src/share/classes/java/lang/Object.java
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rev 814 : 6239194: Object.hashCode() should reference System.identityHashCode()
Reviewed-by: emcmanus
*** 24,35 ****
*/
package java.lang;
/**
! * Class <code>Object</code> is the root of the class hierarchy.
! * Every class has <code>Object</code> as a superclass. All objects,
* including arrays, implement the methods of this class.
*
* @author unascribed
* @see java.lang.Class
* @since JDK1.0
--- 24,35 ----
*/
package java.lang;
/**
! * 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.
*
* @author unascribed
* @see java.lang.Class
* @since JDK1.0
*** 64,229 ****
*/
public final native Class<?> getClass();
/**
* Returns a hash code value for the object. This method is
! * supported for the benefit of hashtables such as those provided by
! * <code>java.util.Hashtable</code>.
* <p>
! * The general contract of <code>hashCode</code> is:
* <ul>
* <li>Whenever it is invoked on the same object more than once during
! * an execution of a Java application, the <tt>hashCode</tt> method
* must consistently return the same integer, provided no information
! * used in <tt>equals</tt> comparisons on the object is modified.
* This integer need not remain consistent from one execution of an
* application to another execution of the same application.
! * <li>If two objects are equal according to the <tt>equals(Object)</tt>
! * method, then calling the <code>hashCode</code> method on each of
* the two objects must produce the same integer result.
* <li>It is <em>not</em> required that if two objects are unequal
* according to the {@link java.lang.Object#equals(java.lang.Object)}
! * method, then calling the <tt>hashCode</tt> method on each of the
* two objects must produce distinct integer results. However, the
* programmer should be aware that producing distinct integer results
! * for unequal objects may improve the performance of hashtables.
* </ul>
* <p>
* As much as is reasonably practical, the hashCode method defined by
! * class <tt>Object</tt> does return distinct integers for distinct
* objects. (This is typically implemented by converting the internal
* address of the object into an integer, but this implementation
* technique is not required by the
* Java<font size="-2"><sup>TM</sup></font> programming language.)
*
* @return a hash code value for this object.
* @see java.lang.Object#equals(java.lang.Object)
! * @see java.util.Hashtable
*/
public native int hashCode();
/**
* Indicates whether some other object is "equal to" this one.
* <p>
! * The <code>equals</code> method implements an equivalence relation
* on non-null object references:
* <ul>
* <li>It is <i>reflexive</i>: for any non-null reference value
! * <code>x</code>, <code>x.equals(x)</code> should return
! * <code>true</code>.
* <li>It is <i>symmetric</i>: for any non-null reference values
! * <code>x</code> and <code>y</code>, <code>x.equals(y)</code>
! * should return <code>true</code> if and only if
! * <code>y.equals(x)</code> returns <code>true</code>.
* <li>It is <i>transitive</i>: for any non-null reference values
! * <code>x</code>, <code>y</code>, and <code>z</code>, if
! * <code>x.equals(y)</code> returns <code>true</code> and
! * <code>y.equals(z)</code> returns <code>true</code>, then
! * <code>x.equals(z)</code> should return <code>true</code>.
* <li>It is <i>consistent</i>: for any non-null reference values
! * <code>x</code> and <code>y</code>, multiple invocations of
! * <tt>x.equals(y)</tt> consistently return <code>true</code>
! * or consistently return <code>false</code>, provided no
! * information used in <code>equals</code> comparisons on the
* objects is modified.
! * <li>For any non-null reference value <code>x</code>,
! * <code>x.equals(null)</code> should return <code>false</code>.
* </ul>
* <p>
! * The <tt>equals</tt> method for class <code>Object</code> implements
* the most discriminating possible equivalence relation on objects;
! * that is, for any non-null reference values <code>x</code> and
! * <code>y</code>, this method returns <code>true</code> if and only
! * if <code>x</code> and <code>y</code> refer to the same object
! * (<code>x == y</code> has the value <code>true</code>).
