exists and its
228 * {@code checkPermission} method doesn't allow
229 * reassigning of the standard input stream.
230 *
231 * @see SecurityManager#checkPermission
232 * @see java.lang.RuntimePermission
233 *
234 * @since 1.1
235 */
236 public static void setIn(InputStream in) {
237 checkIO();
238 setIn0(in);
239 }
240
241 /**
242 * Reassigns the "standard" output stream.
243 *
244 * First, if there is a security manager, its {@code checkPermission}
245 * method is called with a {@code RuntimePermission("setIO")} permission
246 * to see if it's ok to reassign the "standard" output stream.
247 *
248 * @param out the new standard output stream
249 *
250 * @throws SecurityException
251 * if a security manager exists and its
252 * {@code checkPermission} method doesn't allow
253 * reassigning of the standard output stream.
254 *
255 * @see SecurityManager#checkPermission
256 * @see java.lang.RuntimePermission
257 *
258 * @since 1.1
259 */
260 public static void setOut(PrintStream out) {
261 checkIO();
262 setOut0(out);
263 }
264
265 /**
266 * Reassigns the "standard" error output stream.
267 *
268 * First, if there is a security manager, its {@code checkPermission}
269 * method is called with a {@code RuntimePermission("setIO")} permission
270 * to see if it's ok to reassign the "standard" error output stream.
271 *
272 * @param err the new standard error output stream.
273 *
274 * @throws SecurityException
275 * if a security manager exists and its
276 * {@code checkPermission} method doesn't allow
277 * reassigning of the standard error output stream.
278 *
279 * @see SecurityManager#checkPermission
280 * @see java.lang.RuntimePermission
281 *
282 * @since 1.1
283 */
284 public static void setErr(PrintStream err) {
285 checkIO();
286 setErr0(err);
287 }
288
289 private static volatile Console cons;
290
291 /**
292 * Returns the unique {@link java.io.Console Console} object associated
293 * with the current Java virtual machine, if any.
294 *
295 * @return The system console, if any, otherwise {@code null}.
296 *
297 * @since 1.6
298 */
299 public static Console console() {
300 Console c;
301 if ((c = cons) == null) {
302 synchronized (System.class) {
303 if ((c = cons) == null) {
304 cons = c = SharedSecrets.getJavaIOAccess().console();
305 }
306 }
307 }
308 return c;
309 }
310
311 /**
312 * Returns the channel inherited from the entity that created this
313 * Java virtual machine.
314 *
315 * This method returns the channel obtained by invoking the
316 * {@link java.nio.channels.spi.SelectorProvider#inheritedChannel
317 * inheritedChannel} method of the system-wide default
318 * {@link java.nio.channels.spi.SelectorProvider} object.
319 *
320 * <p> In addition to the network-oriented channels described in
321 * {@link java.nio.channels.spi.SelectorProvider#inheritedChannel
322 * inheritedChannel}, this method may return other kinds of
323 * channels in the future.
324 *
325 * @return The inherited channel, if any, otherwise {@code null}.
326 *
327 * @throws IOException
328 * If an I/O error occurs
329 *
330 * @throws SecurityException
331 * If a security manager is present and it does not
332 * permit access to the channel.
333 *
334 * @since 1.5
335 */
336 public static Channel inheritedChannel() throws IOException {
337 return SelectorProvider.provider().inheritedChannel();
338 }
339
340 private static void checkIO() {
341 @SuppressWarnings("removal")
342 SecurityManager sm = getSecurityManager();
343 if (sm != null) {
344 sm.checkPermission(new RuntimePermission("setIO"));
345 }
346 }
347
348 private static native void setIn0(InputStream in);
349 private static native void setOut0(PrintStream out);
350 private static native void setErr0(PrintStream err);
351
352 private static class CallersHolder {
353 // Remember callers of setSecurityManager() here so that warning
354 // is only printed once for each different caller
355 static final Map<Class<?>, Boolean> callers
356 = Collections.synchronizedMap(new WeakHashMap<>());
357 }
358
359 static URL codeSource(Class<?> clazz) {
360 PrivilegedAction<ProtectionDomain> pa = clazz::getProtectionDomain;
361 @SuppressWarnings("removal")
362 CodeSource cs = AccessController.doPrivileged(pa).getCodeSource();
363 return (cs != null) ? cs.getLocation() : null;
364 }
365
366 /**
367 * Sets the system-wide security manager.
368 *
369 * If there is a security manager already installed, this method first
370 * calls the security manager's {@code checkPermission} method
371 * with a {@code RuntimePermission("setSecurityManager")}
372 * permission to ensure it's ok to replace the existing
373 * security manager.
374 * This may result in throwing a {@code SecurityException}.
375 *
376 * <p> Otherwise, the argument is established as the current
377 * security manager. If the argument is {@code null} and no
378 * security manager has been established, then no action is taken and
379 * the method simply returns.
380 *
381 * @implNote In the JDK implementation, if the Java virtual machine is
382 * started with the system property {@code java.security.manager} not set or set to
383 * the special token "{@code disallow}" then the {@code setSecurityManager}
384 * method cannot be used to set a security manager. See the following
385 * <a href="SecurityManager.html#set-security-manager">section of the
386 * {@code SecurityManager} class specification</a> for more details.
387 *
388 * @param sm the security manager or {@code null}
389 * @throws SecurityException
390 * if the security manager has already been set and its {@code
391 * checkPermission} method doesn't allow it to be replaced
392 * @throws UnsupportedOperationException
393 * if {@code sm} is non-null and a security manager is not allowed
394 * to be set dynamically
395 * @see #getSecurityManager
396 * @see SecurityManager#checkPermission
397 * @see java.lang.RuntimePermission
398 * @deprecated This method is only useful in conjunction with
399 * {@linkplain SecurityManager the Security Manager}, which is
400 * deprecated and subject to removal in a future release.
401 * Consequently, this method is also deprecated and subject to
402 * removal. There is no replacement for the Security Manager or this
403 * method.
404 */
405 @Deprecated(since="17", forRemoval=true)
406 @CallerSensitive
407 public static void setSecurityManager(@SuppressWarnings("removal") SecurityManager sm) {
408 if (allowSecurityManager()) {
409 var callerClass = Reflection.getCallerClass();
410 if (CallersHolder.callers.putIfAbsent(callerClass, true) == null) {
411 URL url = codeSource(callerClass);
412 final String source;
413 if (url == null) {
414 source = callerClass.getName();
415 } else {
416 source = callerClass.getName() + " (" + url + ")";
417 }
418 initialErr.printf("""
419 WARNING: A terminally deprecated method in java.lang.System has been called
420 WARNING: System::setSecurityManager has been called by %s
421 WARNING: Please consider reporting this to the maintainers of %s
422 WARNING: System::setSecurityManager will be removed in a future release
423 """, source, callerClass.getName());
424 }
425 implSetSecurityManager(sm);
426 } else {
427 // security manager not allowed
428 if (sm != null) {
429 throw new UnsupportedOperationException(
430 "The Security Manager is deprecated and will be removed in a future release");
431 }
432 }
433 }
434
435 private static void implSetSecurityManager(@SuppressWarnings("removal") SecurityManager sm) {
436 if (security == null) {
437 // ensure image reader is initialized
438 Object.class.getResource("java/lang/ANY");
439 // ensure the default file system is initialized
440 DefaultFileSystemProvider.theFileSystem();
441 }
442 if (sm != null) {
443 try {
444 // pre-populates the SecurityManager.packageAccess cache
445 // to avoid recursive permission checking issues with custom
446 // SecurityManager implementations
447 sm.checkPackageAccess("java.lang");
448 } catch (Exception e) {
449 // no-op
450 }
451 }
452 setSecurityManager0(sm);
453 }
454
455 @SuppressWarnings("removal")
456 private static synchronized
457 void setSecurityManager0(final SecurityManager s) {
458 SecurityManager sm = getSecurityManager();
459 if (sm != null) {
460 // ask the currently installed security manager if we
461 // can replace it.
462 sm.checkPermission(new RuntimePermission("setSecurityManager"));
463 }
464
465 if ((s != null) && (s.getClass().getClassLoader() != null)) {
466 // New security manager class is not on bootstrap classpath.
467 // Force policy to get initialized before we install the new
468 // security manager, in order to prevent infinite loops when
469 // trying to initialize the policy (which usually involves
470 // accessing some security and/or system properties, which in turn
471 // calls the installed security manager's checkPermission method
472 // which will loop infinitely if there is a non-system class
473 // (in this case: the new security manager class) on the stack).
474 AccessController.doPrivileged(new PrivilegedAction<>() {
475 public Object run() {
476 s.getClass().getProtectionDomain().implies
477 (SecurityConstants.ALL_PERMISSION);
478 return null;
479 }
480 });
481 }
482
483 security = s;
484 }
485
486 /**
487 * Gets the system-wide security manager.
488 *
489 * @return if a security manager has already been established for the
490 * current application, then that security manager is returned;
491 * otherwise, {@code null} is returned.
492 * @see #setSecurityManager
493 * @deprecated This method is only useful in conjunction with
494 * {@linkplain SecurityManager the Security Manager}, which is
495 * deprecated and subject to removal in a future release.
496 * Consequently, this method is also deprecated and subject to
497 * removal. There is no replacement for the Security Manager or this
498 * method.
499 */
500 @SuppressWarnings("removal")
501 @Deprecated(since="17", forRemoval=true)
502 public static SecurityManager getSecurityManager() {
503 if (allowSecurityManager()) {
504 return security;
505 } else {
506 return null;
507 }
508 }
509
510 /**
511 * Returns the current time in milliseconds. Note that
512 * while the unit of time of the return value is a millisecond,
513 * the granularity of the value depends on the underlying
514 * operating system and may be larger. For example, many
515 * operating systems measure time in units of tens of
516 * milliseconds.
517 *
518 * <p> See the description of the class {@code Date} for
519 * a discussion of slight discrepancies that may arise between
520 * "computer time" and coordinated universal time (UTC).
521 *
522 * @return the difference, measured in milliseconds, between
523 * the current time and midnight, January 1, 1970 UTC.
524 * @see java.util.Date
525 */
526 @IntrinsicCandidate
527 public static native long currentTimeMillis();
528
529 /**
530 * Returns the current value of the running Java Virtual Machine's
531 * high-resolution time source, in nanoseconds.
532 *
533 * This method can only be used to measure elapsed time and is
534 * not related to any other notion of system or wall-clock time.
535 * The value returned represents nanoseconds since some fixed but
536 * arbitrary <i>origin</i> time (perhaps in the future, so values
537 * may be negative). The same origin is used by all invocations of
538 * this method in an instance of a Java virtual machine; other
539 * virtual machine instances are likely to use a different origin.
540 *
541 * <p>This method provides nanosecond precision, but not necessarily
542 * nanosecond resolution (that is, how frequently the value changes)
543 * - no guarantees are made except that the resolution is at least as
544 * good as that of {@link #currentTimeMillis()}.
545 *
546 * <p>Differences in successive calls that span greater than
547 * approximately 292 years (2<sup>63</sup> nanoseconds) will not
548 * correctly compute elapsed time due to numerical overflow.
549 *
550 * <p>The values returned by this method become meaningful only when
551 * the difference between two such values, obtained within the same
552 * instance of a Java virtual machine, is computed.
553 *
554 * <p>For example, to measure how long some code takes to execute:
555 * <pre> {@code
556 * long startTime = System.nanoTime();
557 * // ... the code being measured ...
558 * long elapsedNanos = System.nanoTime() - startTime;}</pre>
559 *
560 * <p>To compare elapsed time against a timeout, use <pre> {@code
561 * if (System.nanoTime() - startTime >= timeoutNanos) ...}</pre>
562 * instead of <pre> {@code
563 * if (System.nanoTime() >= startTime + timeoutNanos) ...}</pre>
564 * because of the possibility of numerical overflow.
565 *
566 * @return the current value of the running Java Virtual Machine's
567 * high-resolution time source, in nanoseconds
568 * @since 1.5
569 */
570 @IntrinsicCandidate
571 public static native long nanoTime();
572
573 /**
574 * Copies an array from the specified source array, beginning at the
575 * specified position, to the specified position of the destination array.
576 * A subsequence of array components are copied from the source
577 * array referenced by {@code src} to the destination array
578 * referenced by {@code dest}. The number of components copied is
579 * equal to the {@code length} argument. The components at
580 * positions {@code srcPos} through
581 * {@code srcPos+length-1} in the source array are copied into
582 * positions {@code destPos} through
583 * {@code destPos+length-1}, respectively, of the destination
584 * array.
585 * <p>
586 * If the {@code src} and {@code dest} arguments refer to the
587 * same array object, then the copying is performed as if the
588 * components at positions {@code srcPos} through
589 * {@code srcPos+length-1} were first copied to a temporary
590 * array with {@code length} components and then the contents of
591 * the temporary array were copied into positions
592 * {@code destPos} through {@code destPos+length-1} of the
593 * destination array.
