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