* <p>
! * Note that it is generally necessary to override the <tt>hashCode</tt>
* method whenever this method is overridden, so as to maintain the
! * general contract for the <tt>hashCode</tt> method, which states
* that equal objects must have equal hash codes.
*
* @param obj the reference object with which to compare.
! * @return <code>true</code> if this object is the same as the obj
! * argument; <code>false</code> otherwise.
* @see #hashCode()
! * @see java.util.Hashtable
*/
public boolean equals(Object obj) {
return (this == obj);
}
/**
* Creates and returns a copy of this object. The precise meaning
* of "copy" may depend on the class of the object. The general
! * intent is that, for any object <tt>x</tt>, the expression:
* <blockquote>
* <pre>
* x.clone() != x</pre></blockquote>
* will be true, and that the expression:
* <blockquote>
* <pre>
* x.clone().getClass() == x.getClass()</pre></blockquote>
! * will be <tt>true</tt>, but these are not absolute requirements.
* While it is typically the case that:
* <blockquote>
* <pre>
* x.clone().equals(x)</pre></blockquote>
! * will be <tt>true</tt>, this is not an absolute requirement.
* <p>
* By convention, the returned object should be obtained by calling
! * <tt>super.clone</tt>. If a class and all of its superclasses (except
! * <tt>Object</tt>) obey this convention, it will be the case that
! * <tt>x.clone().getClass() == x.getClass()</tt>.
* <p>
* By convention, the object returned by this method should be independent
* of this object (which is being cloned). To achieve this independence,
* it may be necessary to modify one or more fields of the object returned
! * by <tt>super.clone</tt> before returning it. Typically, this means
* copying any mutable objects that comprise the internal "deep structure"
* of the object being cloned and replacing the references to these
* objects with references to the copies. If a class contains only
* primitive fields or references to immutable objects, then it is usually
! * the case that no fields in the object returned by <tt>super.clone</tt>
* need to be modified.
* <p>
! * The method <tt>clone</tt> for class <tt>Object</tt> performs a
* specific cloning operation. First, if the class of this object does
! * not implement the interface <tt>Cloneable</tt>, then a
! * <tt>CloneNotSupportedException</tt> is thrown. Note that all arrays
! * are considered to implement the interface <tt>Cloneable</tt>.
* Otherwise, this method creates a new instance of the class of this
* object and initializes all its fields with exactly the contents of
* the corresponding fields of this object, as if by assignment; the
* contents of the fields are not themselves cloned. Thus, this method
* performs a "shallow copy" of this object, not a "deep copy" operation.
* <p>
! * The class <tt>Object</tt> does not itself implement the interface
! * <tt>Cloneable</tt>, so calling the <tt>clone</tt> method on an object
! * whose class is <tt>Object</tt> will result in throwing an
* exception at run time.
*
* @return a clone of this instance.
* @exception CloneNotSupportedException if the object's class does not
! * support the <code>Cloneable</code> interface. Subclasses
! * that override the <code>clone</code> method can also
* throw this exception to indicate that an instance cannot
* be cloned.
* @see java.lang.Cloneable
*/
protected native Object clone() throws CloneNotSupportedException;
/**
* Returns a string representation of the object. In general, the
! * <code>toString</code> method returns a string that
* "textually represents" this object. The result should
* be a concise but informative representation that is easy for a
* person to read.
* It is recommended that all subclasses override this method.
* <p>
! * The <code>toString</code> method for class <code>Object</code>
* returns a string consisting of the name of the class of which the
! * object is an instance, the at-sign character `<code>@</code>', and
* the unsigned hexadecimal representation of the hash code of the
* object. In other words, this method returns a string equal to the
* value of:
* <blockquote>
* <pre>
--- 64,229 ----
*/
public final native Class<?> getClass();
/**
* Returns a hash code value for the object. This method is
! * supported for the benefit of hash tables such as those provided by
! * {@link java.util.HashMap}.