594 * <p>
595 * If {@code dest} is {@code null}, then a
596 * {@code NullPointerException} is thrown.
597 * <p>
598 * If {@code src} is {@code null}, then a
599 * {@code NullPointerException} is thrown and the destination
600 * array is not modified.
601 * <p>
602 * Otherwise, if any of the following is true, an
603 * {@code ArrayStoreException} is thrown and the destination is
604 * not modified:
605 * <ul>
606 * <li>The {@code src} argument refers to an object that is not an
607 * array.
608 * <li>The {@code dest} argument refers to an object that is not an
609 * array.
610 * <li>The {@code src} argument and {@code dest} argument refer
611 * to arrays whose component types are different primitive types.
612 * <li>The {@code src} argument refers to an array with a primitive
613 * component type and the {@code dest} argument refers to an array
614 * with a reference component type.
615 * <li>The {@code src} argument refers to an array with a reference
616 * component type and the {@code dest} argument refers to an array
617 * with a primitive component type.
618 * </ul>
619 * <p>
620 * Otherwise, if any of the following is true, an
621 * {@code IndexOutOfBoundsException} is
622 * thrown and the destination is not modified:
623 * <ul>
624 * <li>The {@code srcPos} argument is negative.
625 * <li>The {@code destPos} argument is negative.
626 * <li>The {@code length} argument is negative.
627 * <li>{@code srcPos+length} is greater than
628 * {@code src.length}, the length of the source array.
629 * <li>{@code destPos+length} is greater than
630 * {@code dest.length}, the length of the destination array.
631 * </ul>
632 * <p>
633 * Otherwise, if any actual component of the source array from
634 * position {@code srcPos} through
635 * {@code srcPos+length-1} cannot be converted to the component
636 * type of the destination array by assignment conversion, an
637 * {@code ArrayStoreException} is thrown. In this case, let
638 * <b><i>k</i></b> be the smallest nonnegative integer less than
639 * length such that {@code src[srcPos+}<i>k</i>{@code ]}
640 * cannot be converted to the component type of the destination
641 * array; when the exception is thrown, source array components from
642 * positions {@code srcPos} through
643 * {@code srcPos+}<i>k</i>{@code -1}
644 * will already have been copied to destination array positions
645 * {@code destPos} through
646 * {@code destPos+}<i>k</I>{@code -1} and no other
647 * positions of the destination array will have been modified.
648 * (Because of the restrictions already itemized, this
649 * paragraph effectively applies only to the situation where both
650 * arrays have component types that are reference types.)
651 *
652 * @param src the source array.
653 * @param srcPos starting position in the source array.
654 * @param dest the destination array.
655 * @param destPos starting position in the destination data.
656 * @param length the number of array elements to be copied.
657 * @throws IndexOutOfBoundsException if copying would cause
658 * access of data outside array bounds.
659 * @throws ArrayStoreException if an element in the {@code src}
660 * array could not be stored into the {@code dest} array
661 * because of a type mismatch.
662 * @throws NullPointerException if either {@code src} or
663 * {@code dest} is {@code null}.
664 */
665 @IntrinsicCandidate
666 public static native void arraycopy(Object src, int srcPos,
667 Object dest, int destPos,
668 int length);
669
670 /**
671 * Returns the same hash code for the given object as
672 * would be returned by the default method hashCode(),
673 * whether or not the given object's class overrides
674 * hashCode().
675 * The hash code for the null reference is zero.
676 *
677 * @param x object for which the hashCode is to be calculated
678 * @return the hashCode
679 * @since 1.1
680 * @see Object#hashCode
681 * @see java.util.Objects#hashCode(Object)
682 */
683 @IntrinsicCandidate
684 public static native int identityHashCode(Object x);
685
686 /**
687 * System properties.
688 *
689 * See {@linkplain #getProperties getProperties} for details.
690 */
691 private static Properties props;
692
693 /**
694 * Determines the current system properties.
695 *
696 * First, if there is a security manager, its
697 * {@code checkPropertiesAccess} method is called with no
698 * arguments. This may result in a security exception.
699 * <p>
700 * The current set of system properties for use by the
701 * {@link #getProperty(String)} method is returned as a
702 * {@code Properties} object. If there is no current set of
703 * system properties, a set of system properties is first created and
704 * initialized. This set of system properties includes a value
705 * for each of the following keys unless the description of the associated
706 * value indicates that the value is optional.
707 * <table class="striped" style="text-align:left">
708 * <caption style="display:none">Shows property keys and associated values</caption>
709 * <thead>
710 * <tr><th scope="col">Key</th>
711 * <th scope="col">Description of Associated Value</th></tr>
712 * </thead>
713 * <tbody>
714 * <tr><th scope="row">{@systemProperty java.version}</th>
715 * <td>Java Runtime Environment version, which may be interpreted
716 * as a {@link Runtime.Version}</td></tr>
717 * <tr><th scope="row">{@systemProperty java.version.date}</th>
718 * <td>Java Runtime Environment version date, in ISO-8601 YYYY-MM-DD
719 * format, which may be interpreted as a {@link
720 * java.time.LocalDate}</td></tr>
721 * <tr><th scope="row">{@systemProperty java.vendor}</th>
722 * <td>Java Runtime Environment vendor</td></tr>
723 * <tr><th scope="row">{@systemProperty java.vendor.url}</th>
724 * <td>Java vendor URL</td></tr>
725 * <tr><th scope="row">{@systemProperty java.vendor.version}</th>
726 * <td>Java vendor version <em>(optional)</em> </td></tr>
727 * <tr><th scope="row">{@systemProperty java.home}</th>
728 * <td>Java installation directory</td></tr>
729 * <tr><th scope="row">{@systemProperty java.vm.specification.version}</th>
730 * <td>Java Virtual Machine specification version, whose value is the
731 * {@linkplain Runtime.Version#feature feature} element of the
732 * {@linkplain Runtime#version() runtime version}</td></tr>
733 * <tr><th scope="row">{@systemProperty java.vm.specification.vendor}</th>
734 * <td>Java Virtual Machine specification vendor</td></tr>
735 * <tr><th scope="row">{@systemProperty java.vm.specification.name}</th>
736 * <td>Java Virtual Machine specification name</td></tr>
737 * <tr><th scope="row">{@systemProperty java.vm.version}</th>
738 * <td>Java Virtual Machine implementation version which may be
739 * interpreted as a {@link Runtime.Version}</td></tr>
740 * <tr><th scope="row">{@systemProperty java.vm.vendor}</th>
741 * <td>Java Virtual Machine implementation vendor</td></tr>
742 * <tr><th scope="row">{@systemProperty java.vm.name}</th>
743 * <td>Java Virtual Machine implementation name</td></tr>
744 * <tr><th scope="row">{@systemProperty java.specification.version}</th>
745 * <td>Java Runtime Environment specification version, whose value is
746 * the {@linkplain Runtime.Version#feature feature} element of the
747 * {@linkplain Runtime#version() runtime version}</td></tr>
748 * <tr><th scope="row">{@systemProperty java.specification.maintenance.version}</th>
749 * <td>Java Runtime Environment specification maintenance version,
750 * may be interpreted as a positive integer <em>(optional, see below)</em></td></tr>
751 * <tr><th scope="row">{@systemProperty java.specification.vendor}</th>
752 * <td>Java Runtime Environment specification vendor</td></tr>
753 * <tr><th scope="row">{@systemProperty java.specification.name}</th>
754 * <td>Java Runtime Environment specification name</td></tr>
755 * <tr><th scope="row">{@systemProperty java.class.version}</th>
756 * <td>{@linkplain java.lang.reflect.ClassFileFormatVersion#latest() Latest}
757 * Java class file format version recognized by the Java runtime as {@code "MAJOR.MINOR"}
758 * where {@link java.lang.reflect.ClassFileFormatVersion#major() MAJOR} and {@code MINOR}
759 * are both formatted as decimal integers</td></tr>
760 * <tr><th scope="row">{@systemProperty java.class.path}</th>
761 * <td>Java class path (refer to
762 * {@link ClassLoader#getSystemClassLoader()} for details)</td></tr>
763 * <tr><th scope="row">{@systemProperty java.library.path}</th>
764 * <td>List of paths to search when loading libraries</td></tr>
765 * <tr><th scope="row">{@systemProperty java.io.tmpdir}</th>
766 * <td>Default temp file path</td></tr>
767 * <tr><th scope="row">{@systemProperty os.name}</th>
768 * <td>Operating system name</td></tr>
769 * <tr><th scope="row">{@systemProperty os.arch}</th>
770 * <td>Operating system architecture</td></tr>
771 * <tr><th scope="row">{@systemProperty os.version}</th>
772 * <td>Operating system version</td></tr>
773 * <tr><th scope="row">{@systemProperty file.separator}</th>
774 * <td>File separator ("/" on UNIX)</td></tr>
775 * <tr><th scope="row">{@systemProperty path.separator}</th>
776 * <td>Path separator (":" on UNIX)</td></tr>
777 * <tr><th scope="row">{@systemProperty line.separator}</th>
778 * <td>Line separator ("\n" on UNIX)</td></tr>
779 * <tr><th scope="row">{@systemProperty user.name}</th>
780 * <td>User's account name</td></tr>
781 * <tr><th scope="row">{@systemProperty user.home}</th>
782 * <td>User's home directory</td></tr>
783 * <tr><th scope="row">{@systemProperty user.dir}</th>
784 * <td>User's current working directory</td></tr>
785 * <tr><th scope="row">{@systemProperty native.encoding}</th>
786 * <td>Character encoding name derived from the host environment and/or
787 * the user's settings. Setting this system property has no effect.</td></tr>
788 * <tr><th scope="row">{@systemProperty stdout.encoding}</th>
789 * <td>Character encoding name for {@link System#out System.out}.
790 * The Java runtime can be started with the system property set to {@code UTF-8},
791 * starting it with the property set to another value leads to undefined behavior.
792 * <tr><th scope="row">{@systemProperty stderr.encoding}</th>
793 * <td>Character encoding name for {@link System#err System.err}.
794 * The Java runtime can be started with the system property set to {@code UTF-8},
795 * starting it with the property set to another value leads to undefined behavior.
796 * </tbody>
797 * </table>
798 * <p>
799 * The {@code java.specification.maintenance.version} property is
800 * defined if the specification implemented by this runtime at the
801 * time of its construction had undergone a <a
802 * href="https://jcp.org/en/procedures/jcp2#3.6.4">maintenance
803 * release</a>. When defined, its value identifies that
804 * maintenance release. To indicate the first maintenance release
805 * this property will have the value {@code "1"}, to indicate the
806 * second maintenance release this property will have the value
807 * {@code "2"}, and so on.
808 * <p>
809 * Multiple paths in a system property value are separated by the path
810 * separator character of the platform.
811 * <p>
812 * Note that even if the security manager does not permit the
813 * {@code getProperties} operation, it may choose to permit the
814 * {@link #getProperty(String)} operation.
815 * <p>
816 * Additional locale-related system properties defined by the
817 * {@link Locale##default_locale Default Locale} section in the {@code Locale}
818 * class description may also be obtained with this method.
819 *
820 * @apiNote
821 * <strong>Changing a standard system property may have unpredictable results
822 * unless otherwise specified.</strong>
823 * Property values may be cached during initialization or on first use.
824 * Setting a standard property after initialization using {@link #getProperties()},
825 * {@link #setProperties(Properties)}, {@link #setProperty(String, String)}, or
826 * {@link #clearProperty(String)} may not have the desired effect.
827 *
828 * @implNote
829 * In addition to the standard system properties, the system
830 * properties may include the following keys:
831 * <table class="striped">
832 * <caption style="display:none">Shows property keys and associated values</caption>
833 * <thead>
834 * <tr><th scope="col">Key</th>
835 * <th scope="col">Description of Associated Value</th></tr>
836 * </thead>
837 * <tbody>
838 * <tr><th scope="row">{@systemProperty jdk.module.path}</th>
839 * <td>The application module path</td></tr>
840 * <tr><th scope="row">{@systemProperty jdk.module.upgrade.path}</th>
841 * <td>The upgrade module path</td></tr>
842 * <tr><th scope="row">{@systemProperty jdk.module.main}</th>
843 * <td>The module name of the initial/main module</td></tr>
844 * <tr><th scope="row">{@systemProperty jdk.module.main.class}</th>
845 * <td>The main class name of the initial module</td></tr>
846 * <tr><th scope="row">{@systemProperty file.encoding}</th>
847 * <td>The name of the default charset, defaults to {@code UTF-8}.
848 * The property may be set on the command line to the value
849 * {@code UTF-8} or {@code COMPAT}. If set on the command line to
850 * the value {@code COMPAT} then the value is replaced with the
851 * value of the {@code native.encoding} property during startup.
