Adds a KeyEventDispatcher to this KeyboardFocusManager's dispatcher chain. This KeyboardFocusManager will request that each KeyEventDispatcher dispatch KeyEvents generated by the user before finally dispatching the KeyEvent itself. KeyEventDispatchers will be notified in the order in which they were added. Notifications will halt as soon as one KeyEventDispatcher returns true from its dispatchKeyEvent method. There is no limit to the total number of KeyEventDispatchers which can be added, nor to the number of times which a particular KeyEventDispatcher instance can be added.

If a null dispatcher is specified, no action is taken and no exception is thrown.

Adds a KeyEventPostProcessor to this KeyboardFocusManager's post- processor chain. After a KeyEvent has been dispatched to and handled by its target, KeyboardFocusManager will request that each KeyEventPostProcessor perform any necessary post-processing as part of the KeyEvent's final resolution. KeyEventPostProcessors will be notified in the order in which they were added; the current KeyboardFocusManager will be notified last. Notifications will halt as soon as one KeyEventPostProcessor returns true from its postProcessKeyEvent method. There is no limit to the the total number of KeyEventPostProcessors that can be added, nor to the number of times that a particular KeyEventPostProcessor instance can be added.

If a null post-processor is specified, no action is taken and no exception is thrown.

Adds a PropertyChangeListener to the listener list. The listener is registered for all bound properties of this class, including the following:

• whether the KeyboardFocusManager is currently managing focus for this application or applet's browser context ("managingFocus")
• the focus owner ("focusOwner")
• the permanent focus owner ("permanentFocusOwner")
• the focused Window ("focusedWindow")
• the active Window ("activeWindow")
• the default focus traversal policy ("defaultFocusTraversalPolicy")
• the Set of default FORWARD_TRAVERSAL_KEYS ("forwardDefaultFocusTraversalKeys")
• the Set of default BACKWARD_TRAVERSAL_KEYS ("backwardDefaultFocusTraversalKeys")
• the Set of default UP_CYCLE_TRAVERSAL_KEYS ("upCycleDefaultFocusTraversalKeys")
• the Set of default DOWN_CYCLE_TRAVERSAL_KEYS ("downCycleDefaultFocusTraversalKeys")
• the current focus cycle root ("currentFocusCycleRoot")

If listener is null, no exception is thrown and no action is performed.

Adds a PropertyChangeListener to the listener list for a specific property. The specified property may be user-defined, or one of the following:

• whether the KeyboardFocusManager is currently managing focus for this application or applet's browser context ("managingFocus")
• the focus owner ("focusOwner")
• the permanent focus owner ("permanentFocusOwner")
• the focused Window ("focusedWindow")
• the active Window ("activeWindow")
• the default focus traversal policy ("defaultFocusTraversalPolicy")
• the Set of default FORWARD_TRAVERSAL_KEYS ("forwardDefaultFocusTraversalKeys")
• the Set of default BACKWARD_TRAVERSAL_KEYS ("backwardDefaultFocusTraversalKeys")
• the Set of default UP_CYCLE_TRAVERSAL_KEYS ("upCycleDefaultFocusTraversalKeys")
• the Set of default DOWN_CYCLE_TRAVERSAL_KEYS ("downCycleDefaultFocusTraversalKeys")
• the current focus cycle root ("currentFocusCycleRoot")

If listener is null, no exception is thrown and no action is performed.

Adds a VetoableChangeListener to the listener list for a specific property. The specified property may be user-defined, or one of the following:

• the focus owner ("focusOwner")
• the permanent focus owner ("permanentFocusOwner")
• the focused Window ("focusedWindow")
• the active Window ("activeWindow")

If listener is null, no exception is thrown and no action is performed.

Adds a VetoableChangeListener to the listener list. The listener is registered for all vetoable properties of this class, including the following:

• the focus owner ("focusOwner")
• the permanent focus owner ("permanentFocusOwner")
• the focused Window ("focusedWindow")
• the active Window ("activeWindow")

If listener is null, no exception is thrown and no action is performed.

Clears the global focus owner at both the Java and native levels. If there exists a focus owner, that Component will receive a permanent FOCUS_LOST event. After this operation completes, the native windowing system will discard all user-generated KeyEvents until the user selects a new Component to receive focus, or a Component is given focus explicitly via a call to requestFocus(). This operation does not change the focused or active Windows.

This method is called by the AWT event dispatcher requesting that the current KeyboardFocusManager dispatch the specified event on its behalf. It is expected that all KeyboardFocusManagers will dispatch all FocusEvents, all WindowEvents related to focus, and all KeyEvents. These events should be dispatched based on the KeyboardFocusManager's notion of the focus owner and the focused and active Windows, sometimes overriding the source of the specified AWTEvent. Dispatching must be done using redispatchEvent to prevent the AWT event dispatcher from recursively requesting that the KeyboardFocusManager dispatch the event again. If this method returns false, then the AWT event dispatcher will attempt to dispatch the event itself.