* <p>
! * The general contract of {@code hashCode} is:
* <ul>
* <li>Whenever it is invoked on the same object more than once during
! * an execution of a Java application, the {@code hashCode} method
* must consistently return the same integer, provided no information
! * used in {@code equals} comparisons on the object is modified.
* This integer need not remain consistent from one execution of an
* application to another execution of the same application.
! * <li>If two objects are equal according to the {@code equals(Object)}
! * method, then calling the {@code hashCode} method on each of
* the two objects must produce the same integer result.
* <li>It is <em>not</em> required that if two objects are unequal
* according to the {@link java.lang.Object#equals(java.lang.Object)}
! * method, then calling the {@code hashCode} method on each of the
* two objects must produce distinct integer results. However, the
* programmer should be aware that producing distinct integer results
! * for unequal objects may improve the performance of hash tables.
* </ul>
* <p>
* As much as is reasonably practical, the hashCode method defined by
! * class {@code Object} does return distinct integers for distinct
* objects. (This is typically implemented by converting the internal
* address of the object into an integer, but this implementation
* technique is not required by the
* Java<font size="-2"><sup>TM</sup></font> programming language.)
*
* @return a hash code value for this object.
* @see java.lang.Object#equals(java.lang.Object)
! * @see java.lang.System#identityHashCode
*/
public native int hashCode();
/**
* Indicates whether some other object is "equal to" this one.
* <p>
! * The {@code equals} method implements an equivalence relation
* on non-null object references:
* <ul>
* <li>It is <i>reflexive</i>: for any non-null reference value
! * {@code x}, {@code x.equals(x)} should return
! * {@code true}.
* <li>It is <i>symmetric</i>: for any non-null reference values
! * {@code x} and {@code y}, {@code x.equals(y)}
! * should return {@code true} if and only if
! * {@code y.equals(x)} returns {@code true}.
* <li>It is <i>transitive</i>: for any non-null reference values
! * {@code x}, {@code y}, and {@code z}, if
! * {@code x.equals(y)} returns {@code true} and
! * {@code y.equals(z)} returns {@code true}, then
! * {@code x.equals(z)} should return {@code true}.
* <li>It is <i>consistent</i>: for any non-null reference values
! * {@code x} and {@code y}, multiple invocations of
! * {@code x.equals(y)} consistently return {@code true}
! * or consistently return {@code false}, provided no
! * information used in {@code equals} comparisons on the
* objects is modified.
! * <li>For any non-null reference value {@code x},
! * {@code x.equals(null)} should return {@code false}.
* </ul>
* <p>
! * The {@code equals} method for class {@code Object} implements
* the most discriminating possible equivalence relation on objects;
! * that is, for any non-null reference values {@code x} and
! * {@code y}, this method returns {@code true} if and only
! * if {@code x} and {@code y} refer to the same object
! * ({@code x == y} has the value {@code true}).
* <p>
! * Note that it is generally necessary to override the {@code hashCode}
* method whenever this method is overridden, so as to maintain the
! * general contract for the {@code hashCode} method, which states
* that equal objects must have equal hash codes.
*
* @param obj the reference object with which to compare.
! * @return {@code true} if this object is the same as the obj
! * argument; {@code false} otherwise.
* @see #hashCode()
! * @see java.util.HashMap
*/
public boolean equals(Object obj) {
return (this == obj);
}
/**
* Creates and returns a copy of this object. The precise meaning
* of "copy" may depend on the class of the object. The general
! * intent is that, for any object {@code x}, the expression:
* <blockquote>
* <pre>
* x.clone() != x</pre></blockquote>
* will be true, and that the expression:
* <blockquote>
* <pre>
* x.clone().getClass() == x.getClass()</pre></blockquote>
! * will be {@code true}, but these are not absolute requirements.
* While it is typically the case that:
* <blockquote>
* <pre>
* x.clone().equals(x)</pre></blockquote>
! * will be {@code true}, this is not an absolute requirement.
* <p>
* By convention, the returned object should be obtained by calling
! * {@code super.clone}. If a class and all of its superclasses (except
! * {@code Object}) obey this convention, it will be the case that
! * {@code x.clone().getClass() == x.getClass()}.