852 * Setting the property to a value other than {@code UTF-8} or
853 * {@code COMPAT} leads to unspecified behavior.
854 * </td></tr>
855 * </tbody>
856 * </table>
857 *
858 * @return the system properties
859 * @throws SecurityException if a security manager exists and its
860 * {@code checkPropertiesAccess} method doesn't allow access
861 * to the system properties.
862 * @see #setProperties
863 * @see java.lang.SecurityException
864 * @see java.lang.SecurityManager#checkPropertiesAccess()
865 * @see java.util.Properties
866 */
867 public static Properties getProperties() {
868 @SuppressWarnings("removal")
869 SecurityManager sm = getSecurityManager();
870 if (sm != null) {
871 sm.checkPropertiesAccess();
872 }
873
874 return props;
875 }
876
877 /**
878 * Returns the system-dependent line separator string. It always
879 * returns the same value - the initial value of the {@linkplain
880 * #getProperty(String) system property} {@code line.separator}.
881 *
882 * <p>On UNIX systems, it returns {@code "\n"}; on Microsoft
883 * Windows systems it returns {@code "\r\n"}.
884 *
885 * @return the system-dependent line separator string
886 * @since 1.7
887 */
888 public static String lineSeparator() {
889 return lineSeparator;
890 }
891
892 private static String lineSeparator;
893
894 /**
895 * Sets the system properties to the {@code Properties} argument.
896 *
897 * First, if there is a security manager, its
898 * {@code checkPropertiesAccess} method is called with no
899 * arguments. This may result in a security exception.
900 * <p>
901 * The argument becomes the current set of system properties for use
902 * by the {@link #getProperty(String)} method. If the argument is
903 * {@code null}, then the current set of system properties is
904 * forgotten.
905 *
906 * @apiNote
907 * <strong>Changing a standard system property may have unpredictable results
908 * unless otherwise specified</strong>.
909 * See {@linkplain #getProperties getProperties} for details.
910 *
911 * @param props the new system properties.
912 * @throws SecurityException if a security manager exists and its
913 * {@code checkPropertiesAccess} method doesn't allow access
914 * to the system properties.
915 * @see #getProperties
916 * @see java.util.Properties
917 * @see java.lang.SecurityException
918 * @see java.lang.SecurityManager#checkPropertiesAccess()
919 */
920 public static void setProperties(Properties props) {
921 @SuppressWarnings("removal")
922 SecurityManager sm = getSecurityManager();
923 if (sm != null) {
924 sm.checkPropertiesAccess();
925 }
926
927 if (props == null) {
928 Map<String, String> tempProps = SystemProps.initProperties();
929 VersionProps.init(tempProps);
930 props = createProperties(tempProps);
931 }
932 System.props = props;
933 }
934
935 /**
936 * Gets the system property indicated by the specified key.
937 *
938 * First, if there is a security manager, its
939 * {@code checkPropertyAccess} method is called with the key as
940 * its argument. This may result in a SecurityException.
941 * <p>
942 * If there is no current set of system properties, a set of system
943 * properties is first created and initialized in the same manner as
944 * for the {@code getProperties} method.
945 *
946 * @apiNote
947 * <strong>Changing a standard system property may have unpredictable results
948 * unless otherwise specified</strong>.
949 * See {@linkplain #getProperties getProperties} for details.
950 *
951 * @param key the name of the system property.
952 * @return the string value of the system property,
953 * or {@code null} if there is no property with that key.
954 *
955 * @throws SecurityException if a security manager exists and its
956 * {@code checkPropertyAccess} method doesn't allow
957 * access to the specified system property.
958 * @throws NullPointerException if {@code key} is {@code null}.
959 * @throws IllegalArgumentException if {@code key} is empty.
960 * @see #setProperty
961 * @see java.lang.SecurityException
962 * @see java.lang.SecurityManager#checkPropertyAccess(java.lang.String)
963 * @see java.lang.System#getProperties()
964 */
965 public static String getProperty(String key) {
966 checkKey(key);
967 @SuppressWarnings("removal")
968 SecurityManager sm = getSecurityManager();
969 if (sm != null) {
970 sm.checkPropertyAccess(key);
971 }
972
973 return props.getProperty(key);
974 }
975
976 /**
977 * Gets the system property indicated by the specified key.
978 *
979 * First, if there is a security manager, its
980 * {@code checkPropertyAccess} method is called with the
981 * {@code key} as its argument.
982 * <p>
983 * If there is no current set of system properties, a set of system
984 * properties is first created and initialized in the same manner as
985 * for the {@code getProperties} method.
986 *
987 * @param key the name of the system property.
988 * @param def a default value.
989 * @return the string value of the system property,
990 * or the default value if there is no property with that key.
991 *
992 * @throws SecurityException if a security manager exists and its
993 * {@code checkPropertyAccess} method doesn't allow
994 * access to the specified system property.
995 * @throws NullPointerException if {@code key} is {@code null}.
996 * @throws IllegalArgumentException if {@code key} is empty.
997 * @see #setProperty
998 * @see java.lang.SecurityManager#checkPropertyAccess(java.lang.String)
999 * @see java.lang.System#getProperties()
1000 */
1001 public static String getProperty(String key, String def) {
1002 checkKey(key);
1003 @SuppressWarnings("removal")
1004 SecurityManager sm = getSecurityManager();
1005 if (sm != null) {
1006 sm.checkPropertyAccess(key);
1007 }
1008
1009 return props.getProperty(key, def);
1010 }
1011
1012 /**
1013 * Sets the system property indicated by the specified key.
1014 *
1015 * First, if a security manager exists, its
1016 * {@code SecurityManager.checkPermission} method
1017 * is called with a {@code PropertyPermission(key, "write")}
1018 * permission. This may result in a SecurityException being thrown.
1019 * If no exception is thrown, the specified property is set to the given
1020 * value.
1021 *
1022 * @apiNote
1023 * <strong>Changing a standard system property may have unpredictable results
1024 * unless otherwise specified</strong>.
1025 * See {@linkplain #getProperties getProperties} for details.
1026 *
1027 * @param key the name of the system property.
1028 * @param value the value of the system property.
1029 * @return the previous value of the system property,
1030 * or {@code null} if it did not have one.
1031 *
1032 * @throws SecurityException if a security manager exists and its
1033 * {@code checkPermission} method doesn't allow
1034 * setting of the specified property.
1035 * @throws NullPointerException if {@code key} or
1036 * {@code value} is {@code null}.
1037 * @throws IllegalArgumentException if {@code key} is empty.
1038 * @see #getProperty
1039 * @see java.lang.System#getProperty(java.lang.String)
1040 * @see java.lang.System#getProperty(java.lang.String, java.lang.String)
1041 * @see java.util.PropertyPermission
1042 * @see SecurityManager#checkPermission
1043 * @since 1.2
1044 */
1045 public static String setProperty(String key, String value) {
1046 checkKey(key);
1047 @SuppressWarnings("removal")
1048 SecurityManager sm = getSecurityManager();
1049 if (sm != null) {
1050 sm.checkPermission(new PropertyPermission(key,
1051 SecurityConstants.PROPERTY_WRITE_ACTION));
1052 }
1053
1054 return (String) props.setProperty(key, value);
1055 }
1056
1057 /**
1058 * Removes the system property indicated by the specified key.
1059 *
1060 * First, if a security manager exists, its
1061 * {@code SecurityManager.checkPermission} method
1062 * is called with a {@code PropertyPermission(key, "write")}
1063 * permission. This may result in a SecurityException being thrown.
1064 * If no exception is thrown, the specified property is removed.
1065 *
1066 * @apiNote
1067 * <strong>Changing a standard system property may have unpredictable results
1068 * unless otherwise specified</strong>.
1069 * See {@linkplain #getProperties getProperties} method for details.
1070 *
1071 * @param key the name of the system property to be removed.
1072 * @return the previous string value of the system property,
1073 * or {@code null} if there was no property with that key.
1074 *
1075 * @throws SecurityException if a security manager exists and its
1076 * {@code checkPropertyAccess} method doesn't allow
1077 * access to the specified system property.
1078 * @throws NullPointerException if {@code key} is {@code null}.
1079 * @throws IllegalArgumentException if {@code key} is empty.
1080 * @see #getProperty
1081 * @see #setProperty
1082 * @see java.util.Properties
1083 * @see java.lang.SecurityException
1084 * @see java.lang.SecurityManager#checkPropertiesAccess()
1085 * @since 1.5
1086 */
1087 public static String clearProperty(String key) {
1088 checkKey(key);
1089 @SuppressWarnings("removal")
1090 SecurityManager sm = getSecurityManager();
1091 if (sm != null) {
1092 sm.checkPermission(new PropertyPermission(key, "write"));
1093 }
1094
1095 return (String) props.remove(key);
1096 }
1097
1098 private static void checkKey(String key) {
1099 if (key == null) {
1100 throw new NullPointerException("key can't be null");
1101 }
1102 if (key.isEmpty()) {
1103 throw new IllegalArgumentException("key can't be empty");
1104 }
1105 }
1106
1107 /**
1108 * Gets the value of the specified environment variable. An
1109 * environment variable is a system-dependent external named
1110 * value.
1111 *
1112 * <p>If a security manager exists, its
1113 * {@link SecurityManager#checkPermission checkPermission}
1114 * method is called with a
1115 * {@link RuntimePermission RuntimePermission("getenv."+name)}
1116 * permission. This may result in a {@link SecurityException}
1117 * being thrown. If no exception is thrown the value of the
1118 * variable {@code name} is returned.
1119 *
1120 * <p><a id="EnvironmentVSSystemProperties"><i>System
1121 * properties</i> and <i>environment variables</i></a> are both
1122 * conceptually mappings between names and values. Both
1123 * mechanisms can be used to pass user-defined information to a
1124 * Java process. Environment variables have a more global effect,
1125 * because they are visible to all descendants of the process
1126 * which defines them, not just the immediate Java subprocess.
1127 * They can have subtly different semantics, such as case
1128 * insensitivity, on different operating systems. For these
1129 * reasons, environment variables are more likely to have
1130 * unintended side effects. It is best to use system properties
1131 * where possible. Environment variables should be used when a
1132 * global effect is desired, or when an external system interface
1133 * requires an environment variable (such as {@code PATH}).
1134 *
1135 * <p>On UNIX systems the alphabetic case of {@code name} is
1136 * typically significant, while on Microsoft Windows systems it is
1137 * typically not. For example, the expression
1138 * {@code System.getenv("FOO").equals(System.getenv("foo"))}
1139 * is likely to be true on Microsoft Windows.
1140 *
1141 * @param name the name of the environment variable
1142 * @return the string value of the variable, or {@code null}
1143 * if the variable is not defined in the system environment
1144 * @throws NullPointerException if {@code name} is {@code null}
1145 * @throws SecurityException
1146 * if a security manager exists and its
1147 * {@link SecurityManager#checkPermission checkPermission}
1148 * method doesn't allow access to the environment variable
1149 * {@code name}
1150 * @see #getenv()
1151 * @see ProcessBuilder#environment()
1152 */
1153 public static String getenv(String name) {
1154 @SuppressWarnings("removal")
1155 SecurityManager sm = getSecurityManager();
1156 if (sm != null) {
1157 sm.checkPermission(new RuntimePermission("getenv."+name));
1158 }
1159
1160 return ProcessEnvironment.getenv(name);
1161 }
1162
1163
1164 /**
1165 * Returns an unmodifiable string map view of the current system environment.
1166 * The environment is a system-dependent mapping from names to
1167 * values which is passed from parent to child processes.
1168 *
1169 * <p>If the system does not support environment variables, an
1170 * empty map is returned.
1171 *
1172 * <p>The returned map will never contain null keys or values.
1173 * Attempting to query the presence of a null key or value will
1174 * throw a {@link NullPointerException}. Attempting to query
1175 * the presence of a key or value which is not of type
1176 * {@link String} will throw a {@link ClassCastException}.
1177 *
1178 * <p>The returned map and its collection views may not obey the
1179 * general contract of the {@link Object#equals} and
1180 * {@link Object#hashCode} methods.
1181 *
1182 * <p>The returned map is typically case-sensitive on all platforms.
1183 *
1184 * <p>If a security manager exists, its
1185 * {@link SecurityManager#checkPermission checkPermission}
1186 * method is called with a
1187 * {@link RuntimePermission RuntimePermission("getenv.*")} permission.
1188 * This may result in a {@link SecurityException} being thrown.
1189 *
1190 * <p>When passing information to a Java subprocess,
1191 * <a href=#EnvironmentVSSystemProperties>system properties</a>
1192 * are generally preferred over environment variables.
