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/**
* Class {@code Object} is the root of the class hierarchy.
* Every class has {@code Object} as a superclass. All objects,
* including arrays, implement the methods of this class.
*
+ * <div class="preview-block">
+ * <div class="preview-comment">
+ * When preview features are enabled, subclasses of {@code java.lang.Object} can be either
+ * an {@linkplain Class#isIdentity identity class} or a {@linkplain Class#isValue value class}.
+ * See {@jls The Java Language Specification 8.1.1.5 Value Classes}.
+ * Use of value class instances for synchronization, mutexes, or with
+ * {@linkplain java.lang.ref.Reference object references} result in
+ * {@link IdentityException}.
+ * </div>
+ * </div>
+ *
* @see java.lang.Class
* @since 1.0
*/
public class Object {
* <li>For objects of type {@code Class,} by executing a
* static synchronized method of that class.
* </ul>
* <p>
* Only one thread at a time can own an object's monitor.
+ * <div class="preview-block">
+ * <div class="preview-comment">
+ * If this object is a {@linkplain Class#isValue() value object},
+ * it does does not have a monitor, an {@code IllegalMonitorStateException} is thrown.
+ * </div>
+ * </div>
*
* @throws IllegalMonitorStateException if the current thread is not
- * the owner of this object's monitor.
+ * the owner of this object's monitor or
+ * if this object is a {@linkplain Class#isValue() value object}.
* @see java.lang.Object#notifyAll()
* @see java.lang.Object#wait()
*/
@IntrinsicCandidate
public final native void notify();
* This method should only be called by a thread that is the owner
* of this object's monitor. See the {@code notify} method for a
* description of the ways in which a thread can become the owner of
* a monitor.
*
+ * <div class="preview-block">
+ * <div class="preview-comment">
+ * If this object is a {@linkplain Class#isValue() value object},
+ * it does does not have a monitor, an {@code IllegalMonitorStateException} is thrown.
+ * </div>
+ * </div>
+ *
* @throws IllegalMonitorStateException if the current thread is not
- * the owner of this object's monitor.
+ * the owner of this object's monitor or
+ * if this object is a {@linkplain Class#isValue() value object}.
* @see java.lang.Object#notify()
* @see java.lang.Object#wait()
*/
@IntrinsicCandidate
public final native void notifyAll();
* <p>
* In all respects, this method behaves as if {@code wait(0L, 0)}
* had been called. See the specification of the {@link #wait(long, int)} method
* for details.
*
+ * <div class="preview-block">
+ * <div class="preview-comment">
+ * If this object is a {@linkplain Class#isValue() value object},
+ * it does does not have a monitor, an {@code IllegalMonitorStateException} is thrown.
+ * </div>
+ * </div>
+ *
* @throws IllegalMonitorStateException if the current thread is not
- * the owner of the object's monitor
+ * the owner of the object's monitor or
+ * if this object is a {@linkplain Class#isValue() value object}.
* @throws InterruptedException if any thread interrupted the current thread before or
* while the current thread was waiting. The <em>interrupted status</em> of the
* current thread is cleared when this exception is thrown.
* @see #notify()
* @see #notifyAll()
* <p>
* In all respects, this method behaves as if {@code wait(timeoutMillis, 0)}
* had been called. See the specification of the {@link #wait(long, int)} method
* for details.
*
+ * <div class="preview-block">
+ * <div class="preview-comment">
+ * If this object is a {@linkplain Class#isValue() value object},
+ * it does does not have a monitor, an {@code IllegalMonitorStateException} is thrown.
+ * </div>
+ * </div>
+ *
* @param timeoutMillis the maximum time to wait, in milliseconds
* @throws IllegalArgumentException if {@code timeoutMillis} is negative
* @throws IllegalMonitorStateException if the current thread is not
- * the owner of the object's monitor
+ * the owner of the object's monitor or
+ * if this object is a {@linkplain Class#isValue() value object}.
* @throws InterruptedException if any thread interrupted the current thread before or
* while the current thread was waiting. The <em>interrupted status</em> of the
* current thread is cleared when this exception is thrown.
* @see #notify()
* @see #notifyAll()
* }
* ... // Perform action appropriate to condition or timeout
* }
* }
*
+ * <div class="preview-block">
+ * <div class="preview-comment">
+ * If this object is a {@linkplain Class#isValue() value object},
+ * it does does not have a monitor, an {@code IllegalMonitorStateException} is thrown.
+ * </div>
+ * </div>
* @param timeoutMillis the maximum time to wait, in milliseconds
* @param nanos additional time, in nanoseconds, in the range 0-999999 inclusive
* @throws IllegalArgumentException if {@code timeoutMillis} is negative,
* or if the value of {@code nanos} is out of range
* @throws IllegalMonitorStateException if the current thread is not
- * the owner of the object's monitor
+ * the owner of the object's monitor or
+ * if this object is a {@linkplain Class#isValue() value object}.
* @throws InterruptedException if any thread interrupted the current thread before or
* while the current thread was waiting. The <em>interrupted status</em> of the
* current thread is cleared when this exception is thrown.
* @see #notify()
* @see #notifyAll()
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