* <p>
* By convention, the object returned by this method should be independent
* of this object (which is being cloned). To achieve this independence,
* it may be necessary to modify one or more fields of the object returned
! * by {@code super.clone} before returning it. Typically, this means
* copying any mutable objects that comprise the internal "deep structure"
* of the object being cloned and replacing the references to these
* objects with references to the copies. If a class contains only
* primitive fields or references to immutable objects, then it is usually
! * the case that no fields in the object returned by {@code super.clone}
* need to be modified.
* <p>
! * The method {@code clone} for class {@code Object} performs a
* specific cloning operation. First, if the class of this object does
! * not implement the interface {@code Cloneable}, then a
! * {@code CloneNotSupportedException} is thrown. Note that all arrays
! * are considered to implement the interface {@code Cloneable}.
* Otherwise, this method creates a new instance of the class of this
* object and initializes all its fields with exactly the contents of
* the corresponding fields of this object, as if by assignment; the
* contents of the fields are not themselves cloned. Thus, this method
* performs a "shallow copy" of this object, not a "deep copy" operation.
* <p>
! * The class {@code Object} does not itself implement the interface
! * {@code Cloneable}, so calling the {@code clone} method on an object
! * whose class is {@code Object} will result in throwing an
* exception at run time.
*
* @return a clone of this instance.
* @exception CloneNotSupportedException if the object's class does not
! * support the {@code Cloneable} interface. Subclasses
! * that override the {@code clone} method can also
* throw this exception to indicate that an instance cannot
* be cloned.
* @see java.lang.Cloneable
*/
protected native Object clone() throws CloneNotSupportedException;
/**
* Returns a string representation of the object. In general, the
! * {@code toString} method returns a string that
* "textually represents" this object. The result should
* be a concise but informative representation that is easy for a
* person to read.
* It is recommended that all subclasses override this method.
* <p>
! * The {@code toString} method for class {@code Object}
* returns a string consisting of the name of the class of which the
! * object is an instance, the at-sign character `{@code @}', and
* the unsigned hexadecimal representation of the hash code of the
* object. In other words, this method returns a string equal to the
* value of:
* <blockquote>
* <pre>
*** 239,249 ****
/**
* Wakes up a single thread that is waiting on this object's
* monitor. If any threads are waiting on this object, one of them
* is chosen to be awakened. The choice is arbitrary and occurs at
* the discretion of the implementation. A thread waits on an object's
! * monitor by calling one of the <code>wait</code> methods.
* <p>
* The awakened thread will not be able to proceed until the current
* thread relinquishes the lock on this object. The awakened thread will
* compete in the usual manner with any other threads that might be
* actively competing to synchronize on this object; for example, the
--- 239,249 ----
/**
* Wakes up a single thread that is waiting on this object's
* monitor. If any threads are waiting on this object, one of them
* is chosen to be awakened. The choice is arbitrary and occurs at
* the discretion of the implementation. A thread waits on an object's
! * monitor by calling one of the {@code wait} methods.
* <p>
* The awakened thread will not be able to proceed until the current
* thread relinquishes the lock on this object. The awakened thread will
* compete in the usual manner with any other threads that might be
* actively competing to synchronize on this object; for example, the
*** 253,265 ****
* This method should only be called by a thread that is the owner
* of this object's monitor. A thread becomes the owner of the
* object's monitor in one of three ways:
* <ul>
* <li>By executing a synchronized instance method of that object.
! * <li>By executing the body of a <code>synchronized</code> statement
* that synchronizes on the object.
! * <li>For objects of type <code>Class,</code> by executing a
* synchronized static method of that class.
* </ul>
* <p>
* Only one thread at a time can own an object's monitor.
*
--- 253,265 ----
* This method should only be called by a thread that is the owner
* of this object's monitor. A thread becomes the owner of the
* object's monitor in one of three ways:
* <ul>
* <li>By executing a synchronized instance method of that object.