1193 *
1194 * @return the environment as a map of variable names to values
1195 * @throws SecurityException
1196 * if a security manager exists and its
1197 * {@link SecurityManager#checkPermission checkPermission}
1198 * method doesn't allow access to the process environment
1199 * @see #getenv(String)
1200 * @see ProcessBuilder#environment()
1201 * @since 1.5
1202 */
1203 public static java.util.Map<String,String> getenv() {
1204 @SuppressWarnings("removal")
1205 SecurityManager sm = getSecurityManager();
1206 if (sm != null) {
1207 sm.checkPermission(new RuntimePermission("getenv.*"));
1208 }
1209
1210 return ProcessEnvironment.getenv();
1211 }
1212
1213 /**
1214 * {@code System.Logger} instances log messages that will be
1215 * routed to the underlying logging framework the {@link System.LoggerFinder
1216 * LoggerFinder} uses.
1217 *
1218 * {@code System.Logger} instances are typically obtained from
1219 * the {@link java.lang.System System} class, by calling
1220 * {@link java.lang.System#getLogger(java.lang.String) System.getLogger(loggerName)}
1221 * or {@link java.lang.System#getLogger(java.lang.String, java.util.ResourceBundle)
1222 * System.getLogger(loggerName, bundle)}.
1223 *
1224 * @see java.lang.System#getLogger(java.lang.String)
1225 * @see java.lang.System#getLogger(java.lang.String, java.util.ResourceBundle)
1226 * @see java.lang.System.LoggerFinder
1227 *
1228 * @since 9
1229 */
1230 public interface Logger {
1231
1232 /**
1233 * System {@linkplain Logger loggers} levels.
1234 *
1235 * A level has a {@linkplain #getName() name} and {@linkplain
1236 * #getSeverity() severity}.
1237 * Level values are {@link #ALL}, {@link #TRACE}, {@link #DEBUG},
1238 * {@link #INFO}, {@link #WARNING}, {@link #ERROR}, {@link #OFF},
1239 * by order of increasing severity.
1240 * <br>
1241 * {@link #ALL} and {@link #OFF}
1242 * are simple markers with severities mapped respectively to
1243 * {@link java.lang.Integer#MIN_VALUE Integer.MIN_VALUE} and
1244 * {@link java.lang.Integer#MAX_VALUE Integer.MAX_VALUE}.
1245 * <p>
1246 * <b>Severity values and Mapping to {@code java.util.logging.Level}.</b>
1247 * <p>
1248 * {@linkplain System.Logger.Level System logger levels} are mapped to
1249 * {@linkplain java.logging/java.util.logging.Level java.util.logging levels}
1250 * of corresponding severity.
1251 * <br>The mapping is as follows:
1252 * <br><br>
1253 * <table class="striped">
1254 * <caption>System.Logger Severity Level Mapping</caption>
1255 * <thead>
1256 * <tr><th scope="col">System.Logger Levels</th>
1257 * <th scope="col">java.util.logging Levels</th>
1258 * </thead>
1259 * <tbody>
1260 * <tr><th scope="row">{@link Logger.Level#ALL ALL}</th>
1261 * <td>{@link java.logging/java.util.logging.Level#ALL ALL}</td>
1262 * <tr><th scope="row">{@link Logger.Level#TRACE TRACE}</th>
1263 * <td>{@link java.logging/java.util.logging.Level#FINER FINER}</td>
1264 * <tr><th scope="row">{@link Logger.Level#DEBUG DEBUG}</th>
1265 * <td>{@link java.logging/java.util.logging.Level#FINE FINE}</td>
1266 * <tr><th scope="row">{@link Logger.Level#INFO INFO}</th>
1267 * <td>{@link java.logging/java.util.logging.Level#INFO INFO}</td>
1268 * <tr><th scope="row">{@link Logger.Level#WARNING WARNING}</th>
1269 * <td>{@link java.logging/java.util.logging.Level#WARNING WARNING}</td>
1270 * <tr><th scope="row">{@link Logger.Level#ERROR ERROR}</th>
1271 * <td>{@link java.logging/java.util.logging.Level#SEVERE SEVERE}</td>
1272 * <tr><th scope="row">{@link Logger.Level#OFF OFF}</th>
1273 * <td>{@link java.logging/java.util.logging.Level#OFF OFF}</td>
1274 * </tbody>
1275 * </table>
1276 *
1277 * @since 9
1278 *
1279 * @see java.lang.System.LoggerFinder
1280 * @see java.lang.System.Logger
1281 */
1282 @SuppressWarnings("doclint:reference") // cross-module links
1283 public enum Level {
1284
1285 // for convenience, we're reusing java.util.logging.Level int values
1286 // the mapping logic in sun.util.logging.PlatformLogger depends
1287 // on this.
1288 /**
1289 * A marker to indicate that all levels are enabled.
1290 * This level {@linkplain #getSeverity() severity} is
1291 * {@link Integer#MIN_VALUE}.
1292 */
1293 ALL(Integer.MIN_VALUE), // typically mapped to/from j.u.l.Level.ALL
1294 /**
1295 * {@code TRACE} level: usually used to log diagnostic information.
1296 * This level {@linkplain #getSeverity() severity} is
1297 * {@code 400}.
1298 */
1299 TRACE(400), // typically mapped to/from j.u.l.Level.FINER
1300 /**
1301 * {@code DEBUG} level: usually used to log debug information traces.
1302 * This level {@linkplain #getSeverity() severity} is
1303 * {@code 500}.
1304 */
1305 DEBUG(500), // typically mapped to/from j.u.l.Level.FINEST/FINE/CONFIG
1306 /**
1307 * {@code INFO} level: usually used to log information messages.
1308 * This level {@linkplain #getSeverity() severity} is
1309 * {@code 800}.
1310 */
1311 INFO(800), // typically mapped to/from j.u.l.Level.INFO
1312 /**
1313 * {@code WARNING} level: usually used to log warning messages.
1314 * This level {@linkplain #getSeverity() severity} is
1315 * {@code 900}.
1316 */
1317 WARNING(900), // typically mapped to/from j.u.l.Level.WARNING
1318 /**
1319 * {@code ERROR} level: usually used to log error messages.
1320 * This level {@linkplain #getSeverity() severity} is
1321 * {@code 1000}.
1322 */
1323 ERROR(1000), // typically mapped to/from j.u.l.Level.SEVERE
1324 /**
1325 * A marker to indicate that all levels are disabled.
1326 * This level {@linkplain #getSeverity() severity} is
1327 * {@link Integer#MAX_VALUE}.
1328 */
1329 OFF(Integer.MAX_VALUE); // typically mapped to/from j.u.l.Level.OFF
1330
1331 private final int severity;
1332
1333 private Level(int severity) {
1334 this.severity = severity;
1335 }
1336
1337 /**
1338 * Returns the name of this level.
1339 * @return this level {@linkplain #name()}.
1340 */
1341 public final String getName() {
1342 return name();
1343 }
1344
1345 /**
1346 * Returns the severity of this level.
1347 * A higher severity means a more severe condition.
1348 * @return this level severity.
1349 */
1350 public final int getSeverity() {
1351 return severity;
1352 }
1353 }
1354
1355 /**
1356 * Returns the name of this logger.
1357 *
1358 * @return the logger name.
1359 */
1360 public String getName();
1361
1362 /**
1363 * Checks if a message of the given level would be logged by
1364 * this logger.
1365 *
1366 * @param level the log message level.
1367 * @return {@code true} if the given log message level is currently
1368 * being logged.
1369 *
1370 * @throws NullPointerException if {@code level} is {@code null}.
1371 */
1372 public boolean isLoggable(Level level);
1373
1374 /**
1375 * Logs a message.
1376 *
1377 * @implSpec The default implementation for this method calls
1378 * {@code this.log(level, (ResourceBundle)null, msg, (Object[])null);}
1379 *
1380 * @param level the log message level.
1381 * @param msg the string message (or a key in the message catalog, if
1382 * this logger is a {@link
1383 * LoggerFinder#getLocalizedLogger(java.lang.String,
1384 * java.util.ResourceBundle, java.lang.Module) localized logger});
1385 * can be {@code null}.
1386 *
1387 * @throws NullPointerException if {@code level} is {@code null}.
1388 */
1389 public default void log(Level level, String msg) {
1390 log(level, (ResourceBundle) null, msg, (Object[]) null);
1391 }
1392
1393 /**
1394 * Logs a lazily supplied message.
1395 *
1396 * If the logger is currently enabled for the given log message level
1397 * then a message is logged that is the result produced by the
1398 * given supplier function. Otherwise, the supplier is not operated on.
1399 *
1400 * @implSpec When logging is enabled for the given level, the default
1401 * implementation for this method calls
1402 * {@code this.log(level, (ResourceBundle)null, msgSupplier.get(), (Object[])null);}
1403 *
1404 * @param level the log message level.
1405 * @param msgSupplier a supplier function that produces a message.
1406 *
1407 * @throws NullPointerException if {@code level} is {@code null},
1408 * or {@code msgSupplier} is {@code null}.
1409 */
1410 public default void log(Level level, Supplier<String> msgSupplier) {
1411 Objects.requireNonNull(msgSupplier);
1412 if (isLoggable(Objects.requireNonNull(level))) {
1413 log(level, (ResourceBundle) null, msgSupplier.get(), (Object[]) null);
1414 }
1415 }
1416
1417 /**
1418 * Logs a message produced from the given object.
1419 *
1420 * If the logger is currently enabled for the given log message level then
1421 * a message is logged that, by default, is the result produced from
1422 * calling toString on the given object.
1423 * Otherwise, the object is not operated on.
1424 *
1425 * @implSpec When logging is enabled for the given level, the default
1426 * implementation for this method calls
1427 * {@code this.log(level, (ResourceBundle)null, obj.toString(), (Object[])null);}
1428 *
1429 * @param level the log message level.
1430 * @param obj the object to log.
1431 *
1432 * @throws NullPointerException if {@code level} is {@code null}, or
1433 * {@code obj} is {@code null}.
1434 */
1435 public default void log(Level level, Object obj) {
1436 Objects.requireNonNull(obj);
1437 if (isLoggable(Objects.requireNonNull(level))) {
1438 this.log(level, (ResourceBundle) null, obj.toString(), (Object[]) null);
1439 }
1440 }
1441
1442 /**
1443 * Logs a message associated with a given throwable.
1444 *
1445 * @implSpec The default implementation for this method calls
1446 * {@code this.log(level, (ResourceBundle)null, msg, thrown);}
1447 *
1448 * @param level the log message level.
1449 * @param msg the string message (or a key in the message catalog, if
1450 * this logger is a {@link
1451 * LoggerFinder#getLocalizedLogger(java.lang.String,
1452 * java.util.ResourceBundle, java.lang.Module) localized logger});
1453 * can be {@code null}.
1454 * @param thrown a {@code Throwable} associated with the log message;
1455 * can be {@code null}.
1456 *
1457 * @throws NullPointerException if {@code level} is {@code null}.
1458 */
1459 public default void log(Level level, String msg, Throwable thrown) {
1460 this.log(level, null, msg, thrown);
1461 }
1462
1463 /**
1464 * Logs a lazily supplied message associated with a given throwable.
1465 *
1466 * If the logger is currently enabled for the given log message level
1467 * then a message is logged that is the result produced by the
1468 * given supplier function. Otherwise, the supplier is not operated on.
1469 *
1470 * @implSpec When logging is enabled for the given level, the default
1471 * implementation for this method calls
1472 * {@code this.log(level, (ResourceBundle)null, msgSupplier.get(), thrown);}
1473 *
1474 * @param level one of the log message level identifiers.
1475 * @param msgSupplier a supplier function that produces a message.
1476 * @param thrown a {@code Throwable} associated with log message;
1477 * can be {@code null}.
1478 *
1479 * @throws NullPointerException if {@code level} is {@code null}, or
1480 * {@code msgSupplier} is {@code null}.
1481 */
1482 public default void log(Level level, Supplier<String> msgSupplier,
1483 Throwable thrown) {
1484 Objects.requireNonNull(msgSupplier);
1485 if (isLoggable(Objects.requireNonNull(level))) {
1486 this.log(level, null, msgSupplier.get(), thrown);
1487 }
1488 }
1489
1490 /**
1491 * Logs a message with an optional list of parameters.
1492 *
1493 * @implSpec The default implementation for this method calls
1494 * {@code this.log(level, (ResourceBundle)null, format, params);}
1495 *
1496 * @param level one of the log message level identifiers.
1497 * @param format the string message format in {@link
1498 * java.text.MessageFormat} format, (or a key in the message
1499 * catalog, if this logger is a {@link
1500 * LoggerFinder#getLocalizedLogger(java.lang.String,
1501 * java.util.ResourceBundle, java.lang.Module) localized logger});
1502 * can be {@code null}.
1503 * @param params an optional list of parameters to the message (may be
1504 * none).
