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