! * <li>By executing the body of a {@code synchronized} statement
* that synchronizes on the object.
! * <li>For objects of type {@code Class,} by executing a
* synchronized static method of that class.
* </ul>
* <p>
* Only one thread at a time can own an object's monitor.
*
*** 271,291 ****
public final native void notify();
/**
* Wakes up all threads that are waiting on this object's monitor. A
* thread waits on an object's monitor by calling one of the
! * <code>wait</code> methods.
* <p>
* The awakened threads will not be able to proceed until the current
* thread relinquishes the lock on this object. The awakened threads
* will compete in the usual manner with any other threads that might
* be actively competing to synchronize on this object; for example,
* the awakened threads enjoy no reliable privilege or disadvantage in
* being the next thread to lock this object.
* <p>
* This method should only be called by a thread that is the owner
! * of this object's monitor. See the <code>notify</code> method for a
* description of the ways in which a thread can become the owner of
* a monitor.
*
* @exception IllegalMonitorStateException if the current thread is not
* the owner of this object's monitor.
--- 271,291 ----
public final native void notify();
/**
* Wakes up all threads that are waiting on this object's monitor. A
* thread waits on an object's monitor by calling one of the
! * {@code wait} methods.
* <p>
* The awakened threads will not be able to proceed until the current
* thread relinquishes the lock on this object. The awakened threads
* will compete in the usual manner with any other threads that might
* be actively competing to synchronize on this object; for example,
* the awakened threads enjoy no reliable privilege or disadvantage in
* being the next thread to lock this object.
* <p>
* 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.
*
* @exception IllegalMonitorStateException if the current thread is not
* the owner of this object's monitor.
*** 306,336 ****
* place itself in the wait set for this object and then to relinquish
* any and all synchronization claims on this object. Thread <var>T</var>
* becomes disabled for thread scheduling purposes and lies dormant
* until one of four things happens:
* <ul>
! * <li>Some other thread invokes the <tt>notify</tt> method for this
* object and thread <var>T</var> happens to be arbitrarily chosen as
* the thread to be awakened.
! * <li>Some other thread invokes the <tt>notifyAll</tt> method for this
* object.
* <li>Some other thread {@linkplain Thread#interrupt() interrupts}
* thread <var>T</var>.
* <li>The specified amount of real time has elapsed, more or less. If
! * <tt>timeout</tt> is zero, however, then real time is not taken into
* consideration and the thread simply waits until notified.
* </ul>
* The thread <var>T</var> is then removed from the wait set for this
* object and re-enabled for thread scheduling. It then competes in the
* usual manner with other threads for the right to synchronize on the
* object; once it has gained control of the object, all its
* synchronization claims on the object are restored to the status quo
! * ante - that is, to the situation as of the time that the <tt>wait</tt>
* method was invoked. Thread <var>T</var> then returns from the
! * invocation of the <tt>wait</tt> method. Thus, on return from the
! * <tt>wait</tt> method, the synchronization state of the object and of
! * thread <tt>T</tt> is exactly as it was when the <tt>wait</tt> method
* was invoked.
* <p>
* A thread can also wake up without being notified, interrupted, or
* timing out, a so-called <i>spurious wakeup</i>. While this will rarely
* occur in practice, applications must guard against it by testing for
--- 306,336 ----
* place itself in the wait set for this object and then to relinquish
* any and all synchronization claims on this object. Thread <var>T</var>
* becomes disabled for thread scheduling purposes and lies dormant
* until one of four things happens:
* <ul>
! * <li>Some other thread invokes the {@code notify} method for this
* object and thread <var>T</var> happens to be arbitrarily chosen as
* the thread to be awakened.
! * <li>Some other thread invokes the {@code notifyAll} method for this
* object.
* <li>Some other thread {@linkplain Thread#interrupt() interrupts}
* thread <var>T</var>.
* <li>The specified amount of real time has elapsed, more or less. If
! * {@code timeout} is zero, however, then real time is not taken into
* consideration and the thread simply waits until notified.