1505 *
1506 * @throws NullPointerException if {@code level} is {@code null}.
1507 */
1508 public default void log(Level level, String format, Object... params) {
1509 this.log(level, null, format, params);
1510 }
1511
1512 /**
1513 * Logs a localized message associated with a given throwable.
1514 *
1515 * If the given resource bundle is non-{@code null}, the {@code msg}
1516 * string is localized using the given resource bundle.
1517 * Otherwise the {@code msg} string is not localized.
1518 *
1519 * @param level the log message level.
1520 * @param bundle a resource bundle to localize {@code msg}; can be
1521 * {@code null}.
1522 * @param msg the string message (or a key in the message catalog,
1523 * if {@code bundle} is not {@code null}); can be {@code null}.
1524 * @param thrown a {@code Throwable} associated with the log message;
1525 * can be {@code null}.
1526 *
1527 * @throws NullPointerException if {@code level} is {@code null}.
1528 */
1529 public void log(Level level, ResourceBundle bundle, String msg,
1530 Throwable thrown);
1531
1532 /**
1533 * Logs a message with resource bundle and an optional list of
1534 * parameters.
1535 *
1536 * If the given resource bundle is non-{@code null}, the {@code format}
1537 * string is localized using the given resource bundle.
1538 * Otherwise the {@code format} string is not localized.
1539 *
1540 * @param level the log message level.
1541 * @param bundle a resource bundle to localize {@code format}; can be
1542 * {@code null}.
1543 * @param format the string message format in {@link
1544 * java.text.MessageFormat} format, (or a key in the message
1545 * catalog if {@code bundle} is not {@code null}); can be {@code null}.
1546 * @param params an optional list of parameters to the message (may be
1547 * none).
1548 *
1549 * @throws NullPointerException if {@code level} is {@code null}.
1550 */
1551 public void log(Level level, ResourceBundle bundle, String format,
1552 Object... params);
1553 }
1554
1555 /**
1556 * The {@code LoggerFinder} service is responsible for creating, managing,
1557 * and configuring loggers to the underlying framework it uses.
1558 *
1559 * A logger finder is a concrete implementation of this class that has a
1560 * zero-argument constructor and implements the abstract methods defined
1561 * by this class.
1562 * The loggers returned from a logger finder are capable of routing log
1563 * messages to the logging backend this provider supports.
1564 * A given invocation of the Java Runtime maintains a single
1565 * system-wide LoggerFinder instance that is loaded as follows:
1566 * <ul>
1567 * <li>First it finds any custom {@code LoggerFinder} provider
1568 * using the {@link java.util.ServiceLoader} facility with the
1569 * {@linkplain ClassLoader#getSystemClassLoader() system class
1570 * loader}.</li>
1571 * <li>If no {@code LoggerFinder} provider is found, the system default
1572 * {@code LoggerFinder} implementation will be used.</li>
1573 * </ul>
1574 * <p>
1575 * An application can replace the logging backend
1576 * <i>even when the java.logging module is present</i>, by simply providing
1577 * and declaring an implementation of the {@link LoggerFinder} service.
1578 * <p>
1579 * <b>Default Implementation</b>
1580 * <p>
1581 * The system default {@code LoggerFinder} implementation uses
1582 * {@code java.util.logging} as the backend framework when the
1583 * {@code java.logging} module is present.
1584 * It returns a {@linkplain System.Logger logger} instance
1585 * that will route log messages to a {@link java.logging/java.util.logging.Logger
1586 * java.util.logging.Logger}. Otherwise, if {@code java.logging} is not
1587 * present, the default implementation will return a simple logger
1588 * instance that will route log messages of {@code INFO} level and above to
1589 * the console ({@code System.err}).
1590 * <p>
1591 * <b>Logging Configuration</b>
1592 * <p>
1593 * {@linkplain Logger Logger} instances obtained from the
1594 * {@code LoggerFinder} factory methods are not directly configurable by
1595 * the application. Configuration is the responsibility of the underlying
1596 * logging backend, and usually requires using APIs specific to that backend.
1597 * <p>For the default {@code LoggerFinder} implementation
1598 * using {@code java.util.logging} as its backend, refer to
1599 * {@link java.logging/java.util.logging java.util.logging} for logging configuration.
1600 * For the default {@code LoggerFinder} implementation returning simple loggers
1601 * when the {@code java.logging} module is absent, the configuration
1602 * is implementation dependent.
1603 * <p>
1604 * Usually an application that uses a logging framework will log messages
1605 * through a logger facade defined (or supported) by that framework.
1606 * Applications that wish to use an external framework should log
1607 * through the facade associated with that framework.
1608 * <p>
1609 * A system class that needs to log messages will typically obtain
1610 * a {@link System.Logger} instance to route messages to the logging
1611 * framework selected by the application.
1612 * <p>
1613 * Libraries and classes that only need loggers to produce log messages
1614 * should not attempt to configure loggers by themselves, as that
1615 * would make them dependent from a specific implementation of the
1616 * {@code LoggerFinder} service.
1617 * <p>
1618 * In addition, when a security manager is present, loggers provided to
1619 * system classes should not be directly configurable through the logging
1620 * backend without requiring permissions.
1621 * <br>
1622 * It is the responsibility of the provider of
1623 * the concrete {@code LoggerFinder} implementation to ensure that
1624 * these loggers are not configured by untrusted code without proper
1625 * permission checks, as configuration performed on such loggers usually
1626 * affects all applications in the same Java Runtime.
1627 * <p>
1628 * <b>Message Levels and Mapping to backend levels</b>
1629 * <p>
1630 * A logger finder is responsible for mapping from a {@code
1631 * System.Logger.Level} to a level supported by the logging backend it uses.
1632 * <br>The default LoggerFinder using {@code java.util.logging} as the backend
1633 * maps {@code System.Logger} levels to
1634 * {@linkplain java.logging/java.util.logging.Level java.util.logging} levels
1635 * of corresponding severity - as described in {@link Logger.Level
1636 * Logger.Level}.
1637 *
1638 * @see java.lang.System
1639 * @see java.lang.System.Logger
1640 *
1641 * @since 9
1642 */
1643 @SuppressWarnings("doclint:reference") // cross-module links
1644 public abstract static class LoggerFinder {
1645 /**
1646 * The {@code RuntimePermission("loggerFinder")} is
1647 * necessary to subclass and instantiate the {@code LoggerFinder} class,
1648 * as well as to obtain loggers from an instance of that class.
1649 */
1650 static final RuntimePermission LOGGERFINDER_PERMISSION =
1651 new RuntimePermission("loggerFinder");
1652
1653 /**
1654 * Creates a new instance of {@code LoggerFinder}.
1655 *
1656 * @implNote It is recommended that a {@code LoggerFinder} service
1657 * implementation does not perform any heavy initialization in its
1658 * constructor, in order to avoid possible risks of deadlock or class
1659 * loading cycles during the instantiation of the service provider.
1660 *
1661 * @throws SecurityException if a security manager is present and its
1662 * {@code checkPermission} method doesn't allow the
1663 * {@code RuntimePermission("loggerFinder")}.
1664 */
1665 protected LoggerFinder() {
1666 this(checkPermission());
1667 }
1668
1669 private LoggerFinder(Void unused) {
1670 // nothing to do.
1671 }
1672
1673 private static Void checkPermission() {
1674 @SuppressWarnings("removal")
1675 final SecurityManager sm = System.getSecurityManager();
1676 if (sm != null) {
1677 sm.checkPermission(LOGGERFINDER_PERMISSION);
1678 }
1679 return null;
1680 }
1681
1682 /**
1683 * Returns an instance of {@link Logger Logger}
1684 * for the given {@code module}.
1685 *
1686 * @param name the name of the logger.
1687 * @param module the module for which the logger is being requested.
1688 *
1689 * @return a {@link Logger logger} suitable for use within the given
1690 * module.
1691 * @throws NullPointerException if {@code name} is {@code null} or
1692 * {@code module} is {@code null}.
1693 * @throws SecurityException if a security manager is present and its
1694 * {@code checkPermission} method doesn't allow the
1695 * {@code RuntimePermission("loggerFinder")}.
1696 */
1697 public abstract Logger getLogger(String name, Module module);
1698
1699 /**
1700 * Returns a localizable instance of {@link Logger Logger}
1701 * for the given {@code module}.
1702 * The returned logger will use the provided resource bundle for
1703 * message localization.
1704 *
1705 * @implSpec By default, this method calls {@link
1706 * #getLogger(java.lang.String, java.lang.Module)
1707 * this.getLogger(name, module)} to obtain a logger, then wraps that
1708 * logger in a {@link Logger} instance where all methods that do not
1709 * take a {@link ResourceBundle} as parameter are redirected to one
1710 * which does - passing the given {@code bundle} for
1711 * localization. So for instance, a call to {@link
1712 * Logger#log(Logger.Level, String) Logger.log(Level.INFO, msg)}
1713 * will end up as a call to {@link
1714 * Logger#log(Logger.Level, ResourceBundle, String, Object...)
1715 * Logger.log(Level.INFO, bundle, msg, (Object[])null)} on the wrapped
1716 * logger instance.
1717 * Note however that by default, string messages returned by {@link
1718 * java.util.function.Supplier Supplier<String>} will not be
1719 * localized, as it is assumed that such strings are messages which are
1720 * already constructed, rather than keys in a resource bundle.
1721 * <p>
1722 * An implementation of {@code LoggerFinder} may override this method,
1723 * for example, when the underlying logging backend provides its own
1724 * mechanism for localizing log messages, then such a
1725 * {@code LoggerFinder} would be free to return a logger
1726 * that makes direct use of the mechanism provided by the backend.
1727 *
1728 * @param name the name of the logger.
1729 * @param bundle a resource bundle; can be {@code null}.
1730 * @param module the module for which the logger is being requested.
1731 * @return an instance of {@link Logger Logger} which will use the
1732 * provided resource bundle for message localization.
1733 *
1734 * @throws NullPointerException if {@code name} is {@code null} or
1735 * {@code module} is {@code null}.
1736 * @throws SecurityException if a security manager is present and its
1737 * {@code checkPermission} method doesn't allow the
1738 * {@code RuntimePermission("loggerFinder")}.
1739 */
1740 public Logger getLocalizedLogger(String name, ResourceBundle bundle,
1741 Module module) {
1742 return new LocalizedLoggerWrapper<>(getLogger(name, module), bundle);
1743 }
1744
1745 /**
1746 * Returns the {@code LoggerFinder} instance. There is one
1747 * single system-wide {@code LoggerFinder} instance in
1748 * the Java Runtime. See the class specification of how the
1749 * {@link LoggerFinder LoggerFinder} implementation is located and
1750 * loaded.
1751 *
1752 * @return the {@link LoggerFinder LoggerFinder} instance.
1753 * @throws SecurityException if a security manager is present and its
1754 * {@code checkPermission} method doesn't allow the
1755 * {@code RuntimePermission("loggerFinder")}.
1756 */
1757 public static LoggerFinder getLoggerFinder() {
1758 @SuppressWarnings("removal")
1759 final SecurityManager sm = System.getSecurityManager();
1760 if (sm != null) {
1761 sm.checkPermission(LOGGERFINDER_PERMISSION);
1762 }
1763 return accessProvider();
1764 }
1765
1766
1767 private static volatile LoggerFinder service;
1768 @SuppressWarnings("removal")
1769 static LoggerFinder accessProvider() {
1770 // We do not need to synchronize: LoggerFinderLoader will
1771 // always return the same instance, so if we don't have it,
1772 // just fetch it again.
1773 LoggerFinder finder = service;
1774 if (finder == null) {
1775 PrivilegedAction<LoggerFinder> pa =
1776 () -> LoggerFinderLoader.getLoggerFinder();
1777 finder = AccessController.doPrivileged(pa, null,
1778 LOGGERFINDER_PERMISSION);
1779 if (finder instanceof TemporaryLoggerFinder) return finder;
1780 service = finder;
1781 }
1782 return finder;
1783 }
1784
1785 }
1786
1787
1788 /**
1789 * Returns an instance of {@link Logger Logger} for the caller's
1790 * use.
1791 *
1792 * @implSpec
1793 * Instances returned by this method route messages to loggers
1794 * obtained by calling {@link LoggerFinder#getLogger(java.lang.String,
1795 * java.lang.Module) LoggerFinder.getLogger(name, module)}, where
1796 * {@code module} is the caller's module.
1797 * In cases where {@code System.getLogger} is called from a context where
1798 * there is no caller frame on the stack (e.g when called directly
1799 * from a JNI attached thread), {@code IllegalCallerException} is thrown.
1800 * To obtain a logger in such a context, use an auxiliary class that will
1801 * implicitly be identified as the caller, or use the system {@link
1802 * LoggerFinder#getLoggerFinder() LoggerFinder} to obtain a logger instead.