This method is called by the current KeyboardFocusManager requesting that this KeyEventDispatcher dispatch the specified event on its behalf. This KeyEventDispatcher is free to retarget the event, consume it, dispatch it itself, or make other changes. This capability is typically used to deliver KeyEvents to Components other than the focus owner. This can be useful when navigating children of non-focusable Windows in an accessible environment, for example. Note that if a KeyEventDispatcher dispatches the KeyEvent itself, it must use redispatchEvent to prevent the current KeyboardFocusManager from recursively requesting that this KeyEventDispatcher dispatch the event again.

If an implementation of this method returns false, then the KeyEvent is passed to the next KeyEventDispatcher in the chain, ending with the current KeyboardFocusManager. If an implementation returns true, the KeyEvent is assumed to have been dispatched (although this need not be the case), and the current KeyboardFocusManager will take no further action with regard to the KeyEvent. In such a case, KeyboardFocusManager.dispatchEvent should return true as well. If an implementation consumes the KeyEvent, but returns false, the consumed event will still be passed to the next KeyEventDispatcher in the chain. It is important for developers to check whether the KeyEvent has been consumed before dispatching it to a target. By default, the current KeyboardFocusManager will not dispatch a consumed KeyEvent.

Moves the focus down one focus traversal cycle from the current focus owner, if and only if the current focus owner is a Container that is a focus cycle root. Typically, the focus owner is set to the current focus owner's default Component to focus, and the current focus cycle root is set to the current focus owner. If the current focus owner is not a Container that is a focus cycle root, then no focus traversal operation occurs.

Moves the focus down one focus traversal cycle. Typically, if aContainer is a focus cycle root, then the focus owner is set to aContainer's default Component to focus, and the current focus cycle root is set to aContainer. If aContainer is not a focus cycle root, then no focus traversal operation occurs.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

• It is reflexive: for any non-null reference value x, x.equals(x) should return true.
• It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
• It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
• It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
• For any non-null reference value x, x.equals(null) should return false.

The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference values x and y, this method returns true if and only if x and y refer to the same object (x == y has the value true).

Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.

Focuses the Component after the current focus owner.

Focuses the Component after aComponent, typically based on a FocusTraversalPolicy.

Focuses the Component before the current focus owner.

Focuses the Component before aComponent, typically based on a FocusTraversalPolicy.

Returns the active Window, if the active Window is in the same context as the calling thread. Only a Frame or a Dialog can be the active Window. The native windowing system may denote the active Window or its children with special decorations, such as a highlighted title bar. The active Window is always either the focused Window, or the first Frame or Dialog that is an owner of the focused Window.

Returns the runtime class of an object. That Class object is the object that is locked by static synchronized methods of the represented class.

Returns the current focus cycle root, if the current focus cycle root is in the same context as the calling thread. If the focus owner is itself a focus cycle root, then it may be ambiguous as to which Components represent the next and previous Components to focus during normal focus traversal. In that case, the current focus cycle root is used to differentiate among the possibilities.

This method is intended to be used only by KeyboardFocusManagers and focus implementations. It is not for general client use.

Returns the current KeyboardFocusManager instance for the calling thread's context.

Returns a Set of default focus traversal keys for a given traversal operation. This traversal key Set will be in effect on all Windows that have no such Set of their own explicitly defined. This Set will also be inherited, recursively, by any child Component of those Windows that has no such Set of its own explicitly defined. (See setDefaultFocusTraversalKeys for a full description of each operation.)

Returns the default FocusTraversalPolicy. Top-level components use this value on their creation to initialize their own focus traversal policy by explicit call to Container.setFocusTraversalPolicy.

Returns the focused Window, if the focused Window is in the same context as the calling thread. The focused Window is the Window that is or contains the focus owner.

Returns the focus owner, if the focus owner is in the same context as the calling thread. The focus owner is defined as the Component in an application that will typically receive all KeyEvents generated by the user. KeyEvents which map to the focus owner's focus traversal keys will not be delivered if focus traversal keys are enabled for the focus owner. In addition, KeyEventDispatchers may retarget or consume KeyEvents before they reach the focus owner.

Returns the permanent focus owner, if the permanent focus owner is in the same context as the calling thread. The permanent focus owner is defined as the last Component in an application to receive a permanent FOCUS_GAINED event. The focus owner and permanent focus owner are equivalent unless a temporary focus change is currently in effect. In such a situation, the permanent focus owner will again be the focus owner when the temporary focus change ends.

Returns an array of all the property change listeners registered on this keyboard focus manager.

Returns an array of all the PropertyChangeListeners associated with the named property.