* </ul>
* The thread <var>T</var> is then removed from the wait set for this
* object and re-enabled for thread scheduling. It then competes in the
* usual manner with other threads for the right to synchronize on the
* object; once it has gained control of the object, all its
* synchronization claims on the object are restored to the status quo
! * ante - that is, to the situation as of the time that the {@code wait}
* method was invoked. Thread <var>T</var> then returns from the
! * invocation of the {@code wait} method. Thus, on return from the
! * {@code wait} method, the synchronization state of the object and of
! * thread {@code T} is exactly as it was when the {@code wait} method
* was invoked.
* <p>
* A thread can also wake up without being notified, interrupted, or
* timing out, a so-called <i>spurious wakeup</i>. While this will rarely
* occur in practice, applications must guard against it by testing for
*** 349,370 ****
* 2000), or Item 50 in Joshua Bloch's "Effective Java Programming
* Language Guide" (Addison-Wesley, 2001).
*
* <p>If the current thread is {@linkplain java.lang.Thread#interrupt()
* interrupted} by any thread before or while it is waiting, then an
! * <tt>InterruptedException</tt> is thrown. This exception is not
* thrown until the lock status of this object has been restored as
* described above.
*
* <p>
! * Note that the <tt>wait</tt> method, as it places the current thread
* into the wait set for this object, unlocks only this object; any
* other objects on which the current thread may be synchronized remain
* locked while the thread waits.
* <p>
* This method should only be called by a thread that is the owner
! * of this object's monitor. See the <code>notify</code> method for a
* description of the ways in which a thread can become the owner of
* a monitor.
*
* @param timeout the maximum time to wait in milliseconds.
* @exception IllegalArgumentException if the value of timeout is
--- 349,370 ----
* 2000), or Item 50 in Joshua Bloch's "Effective Java Programming
* Language Guide" (Addison-Wesley, 2001).
*
* <p>If the current thread is {@linkplain java.lang.Thread#interrupt()
* interrupted} by any thread before or while it is waiting, then an
! * {@code InterruptedException} is thrown. This exception is not
* thrown until the lock status of this object has been restored as
* described above.
*
* <p>
! * Note that the {@code wait} method, as it places the current thread
* into the wait set for this object, unlocks only this object; any
* other objects on which the current thread may be synchronized remain
* locked while the thread waits.
* <p>
* 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.
*
* @param timeout the maximum time to wait in milliseconds.
* @exception IllegalArgumentException if the value of timeout is
*** 386,416 ****
* {@link java.lang.Object#notify()} method or the
* {@link java.lang.Object#notifyAll()} method for this object, or
* some other thread interrupts the current thread, or a certain
* amount of real time has elapsed.
* <p>
! * This method is similar to the <code>wait</code> method of one
* argument, but it allows finer control over the amount of time to
* wait for a notification before giving up. The amount of real time,
* measured in nanoseconds, is given by:
* <blockquote>
* <pre>
* 1000000*timeout+nanos</pre></blockquote>
* <p>
* In all other respects, this method does the same thing as the
* method {@link #wait(long)} of one argument. In particular,
! * <tt>wait(0, 0)</tt> means the same thing as <tt>wait(0)</tt>.
* <p>
* The current thread must own this object's monitor. The thread
* releases ownership of this monitor and waits until either of the
* following two conditions has occurred:
* <ul>
* <li>Another thread notifies threads waiting on this object's monitor
! * to wake up either through a call to the <code>notify</code> method
! * or the <code>notifyAll</code> method.
! * <li>The timeout period, specified by <code>timeout</code>
! * milliseconds plus <code>nanos</code> nanoseconds arguments, has
* elapsed.
* </ul>
* <p>
* The thread then waits until it can re-obtain ownership of the
* monitor and resumes execution.
--- 386,416 ----
* {@link java.lang.Object#notify()} method or the
* {@link java.lang.Object#notifyAll()} method for this object, or
* some other thread interrupts the current thread, or a certain
* amount of real time has elapsed.