1803 * Note that doing the latter may eagerly initialize the underlying
1804 * logging system.
1805 *
1806 * @apiNote
1807 * This method may defer calling the {@link
1808 * LoggerFinder#getLogger(java.lang.String, java.lang.Module)
1809 * LoggerFinder.getLogger} method to create an actual logger supplied by
1810 * the logging backend, for instance, to allow loggers to be obtained during
1811 * the system initialization time.
1812 *
1813 * @param name the name of the logger.
1814 * @return an instance of {@link Logger} that can be used by the calling
1815 * class.
1816 * @throws NullPointerException if {@code name} is {@code null}.
1817 * @throws IllegalCallerException if there is no Java caller frame on the
1818 * stack.
1819 *
1820 * @since 9
1821 */
1822 @CallerSensitive
1823 public static Logger getLogger(String name) {
1824 Objects.requireNonNull(name);
1825 final Class<?> caller = Reflection.getCallerClass();
1826 if (caller == null) {
1827 throw new IllegalCallerException("no caller frame");
1828 }
1829 return LazyLoggers.getLogger(name, caller.getModule());
1830 }
1831
1832 /**
1833 * Returns a localizable instance of {@link Logger
1834 * Logger} for the caller's use.
1835 * The returned logger will use the provided resource bundle for message
1836 * localization.
1837 *
1838 * @implSpec
1839 * The returned logger will perform message localization as specified
1840 * by {@link LoggerFinder#getLocalizedLogger(java.lang.String,
1841 * java.util.ResourceBundle, java.lang.Module)
1842 * LoggerFinder.getLocalizedLogger(name, bundle, module)}, where
1843 * {@code module} is the caller's module.
1844 * In cases where {@code System.getLogger} is called from a context where
1845 * there is no caller frame on the stack (e.g when called directly
1846 * from a JNI attached thread), {@code IllegalCallerException} is thrown.
1847 * To obtain a logger in such a context, use an auxiliary class that
1848 * will implicitly be identified as the caller, or use the system {@link
1849 * LoggerFinder#getLoggerFinder() LoggerFinder} to obtain a logger instead.
1850 * Note that doing the latter may eagerly initialize the underlying
1851 * logging system.
1852 *
1853 * @apiNote
1854 * This method is intended to be used after the system is fully initialized.
1855 * This method may trigger the immediate loading and initialization
1856 * of the {@link LoggerFinder} service, which may cause issues if the
1857 * Java Runtime is not ready to initialize the concrete service
1858 * implementation yet.
1859 * System classes which may be loaded early in the boot sequence and
1860 * need to log localized messages should create a logger using
1861 * {@link #getLogger(java.lang.String)} and then use the log methods that
1862 * take a resource bundle as parameter.
1863 *
1864 * @param name the name of the logger.
1865 * @param bundle a resource bundle.
1866 * @return an instance of {@link Logger} which will use the provided
1867 * resource bundle for message localization.
1868 * @throws NullPointerException if {@code name} is {@code null} or
1869 * {@code bundle} is {@code null}.
1870 * @throws IllegalCallerException if there is no Java caller frame on the
1871 * stack.
1872 *
1873 * @since 9
1874 */
1875 @SuppressWarnings("removal")
1876 @CallerSensitive
1877 public static Logger getLogger(String name, ResourceBundle bundle) {
1878 final ResourceBundle rb = Objects.requireNonNull(bundle);
1879 Objects.requireNonNull(name);
1880 final Class<?> caller = Reflection.getCallerClass();
1881 if (caller == null) {
1882 throw new IllegalCallerException("no caller frame");
1883 }
1884 final SecurityManager sm = System.getSecurityManager();
1885 // We don't use LazyLoggers if a resource bundle is specified.
1886 // Bootstrap sensitive classes in the JDK do not use resource bundles
1887 // when logging. This could be revisited later, if it needs to.
1888 if (sm != null) {
1889 final PrivilegedAction<Logger> pa =
1890 () -> LoggerFinder.accessProvider()
1891 .getLocalizedLogger(name, rb, caller.getModule());
1892 return AccessController.doPrivileged(pa, null,
1893 LoggerFinder.LOGGERFINDER_PERMISSION);
1894 }
1895 return LoggerFinder.accessProvider()
1896 .getLocalizedLogger(name, rb, caller.getModule());
1897 }
1898
1899 /**
1900 * Initiates the {@linkplain Runtime##shutdown shutdown sequence} of the Java Virtual Machine.
1901 * Unless the security manager denies exiting, this method initiates the shutdown sequence
1902 * (if it is not already initiated) and then blocks indefinitely. This method neither returns
1903 * nor throws an exception; that is, it does not complete either normally or abruptly.
1904 * <p>
1905 * The argument serves as a status code. By convention, a nonzero status code
1906 * indicates abnormal termination.
1907 * <p>
1908 * The call {@code System.exit(n)} is effectively equivalent to the call:
1909 * {@snippet :
1910 * Runtime.getRuntime().exit(n)
1911 * }
1912 *
1913 * @implNote
1914 * The initiation of the shutdown sequence is logged by {@link Runtime#exit(int)}.
1915 *
1916 * @param status exit status.
1917 * @throws SecurityException
1918 * if a security manager exists and its {@code checkExit} method
1919 * doesn't allow exit with the specified status.
1920 * @see java.lang.Runtime#exit(int)
1921 */
1922 public static void exit(int status) {
1923 Runtime.getRuntime().exit(status);
1924 }
1925
1926 /**
1927 * Runs the garbage collector in the Java Virtual Machine.
1928 * <p>
1929 * Calling the {@code gc} method suggests that the Java Virtual Machine
1930 * expend effort toward recycling unused objects in order to
1931 * make the memory they currently occupy available for reuse
1932 * by the Java Virtual Machine.
1933 * When control returns from the method call, the Java Virtual Machine
1934 * has made a best effort to reclaim space from all unused objects.
1935 * There is no guarantee that this effort will recycle any particular
1936 * number of unused objects, reclaim any particular amount of space, or
1937 * complete at any particular time, if at all, before the method returns or ever.
1938 * There is also no guarantee that this effort will determine
1939 * the change of reachability in any particular number of objects,
1940 * or that any particular number of {@link java.lang.ref.Reference Reference}
1941 * objects will be cleared and enqueued.
1942 *
1943 * <p>
1944 * The call {@code System.gc()} is effectively equivalent to the
1945 * call:
1946 * <blockquote><pre>
1947 * Runtime.getRuntime().gc()
1948 * </pre></blockquote>
1949 *
1950 * @see java.lang.Runtime#gc()
1951 */
1952 public static void gc() {
1953 Runtime.getRuntime().gc();
1954 }
1955
1956 /**
1957 * Runs the finalization methods of any objects pending finalization.
1958 *
1959 * Calling this method suggests that the Java Virtual Machine expend
1960 * effort toward running the {@code finalize} methods of objects
1961 * that have been found to be discarded but whose {@code finalize}
1962 * methods have not yet been run. When control returns from the
1963 * method call, the Java Virtual Machine has made a best effort to
1964 * complete all outstanding finalizations.
1965 * <p>
1966 * The call {@code System.runFinalization()} is effectively
1967 * equivalent to the call:
1968 * <blockquote><pre>
1969 * Runtime.getRuntime().runFinalization()
1970 * </pre></blockquote>
1971 *
1972 * @deprecated Finalization has been deprecated for removal. See
1973 * {@link java.lang.Object#finalize} for background information and details
1974 * about migration options.
1975 * <p>
1976 * When running in a JVM in which finalization has been disabled or removed,
1977 * no objects will be pending finalization, so this method does nothing.
1978 *
1979 * @see java.lang.Runtime#runFinalization()
1980 * @jls 12.6 Finalization of Class Instances
1981 */
1982 @Deprecated(since="18", forRemoval=true)
1983 @SuppressWarnings("removal")
1984 public static void runFinalization() {
1985 Runtime.getRuntime().runFinalization();
1986 }
1987
1988 /**
1989 * Loads the native library specified by the filename argument. The filename
1990 * argument must be an absolute path name.
1991 *
1992 * If the filename argument, when stripped of any platform-specific library
1993 * prefix, path, and file extension, indicates a library whose name is,
1994 * for example, L, and a native library called L is statically linked
1995 * with the VM, then the JNI_OnLoad_L function exported by the library
1996 * is invoked rather than attempting to load a dynamic library.
1997 * A filename matching the argument does not have to exist in the
1998 * file system.
1999 * See the <a href="{@docRoot}/../specs/jni/index.html"> JNI Specification</a>
2000 * for more details.
2001 *
2002 * Otherwise, the filename argument is mapped to a native library image in
2003 * an implementation-dependent manner.
2004 *
2005 * <p>
2006 * The call {@code System.load(name)} is effectively equivalent
2007 * to the call:
2008 * <blockquote><pre>
2009 * Runtime.getRuntime().load(name)
2010 * </pre></blockquote>
2011 *
2012 * @param filename the file to load.
2013 * @throws SecurityException if a security manager exists and its
2014 * {@code checkLink} method doesn't allow
2015 * loading of the specified dynamic library
2016 * @throws UnsatisfiedLinkError if either the filename is not an
2017 * absolute path name, the native library is not statically
2018 * linked with the VM, or the library cannot be mapped to
2019 * a native library image by the host system.
2020 * @throws NullPointerException if {@code filename} is {@code null}
2021 * @throws IllegalCallerException if the caller is in a module that
2022 * does not have native access enabled.
2023 *
2024 * @spec jni/index.html Java Native Interface Specification
2025 * @see java.lang.Runtime#load(java.lang.String)
2026 * @see java.lang.SecurityManager#checkLink(java.lang.String)
2027 */
2028 @CallerSensitive
2029 @Restricted
2030 public static void load(String filename) {
2031 Class<?> caller = Reflection.getCallerClass();
2032 Reflection.ensureNativeAccess(caller, System.class, "load", false);
2033 Runtime.getRuntime().load0(caller, filename);
2034 }
2035
2036 /**
2037 * Loads the native library specified by the {@code libname}
2038 * argument. The {@code libname} argument must not contain any platform
2039 * specific prefix, file extension or path. If a native library
2040 * called {@code libname} is statically linked with the VM, then the
2041 * JNI_OnLoad_{@code libname} function exported by the library is invoked.
2042 * See the <a href="{@docRoot}/../specs/jni/index.html"> JNI Specification</a>
2043 * for more details.
2044 *
2045 * Otherwise, the libname argument is loaded from a system library
2046 * location and mapped to a native library image in an
2047 * implementation-dependent manner.
2048 * <p>
2049 * The call {@code System.loadLibrary(name)} is effectively
2050 * equivalent to the call
2051 * <blockquote><pre>
2052 * Runtime.getRuntime().loadLibrary(name)
2053 * </pre></blockquote>
2054 *
2055 * @param libname the name of the library.
2056 * @throws SecurityException if a security manager exists and its
2057 * {@code checkLink} method doesn't allow
2058 * loading of the specified dynamic library
2059 * @throws UnsatisfiedLinkError if either the libname argument
2060 * contains a file path, the native library is not statically
2061 * linked with the VM, or the library cannot be mapped to a
2062 * native library image by the host system.
2063 * @throws NullPointerException if {@code libname} is {@code null}
2064 * @throws IllegalCallerException if the caller is in a module that
2065 * does not have native access enabled.
2066 *
2067 * @spec jni/index.html Java Native Interface Specification
2068 * @see java.lang.Runtime#loadLibrary(java.lang.String)
2069 * @see java.lang.SecurityManager#checkLink(java.lang.String)
2070 */
2071 @CallerSensitive
2072 @Restricted
2073 public static void loadLibrary(String libname) {
2074 Class<?> caller = Reflection.getCallerClass();
2075 Reflection.ensureNativeAccess(caller, System.class, "loadLibrary", false);
2076 Runtime.getRuntime().loadLibrary0(caller, libname);
2077 }
2078
2079 /**
2080 * Maps a library name into a platform-specific string representing
2081 * a native library.
2082 *
2083 * @param libname the name of the library.
2084 * @return a platform-dependent native library name.
2085 * @throws NullPointerException if {@code libname} is {@code null}
2086 * @see java.lang.System#loadLibrary(java.lang.String)
2087 * @see java.lang.ClassLoader#findLibrary(java.lang.String)
2088 * @since 1.2
2089 */
2090 public static native String mapLibraryName(String libname);
2091
2092 /**
2093 * Create PrintStream for stdout/err based on encoding.
2094 */
2095 private static PrintStream newPrintStream(OutputStream out, String enc) {
2096 if (enc != null) {
2097 return new PrintStream(new BufferedOutputStream(out, 128), true,
2098 Charset.forName(enc, UTF_8.INSTANCE));
2099 }
2100 return new PrintStream(new BufferedOutputStream(out, 128), true);
2101 }
2102
2103 /**
2104 * Logs an exception/error at initialization time to stdout or stderr.
2105 *
2106 * @param printToStderr to print to stderr rather than stdout
2107 * @param printStackTrace to print the stack trace
2108 * @param msg the message to print before the exception, can be {@code null}
2109 * @param e the exception or error
2110 */
2111 private static void logInitException(boolean printToStderr,
2112 boolean printStackTrace,
2113 String msg,
2114 Throwable e) {
2115 if (VM.initLevel() < 1) {
2116 throw new InternalError("system classes not initialized");
2117 }
2118 PrintStream log = (printToStderr) ? err : out;
2119 if (msg != null) {
2120 log.println(msg);
2121 }
2122 if (printStackTrace) {
2123 e.printStackTrace(log);
2124 } else {
2125 log.println(e);
2126 for (Throwable suppressed : e.getSuppressed()) {
2127 log.println("Suppressed: " + suppressed);
2128 }
2129 Throwable cause = e.getCause();
2130 if (cause != null) {
2131 log.println("Caused by: " + cause);
2132 }
2133 }
2134 }
2135
2136 /**
2137 * Create the Properties object from a map - masking out system properties
2138 * that are not intended for public access.
2139 */
2140 private static Properties createProperties(Map<String, String> initialProps) {
2141 Properties properties = new Properties(initialProps.size());
2142 for (var entry : initialProps.entrySet()) {
2143 String prop = entry.getKey();
2144 switch (prop) {
2145 // Do not add private system properties to the Properties
2146 case "sun.nio.MaxDirectMemorySize":
2147 case "sun.nio.PageAlignDirectMemory":
2148 // used by java.lang.Integer.IntegerCache
2149 case "java.lang.Integer.IntegerCache.high":
2150 // used by sun.launcher.LauncherHelper
2151 case "sun.java.launcher.diag":
2152 // used by jdk.internal.loader.ClassLoaders
2153 case "jdk.boot.class.path.append":
2154 break;
2155 default:
2156 properties.put(prop, entry.getValue());
2157 }
2158 }
2159 return properties;
2160 }
2161
2162 /**
2163 * Initialize the system class. Called after thread initialization.
2164 */
2165 private static void initPhase1() {
2166
2167 // register the shared secrets - do this first, since SystemProps.initProperties
2168 // might initialize CharsetDecoders that rely on it
2169 setJavaLangAccess();
2170
2171 // VM might invoke JNU_NewStringPlatform() to set those encoding
2172 // sensitive properties (user.home, user.name, boot.class.path, etc.)
2173 // during "props" initialization.
2174 // The charset is initialized in System.c and does not depend on the Properties.
2175 Map<String, String> tempProps = SystemProps.initProperties();
2176 VersionProps.init(tempProps);
2177
2178 // There are certain system configurations that may be controlled by
2179 // VM options such as the maximum amount of direct memory and
2180 // Integer cache size used to support the object identity semantics
2181 // of autoboxing. Typically, the library will obtain these values
2182 // from the properties set by the VM. If the properties are for
2183 // internal implementation use only, these properties should be
2184 // masked from the system properties.
2185 //
2186 // Save a private copy of the system properties object that
2187 // can only be accessed by the internal implementation.
2188 VM.saveProperties(tempProps);
2189 props = createProperties(tempProps);
2190
2191 // Check if sun.jnu.encoding is supported. If not, replace it with UTF-8.
2192 var jnuEncoding = props.getProperty("sun.jnu.encoding");
2193 if (jnuEncoding == null || !Charset.isSupported(jnuEncoding)) {
2194 notSupportedJnuEncoding = jnuEncoding == null ? "null" : jnuEncoding;
2195 props.setProperty("sun.jnu.encoding", "UTF-8");
2196 }
2197
2198 StaticProperty.javaHome(); // Load StaticProperty to cache the property values
2199
2200 lineSeparator = props.getProperty("line.separator");
2201
2202 FileInputStream fdIn = new In(FileDescriptor.in);
2203 FileOutputStream fdOut = new Out(FileDescriptor.out);
2204 FileOutputStream fdErr = new Out(FileDescriptor.err);
2205 initialIn = new BufferedInputStream(fdIn);
2206 setIn0(initialIn);
2207 // stdout/err.encoding are set when the VM is associated with the terminal,
2208 // thus they are equivalent to Console.charset(), otherwise the encodings
2209 // of those properties default to native.encoding
2210 setOut0(newPrintStream(fdOut, props.getProperty("stdout.encoding")));
2211 initialErr = newPrintStream(fdErr, props.getProperty("stderr.encoding"));
2212 setErr0(initialErr);
2213
2214 // Setup Java signal handlers for HUP, TERM, and INT (where available).
2215 Terminator.setup();
2216
2217 // Initialize any miscellaneous operating system settings that need to be
2218 // set for the class libraries. Currently this is no-op everywhere except
2219 // for Windows where the process-wide error mode is set before the java.io
2220 // classes are used.
2221 VM.initializeOSEnvironment();
2222
2223 // start Finalizer and Reference Handler threads
2224 SharedSecrets.getJavaLangRefAccess().startThreads();
2225
2226 // system properties, java.lang and other core classes are now initialized
2227 VM.initLevel(1);
2228 }
2229
2230 /**
2231 * System.in.
2232 */
2233 private static class In extends FileInputStream {
2234 In(FileDescriptor fd) {
2235 super(fd);
2236 }
2237
2238 @Override
2239 public int read() throws IOException {
2240 boolean attempted = Blocker.begin();
2241 try {
2242 return super.read();
2243 } finally {
2244 Blocker.end(attempted);
2245 }
2246 }
2247
2248 @Override
2249 public int read(byte[] b) throws IOException {
2250 boolean attempted = Blocker.begin();
2251 try {
2252 return super.read(b);
2253 } finally {
2254 Blocker.end(attempted);
2255 }
2256 }
2257
2258 @Override
2259 public int read(byte[] b, int off, int len) throws IOException {
2260 boolean attempted = Blocker.begin();
2261 try {
2262 return super.read(b, off, len);
2263 } finally {
2264 Blocker.end(attempted);
2265 }
2266 }
2267 }
2268
2269 /**
2270 * System.out/System.err wrap this output stream.
2271 */
2272 private static class Out extends FileOutputStream {
2273 Out(FileDescriptor fd) {
2274 super(fd);
2275 }
2276
2277 @Override
2278 public void write(int b) throws IOException {
2279 boolean attempted = Blocker.begin();
2280 try {
2281 super.write(b);
2282 } finally {
2283 Blocker.end(attempted);
2284 }
2285 }
2286
2287 @Override
2288 public void write(byte[] b) throws IOException {
2289 boolean attempted = Blocker.begin();
2290 try {
2291 super.write(b);
2292 } finally {
2293 Blocker.end(attempted);
2294 }
2295 }
2296
2297 @Override
2298 public void write(byte[] b, int off, int len) throws IOException {
2299 boolean attempted = Blocker.begin();
2300 try {
2301 super.write(b, off, len);
2302 } finally {
2303 Blocker.end(attempted);
2304 }
2305 }
2306 }
2307
2308 // @see #initPhase2()
2309 static ModuleLayer bootLayer;
2310
2311 /*
2312 * Invoked by VM. Phase 2 module system initialization.
2313 * Only classes in java.base can be loaded in this phase.
2314 *
2315 * @param printToStderr print exceptions to stderr rather than stdout
2316 * @param printStackTrace print stack trace when exception occurs
2317 *
2318 * @return JNI_OK for success, JNI_ERR for failure
2319 */
2320 private static int initPhase2(boolean printToStderr, boolean printStackTrace) {
2321
2322 try {
2323 bootLayer = ModuleBootstrap.boot();
2324 } catch (Exception | Error e) {
2325 logInitException(printToStderr, printStackTrace,
2326 "Error occurred during initialization of boot layer", e);
2327 return -1; // JNI_ERR
2328 }
2329
2330 // module system initialized
2331 VM.initLevel(2);
2332
2333 return 0; // JNI_OK
2334 }
2335
2336 /*
2337 * Invoked by VM. Phase 3 is the final system initialization:
2338 * 1. eagerly initialize bootstrap method factories that might interact
2339 * negatively with custom security managers and custom class loaders
2340 * 2. set security manager
2341 * 3. set system class loader
2342 * 4. set TCCL
2343 *
2344 * This method must be called after the module system initialization.
2345 * The security manager and system class loader may be a custom class from
2346 * the application classpath or modulepath.
2347 */
2348 @SuppressWarnings("removal")
2349 private static void initPhase3() {
2350
2351 // Initialize the StringConcatFactory eagerly to avoid potential
2352 // bootstrap circularity issues that could be caused by a custom
2353 // SecurityManager
2354 Unsafe.getUnsafe().ensureClassInitialized(StringConcatFactory.class);
2355
2356 // Emit a warning if java.io.tmpdir is set via the command line
2357 // to a directory that doesn't exist
2358 if (SystemProps.isBadIoTmpdir()) {
2359 System.err.println("WARNING: java.io.tmpdir directory does not exist");
2360 }
2361
2362 String smProp = System.getProperty("java.security.manager");
2363 boolean needWarning = false;
2364 if (smProp != null) {
2365 switch (smProp) {
2366 case "disallow":
2367 allowSecurityManager = NEVER;
2368 break;
2369 case "allow":
2370 allowSecurityManager = MAYBE;
2371 break;
2372 case "":
2373 case "default":
2374 implSetSecurityManager(new SecurityManager());
2375 allowSecurityManager = MAYBE;
2376 needWarning = true;
2377 break;
2378 default:
2379 try {
2380 ClassLoader cl = ClassLoader.getBuiltinAppClassLoader();
2381 Class<?> c = Class.forName(smProp, false, cl);
2382 Constructor<?> ctor = c.getConstructor();
2383 // Must be a public subclass of SecurityManager with
2384 // a public no-arg constructor
2385 if (!SecurityManager.class.isAssignableFrom(c) ||
2386 !Modifier.isPublic(c.getModifiers()) ||
2387 !Modifier.isPublic(ctor.getModifiers())) {
2388 throw new Error("Could not create SecurityManager: "
2389 + ctor.toString());
2390 }
2391 // custom security manager may be in non-exported package
2392 ctor.setAccessible(true);
2393 SecurityManager sm = (SecurityManager) ctor.newInstance();
2394 implSetSecurityManager(sm);
2395 needWarning = true;
2396 } catch (Exception e) {
2397 throw new InternalError("Could not create SecurityManager", e);
2398 }
2399 allowSecurityManager = MAYBE;
2400 }
2401 } else {
2402 allowSecurityManager = NEVER;
2403 }
2404
2405 if (needWarning) {
2406 System.err.println("""
2407 WARNING: A command line option has enabled the Security Manager
2408 WARNING: The Security Manager is deprecated and will be removed in a future release""");
2409 }
2410
2411 // Emit a warning if `sun.jnu.encoding` is not supported.