* <p>
! * This method is similar to the {@code wait} method of one
* argument, but it allows finer control over the amount of time to
* wait for a notification before giving up. The amount of real time,
* measured in nanoseconds, is given by:
* <blockquote>
* <pre>
* 1000000*timeout+nanos</pre></blockquote>
* <p>
* In all other respects, this method does the same thing as the
* method {@link #wait(long)} of one argument. In particular,
! * {@code wait(0, 0)} means the same thing as {@code wait(0)}.
* <p>
* The current thread must own this object's monitor. The thread
* releases ownership of this monitor and waits until either of the
* following two conditions has occurred:
* <ul>
* <li>Another thread notifies threads waiting on this object's monitor
! * to wake up either through a call to the {@code notify} method
! * or the {@code notifyAll} method.
! * <li>The timeout period, specified by {@code timeout}
! * milliseconds plus {@code nanos} nanoseconds arguments, has
* elapsed.
* </ul>
* <p>
* The thread then waits until it can re-obtain ownership of the
* monitor and resumes execution.
*** 423,433 ****
* obj.wait(timeout, nanos);
* ... // Perform action appropriate to condition
* }
* </pre>
* This method should only be called by a thread that is the owner
! * of this object's monitor. See the <code>notify</code> method for a
* description of the ways in which a thread can become the owner of
* a monitor.
*
* @param timeout the maximum time to wait in milliseconds.
* @param nanos additional time, in nanoseconds range
--- 423,433 ----
* obj.wait(timeout, nanos);
* ... // Perform action appropriate to condition
* }
* </pre>
* 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.
*
* @param timeout the maximum time to wait in milliseconds.
* @param nanos additional time, in nanoseconds range
*** 463,479 ****
/**
* Causes the current thread to wait until another thread invokes the
* {@link java.lang.Object#notify()} method or the
* {@link java.lang.Object#notifyAll()} method for this object.
* In other words, this method behaves exactly as if it simply
! * performs the call <tt>wait(0)</tt>.
* <p>
* The current thread must own this object's monitor. The thread
* releases ownership of this monitor and waits until another thread
* notifies threads waiting on this object's monitor to wake up
! * either through a call to the <code>notify</code> method or the
! * <code>notifyAll</code> method. The thread then waits until it can
* re-obtain ownership of the monitor and resumes execution.
* <p>
* As in the one argument version, interrupts and spurious wakeups are
* possible, and this method should always be used in a loop:
* <pre>
--- 463,479 ----
/**
* Causes the current thread to wait until another thread invokes the
* {@link java.lang.Object#notify()} method or the
* {@link java.lang.Object#notifyAll()} method for this object.
* In other words, this method behaves exactly as if it simply
! * performs the call {@code wait(0)}.
* <p>
* The current thread must own this object's monitor. The thread
* releases ownership of this monitor and waits until another thread
* notifies threads waiting on this object's monitor to wake up
! * either through a call to the {@code notify} method or the
! * {@code notifyAll} method. The thread then waits until it can
* re-obtain ownership of the monitor and resumes execution.
* <p>
* As in the one argument version, interrupts and spurious wakeups are
* possible, and this method should always be used in a loop:
* <pre>
*** 482,492 ****
* obj.wait();
* ... // Perform action appropriate to condition
* }
* </pre>
* This method should only be called by a thread that is the owner
! * of this object's monitor. See the <code>notify</code> method for a
* description of the ways in which a thread can become the owner of
* a monitor.
*
* @exception IllegalMonitorStateException if the current thread is not
* the owner of the object's monitor.
--- 482,492 ----
* obj.wait();
* ... // Perform action appropriate to condition
* }
* </pre>
* 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.
*
* @exception IllegalMonitorStateException if the current thread is not
* the owner of the object's monitor.
*** 503,553 ****
}
/**
* Called by the garbage collector on an object when garbage collection
* determines that there are no more references to the object.