2412 if (notSupportedJnuEncoding != null) {
2413 System.err.println(
2414 "WARNING: The encoding of the underlying platform's" +
2415 " file system is not supported: " +
2416 notSupportedJnuEncoding);
2417 }
2418
2419 // initializing the system class loader
2420 VM.initLevel(3);
2421
2422 // system class loader initialized
2423 ClassLoader scl = ClassLoader.initSystemClassLoader();
2424
2425 // set TCCL
2426 Thread.currentThread().setContextClassLoader(scl);
2427
2428 // system is fully initialized
2429 VM.initLevel(4);
2430 }
2431
2432 private static void setJavaLangAccess() {
2433 // Allow privileged classes outside of java.lang
2434 SharedSecrets.setJavaLangAccess(new JavaLangAccess() {
2435 public List<Method> getDeclaredPublicMethods(Class<?> klass, String name, Class<?>... parameterTypes) {
2436 return klass.getDeclaredPublicMethods(name, parameterTypes);
2437 }
2438 public Method findMethod(Class<?> klass, boolean publicOnly, String name, Class<?>... parameterTypes) {
2439 return klass.findMethod(publicOnly, name, parameterTypes);
2440 }
2441 public jdk.internal.reflect.ConstantPool getConstantPool(Class<?> klass) {
2442 return klass.getConstantPool();
2443 }
2444 public boolean casAnnotationType(Class<?> klass, AnnotationType oldType, AnnotationType newType) {
2445 return klass.casAnnotationType(oldType, newType);
2446 }
2447 public AnnotationType getAnnotationType(Class<?> klass) {
2448 return klass.getAnnotationType();
2449 }
2450 public Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap(Class<?> klass) {
2451 return klass.getDeclaredAnnotationMap();
2452 }
2453 public byte[] getRawClassAnnotations(Class<?> klass) {
2454 return klass.getRawAnnotations();
2455 }
2456 public byte[] getRawClassTypeAnnotations(Class<?> klass) {
2457 return klass.getRawTypeAnnotations();
2458 }
2459 public byte[] getRawExecutableTypeAnnotations(Executable executable) {
2460 return Class.getExecutableTypeAnnotationBytes(executable);
2461 }
2462 public <E extends Enum<E>>
2463 E[] getEnumConstantsShared(Class<E> klass) {
2464 return klass.getEnumConstantsShared();
2465 }
2466 public void blockedOn(Interruptible b) {
2467 Thread.currentThread().blockedOn(b);
2468 }
2469 public void registerShutdownHook(int slot, boolean registerShutdownInProgress, Runnable hook) {
2470 Shutdown.add(slot, registerShutdownInProgress, hook);
2471 }
2472 public Thread newThreadWithAcc(Runnable target, @SuppressWarnings("removal") AccessControlContext acc) {
2473 return new Thread(target, acc);
2474 }
2475 @SuppressWarnings("removal")
2476 public void invokeFinalize(Object o) throws Throwable {
2477 o.finalize();
2478 }
2479 public ConcurrentHashMap<?, ?> createOrGetClassLoaderValueMap(ClassLoader cl) {
2480 return cl.createOrGetClassLoaderValueMap();
2481 }
2482 public Class<?> defineClass(ClassLoader loader, String name, byte[] b, ProtectionDomain pd, String source) {
2483 return ClassLoader.defineClass1(loader, name, b, 0, b.length, pd, source);
2484 }
2485 public Class<?> defineClass(ClassLoader loader, Class<?> lookup, String name, byte[] b, ProtectionDomain pd,
2486 boolean initialize, int flags, Object classData) {
2487 return ClassLoader.defineClass0(loader, lookup, name, b, 0, b.length, pd, initialize, flags, classData);
2488 }
2489 public Class<?> findBootstrapClassOrNull(String name) {
2490 return ClassLoader.findBootstrapClassOrNull(name);
2491 }
2492 public Package definePackage(ClassLoader cl, String name, Module module) {
2493 return cl.definePackage(name, module);
2494 }
2495 @SuppressWarnings("removal")
2496 public void addNonExportedPackages(ModuleLayer layer) {
2497 SecurityManager.addNonExportedPackages(layer);
2498 }
2499 @SuppressWarnings("removal")
2500 public void invalidatePackageAccessCache() {
2501 SecurityManager.invalidatePackageAccessCache();
2502 }
2503 public Module defineModule(ClassLoader loader,
2504 ModuleDescriptor descriptor,
2505 URI uri) {
2506 return new Module(null, loader, descriptor, uri);
2507 }
2508 public Module defineUnnamedModule(ClassLoader loader) {
2509 return new Module(loader);
2510 }
2511 public void addReads(Module m1, Module m2) {
2512 m1.implAddReads(m2);
2513 }
2514 public void addReadsAllUnnamed(Module m) {
2515 m.implAddReadsAllUnnamed();
2516 }
2517 public void addExports(Module m, String pn) {
2518 m.implAddExports(pn);
2519 }
2520 public void addExports(Module m, String pn, Module other) {
2521 m.implAddExports(pn, other);
2522 }
2523 public void addExportsToAllUnnamed(Module m, String pn) {
2524 m.implAddExportsToAllUnnamed(pn);
2525 }
2526 public void addOpens(Module m, String pn, Module other) {
2527 m.implAddOpens(pn, other);
2528 }
2529 public void addOpensToAllUnnamed(Module m, String pn) {
2530 m.implAddOpensToAllUnnamed(pn);
2531 }
2532 public void addOpensToAllUnnamed(Module m, Set<String> concealedPackages, Set<String> exportedPackages) {
2533 m.implAddOpensToAllUnnamed(concealedPackages, exportedPackages);
2534 }
2535 public void addUses(Module m, Class<?> service) {
2536 m.implAddUses(service);
2537 }
2538 public boolean isReflectivelyExported(Module m, String pn, Module other) {
2539 return m.isReflectivelyExported(pn, other);
2540 }
2541 public boolean isReflectivelyOpened(Module m, String pn, Module other) {
2542 return m.isReflectivelyOpened(pn, other);
2543 }
2544 public Module addEnableNativeAccess(Module m) {
2545 return m.implAddEnableNativeAccess();
2546 }
2547 public boolean addEnableNativeAccess(ModuleLayer layer, String name) {
2548 return layer.addEnableNativeAccess(name);
2549 }
2550 public void addEnableNativeAccessToAllUnnamed() {
2551 Module.implAddEnableNativeAccessToAllUnnamed();
2552 }
2553 public void ensureNativeAccess(Module m, Class<?> owner, String methodName, Class<?> currentClass, boolean jni) {
2554 m.ensureNativeAccess(owner, methodName, currentClass, jni);
2555 }
2556 public ServicesCatalog getServicesCatalog(ModuleLayer layer) {
2557 return layer.getServicesCatalog();
2558 }
2559 public void bindToLoader(ModuleLayer layer, ClassLoader loader) {
2560 layer.bindToLoader(loader);
2561 }
2562 public Stream<ModuleLayer> layers(ModuleLayer layer) {
2563 return layer.layers();
2564 }
2565 public Stream<ModuleLayer> layers(ClassLoader loader) {
2566 return ModuleLayer.layers(loader);
2567 }
2568
2569 public int countPositives(byte[] bytes, int offset, int length) {
2570 return StringCoding.countPositives(bytes, offset, length);
2571 }
2572 public String newStringNoRepl(byte[] bytes, Charset cs) throws CharacterCodingException {
2573 return String.newStringNoRepl(bytes, cs);
2574 }
2575 public char getUTF16Char(byte[] bytes, int index) {
2576 return StringUTF16.getChar(bytes, index);
2577 }
2578 public void putCharUTF16(byte[] bytes, int index, int ch) {
2579 StringUTF16.putChar(bytes, index, ch);
2580 }
2581 public byte[] getBytesNoRepl(String s, Charset cs) throws CharacterCodingException {
2582 return String.getBytesNoRepl(s, cs);
2583 }
2584
2585 public String newStringUTF8NoRepl(byte[] bytes, int off, int len) {
2586 return String.newStringUTF8NoRepl(bytes, off, len, true);
2587 }
2588
2589 public byte[] getBytesUTF8NoRepl(String s) {
2590 return String.getBytesUTF8NoRepl(s);
2591 }
2592
2593 public void inflateBytesToChars(byte[] src, int srcOff, char[] dst, int dstOff, int len) {
2594 StringLatin1.inflate(src, srcOff, dst, dstOff, len);
2595 }
2596
2597 public int decodeASCII(byte[] src, int srcOff, char[] dst, int dstOff, int len) {
2598 return String.decodeASCII(src, srcOff, dst, dstOff, len);
2599 }
2600
2601 public int encodeASCII(char[] src, int srcOff, byte[] dst, int dstOff, int len) {
2602 return StringCoding.implEncodeAsciiArray(src, srcOff, dst, dstOff, len);
2603 }
2604
2605 public InputStream initialSystemIn() {
2606 return initialIn;
2607 }
2608
2609 public PrintStream initialSystemErr() {
2610 return initialErr;
2611 }
2612
2613 public void setCause(Throwable t, Throwable cause) {
2614 t.setCause(cause);
2615 }
2616
2617 public ProtectionDomain protectionDomain(Class<?> c) {
2618 return c.protectionDomain();
2619 }
2620
2621 public MethodHandle stringConcatHelper(String name, MethodType methodType) {
2622 return StringConcatHelper.lookupStatic(name, methodType);
2623 }
2624
2625 public long stringConcatInitialCoder() {
2626 return StringConcatHelper.initialCoder();
2627 }
2628
2629 public long stringConcatMix(long lengthCoder, String constant) {
2630 return StringConcatHelper.mix(lengthCoder, constant);
2631 }
2632
2633 public long stringConcatMix(long lengthCoder, char value) {
2634 return StringConcatHelper.mix(lengthCoder, value);
2635 }
2636
2637 public Object stringConcat1(String[] constants) {
2638 return new StringConcatHelper.Concat1(constants);
2639 }
2640
2641 public int getCharsLatin1(long i, int index, byte[] buf) {
2642 return StringLatin1.getChars(i, index, buf);
2643 }
2644
2645 public int getCharsUTF16(long i, int index, byte[] buf) {
2646 return StringUTF16.getChars(i, index, buf);
2647 }
2648
2649 public String join(String prefix, String suffix, String delimiter, String[] elements, int size) {
2650 return String.join(prefix, suffix, delimiter, elements, size);
2651 }
2652
2653 public String concat(String prefix, Object value, String suffix) {
2654 return StringConcatHelper.concat(prefix, value, suffix);
2655 }
2656
2657 public Object classData(Class<?> c) {
2658 return c.getClassData();
2659 }
2660
2661 @Override
2662 public long findNative(ClassLoader loader, String entry) {
2663 return ClassLoader.findNativeInternal(loader, entry);
2664 }
2665
2666 @Override
2667 public void exit(int statusCode) {
2668 Shutdown.exit(statusCode);
2669 }
2670
2671 public Thread[] getAllThreads() {
2672 return Thread.getAllThreads();
2673 }
2674
2675 public ThreadContainer threadContainer(Thread thread) {
2676 return thread.threadContainer();
2677 }
2678
2679 public void start(Thread thread, ThreadContainer container) {
2680 thread.start(container);
2681 }
2682
2683 public StackableScope headStackableScope(Thread thread) {
2684 return thread.headStackableScopes();
2685 }
2686
2687 public void setHeadStackableScope(StackableScope scope) {
2688 Thread.setHeadStackableScope(scope);
2689 }
2690
2691 public Thread currentCarrierThread() {
2692 return Thread.currentCarrierThread();
2693 }
2694
2695 public <T> T getCarrierThreadLocal(CarrierThreadLocal<T> local) {
2696 return ((ThreadLocal<T>)local).getCarrierThreadLocal();
2697 }
2698
2699 public <T> void setCarrierThreadLocal(CarrierThreadLocal<T> local, T value) {
2700 ((ThreadLocal<T>)local).setCarrierThreadLocal(value);
2701 }
2702
2703 public void removeCarrierThreadLocal(CarrierThreadLocal<?> local) {
2704 ((ThreadLocal<?>)local).removeCarrierThreadLocal();
2705 }
2706
2707 public boolean isCarrierThreadLocalPresent(CarrierThreadLocal<?> local) {
2708 return ((ThreadLocal<?>)local).isCarrierThreadLocalPresent();
2709 }
2710
2711 public Object[] scopedValueCache() {
2712 return Thread.scopedValueCache();
2713 }
2714
2715 public void setScopedValueCache(Object[] cache) {
2716 Thread.setScopedValueCache(cache);
2717 }
2718
2719 public Object scopedValueBindings() {
2720 return Thread.scopedValueBindings();
2721 }
2722
2723 public Continuation getContinuation(Thread thread) {
2724 return thread.getContinuation();
2725 }
2726
2727 public void setContinuation(Thread thread, Continuation continuation) {
2728 thread.setContinuation(continuation);
2729 }
2730
2731 public ContinuationScope virtualThreadContinuationScope() {
2732 return VirtualThread.continuationScope();
2733 }
2734
2735 public void parkVirtualThread() {
2736 Thread thread = Thread.currentThread();
2737 if (thread instanceof BaseVirtualThread vthread) {
2738 vthread.park();
2739 } else {
2740 throw new WrongThreadException();
2741 }
2742 }
2743
2744 public void parkVirtualThread(long nanos) {
2745 Thread thread = Thread.currentThread();
2746 if (thread instanceof BaseVirtualThread vthread) {
2747 vthread.parkNanos(nanos);
2748 } else {
2749 throw new WrongThreadException();
2750 }
2751 }
2752
2753 public void unparkVirtualThread(Thread thread) {
2754 if (thread instanceof BaseVirtualThread vthread) {
2755 vthread.unpark();
2756 } else {
2757 throw new WrongThreadException();
2758 }
2759 }
2760
2761 public StackWalker newStackWalkerInstance(Set<StackWalker.Option> options,
2762 ContinuationScope contScope,
2763 Continuation continuation) {
2764 return StackWalker.newInstance(options, null, contScope, continuation);
2765 }
2766
2767 public String getLoaderNameID(ClassLoader loader) {
2768 return loader != null ? loader.nameAndId() : "null";
2769 }
2770
2771 @Override
2772 public void copyToSegmentRaw(String string, MemorySegment segment, long offset) {
2773 string.copyToSegmentRaw(segment, offset);
2774 }
2775
2776 @Override
2777 public boolean bytesCompatible(String string, Charset charset) {
2778 return string.bytesCompatible(charset);
2779 }
2780
2781 @Override
2782 public boolean allowSecurityManager() {
2783 return System.allowSecurityManager();
2784 }
2785 });
2786 }
2787 }