! * A subclass overrides the <code>finalize</code> method to dispose of
* system resources or to perform other cleanup.
* <p>
! * The general contract of <tt>finalize</tt> is that it is invoked
* if and when the Java<font size="-2"><sup>TM</sup></font> virtual
* machine has determined that there is no longer any
* means by which this object can be accessed by any thread that has
* not yet died, except as a result of an action taken by the
* finalization of some other object or class which is ready to be
! * finalized. The <tt>finalize</tt> method may take any action, including
* making this object available again to other threads; the usual purpose
! * of <tt>finalize</tt>, however, is to perform cleanup actions before
* the object is irrevocably discarded. For example, the finalize method
* for an object that represents an input/output connection might perform
* explicit I/O transactions to break the connection before the object is
* permanently discarded.
* <p>
! * The <tt>finalize</tt> method of class <tt>Object</tt> performs no
* special action; it simply returns normally. Subclasses of
! * <tt>Object</tt> may override this definition.
* <p>
* The Java programming language does not guarantee which thread will
! * invoke the <tt>finalize</tt> method for any given object. It is
* guaranteed, however, that the thread that invokes finalize will not
* be holding any user-visible synchronization locks when finalize is
* invoked. If an uncaught exception is thrown by the finalize method,
* the exception is ignored and finalization of that object terminates.
* <p>
! * After the <tt>finalize</tt> method has been invoked for an object, no
* further action is taken until the Java virtual machine has again
* determined that there is no longer any means by which this object can
* be accessed by any thread that has not yet died, including possible
* actions by other objects or classes which are ready to be finalized,
* at which point the object may be discarded.
* <p>
! * The <tt>finalize</tt> method is never invoked more than once by a Java
* virtual machine for any given object.
* <p>
! * Any exception thrown by the <code>finalize</code> method causes
* the finalization of this object to be halted, but is otherwise
* ignored.
*
! * @throws Throwable the <code>Exception</code> raised by this method
*/
protected void finalize() throws Throwable { }
}
--- 503,553 ----
}
/**
* Called by the garbage collector on an object when garbage collection
* determines that there are no more references to the object.
! * A subclass overrides the {@code finalize} method to dispose of
* system resources or to perform other cleanup.
* <p>
! * The general contract of {@code finalize} is that it is invoked
* if and when the Java<font size="-2"><sup>TM</sup></font> virtual
* machine has determined that there is no longer any
* means by which this object can be accessed by any thread that has
* not yet died, except as a result of an action taken by the
* finalization of some other object or class which is ready to be
! * finalized. The {@code finalize} method may take any action, including
* making this object available again to other threads; the usual purpose
! * of {@code finalize}, however, is to perform cleanup actions before
* the object is irrevocably discarded. For example, the finalize method
* for an object that represents an input/output connection might perform
* explicit I/O transactions to break the connection before the object is
* permanently discarded.
* <p>
! * The {@code finalize} method of class {@code Object} performs no
* special action; it simply returns normally. Subclasses of
! * {@code Object} may override this definition.
* <p>
* The Java programming language does not guarantee which thread will
! * invoke the {@code finalize} method for any given object. It is
* guaranteed, however, that the thread that invokes finalize will not
* be holding any user-visible synchronization locks when finalize is
* invoked. If an uncaught exception is thrown by the finalize method,
* the exception is ignored and finalization of that object terminates.
* <p>
! * After the {@code finalize} method has been invoked for an object, no
* further action is taken until the Java virtual machine has again
* determined that there is no longer any means by which this object can
* be accessed by any thread that has not yet died, including possible
* actions by other objects or classes which are ready to be finalized,
* at which point the object may be discarded.
* <p>
! * The {@code finalize} method is never invoked more than once by a Java
* virtual machine for any given object.
* <p>
! * Any exception thrown by the {@code finalize} method causes
* the finalization of this object to be halted, but is otherwise
* ignored.
*
! * @throws Throwable the {@code Exception} raised by this method
*/
protected void finalize() throws Throwable { }
}