Returns an array of all the vetoable change listeners registered on this keyboard focus manager.

Returns an array of all the VetoableChangeListeners associated with the named property.

Returns a hash code value for the object. This method is supported for the benefit of hashtables such as those provided by java.util.Hashtable.

The general contract of hashCode is:

• Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in 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.
• If two objects are equal according to the equals(Object) method, then calling the hashCode method on each of the two objects must produce the same integer result.
• It is not required that if two objects are unequal according to the method, then calling the 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 hashtables.

As much as is reasonably practical, the hashCode method defined by class 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^TM programming language.)

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 wait methods.

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 awakened thread enjoys no reliable privilege or disadvantage in being the next thread to lock this object.

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:

• By executing a synchronized instance method of that object.
• By executing the body of a synchronized statement that synchronizes on the object.
• For objects of type Class, by executing a synchronized static method of that class.

Only one thread at a time can own an object's monitor.

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 wait methods.

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.

This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.

This method is called by the current KeyboardFocusManager, requesting that this KeyEventPostProcessor perform any necessary post-processing which should be part of the KeyEvent's final resolution. At the time this method is invoked, typically the KeyEvent has already been dispatched to and handled by its target. However, if no Component in the application currently owns the focus, then the KeyEvent has not been dispatched to any Component. Typically, KeyEvent post-processing will be used to implement features which require global KeyEvent post-handling, such as menu shortcuts. Note that if a KeyEventPostProcessor wishes to dispatch the KeyEvent, it must use redispatchEvent to prevent the AWT from recursively requesting that this KeyEventPostProcessor perform post-processing of the event again.

If an implementation of this method returns false, then the KeyEvent is passed to the next KeyEventPostProcessor in the chain, ending with the current KeyboardFocusManager. If an implementation returns true, the KeyEvent is assumed to have been fully handled (although this need not be the case), and the AWT will take no further action with regard to the KeyEvent. If an implementation consumes the KeyEvent but returns false, the consumed event will still be passed to the next KeyEventPostProcessor in the chain. It is important for developers to check whether the KeyEvent has been consumed before performing any post-processing of the KeyEvent. By default, the current KeyboardFocusManager will perform no post- processing in response to a consumed KeyEvent.

This method initiates a focus traversal operation if and only if the KeyEvent represents a focus traversal key for the specified focusedComponent. It is expected that focusedComponent is the current focus owner, although this need not be the case. If it is not, focus traversal will nevertheless proceed as if focusedComponent were the current focus owner.

Redispatches an AWTEvent in such a way that the AWT event dispatcher will not recursively request that the KeyboardFocusManager, or any installed KeyEventDispatchers, dispatch the event again. Client implementations of dispatchEvent and client-defined KeyEventDispatchers must call redispatchEvent(target, e) instead of target.dispatchEvent(e) to dispatch an event.

This method is intended to be used only by KeyboardFocusManagers and KeyEventDispatchers. It is not for general client use.

Removes a KeyEventDispatcher which was previously added to this KeyboardFocusManager's dispatcher chain. This KeyboardFocusManager cannot itself be removed, unless it was explicitly re-registered via a call to addKeyEventDispatcher.

If a null dispatcher is specified, if the specified dispatcher is not in the dispatcher chain, or if this KeyboardFocusManager is specified without having been explicitly re-registered, no action is taken and no exception is thrown.

Removes a previously added KeyEventPostProcessor from this KeyboardFocusManager's post-processor chain. This KeyboardFocusManager cannot itself be entirely removed from the chain. Only additional references added via addKeyEventPostProcessor can be removed.

If a null post-processor is specified, if the specified post-processor is not in the post-processor chain, or if this KeyboardFocusManager is specified without having been explicitly added, no action is taken and no exception is thrown.

Removes a PropertyChangeListener from the listener list. This method should be used to remove the PropertyChangeListeners that were registered for all bound properties of this class.

If listener is null, no exception is thrown and no action is performed.

Removes a PropertyChangeListener from the listener list for a specific property. This method should be used to remove PropertyChangeListeners that were registered for a specific bound property.

If listener is null, no exception is thrown and no action is performed.

Removes a VetoableChangeListener from the listener list for a specific property. This method should be used to remove VetoableChangeListeners that were registered for a specific bound property.

If listener is null, no exception is thrown and no action is performed.

Removes a VetoableChangeListener from the listener list. This method should be used to remove the VetoableChangeListeners that were registered for all vetoable properties of this class.

If listener is null, no exception is thrown and no action is performed.

Sets the current KeyboardFocusManager instance for the calling thread's context. If null is specified, then the current KeyboardFocusManager is replaced with a new instance of DefaultKeyboardFocusManager.

If a SecurityManager is installed, the calling thread must be granted the AWTPermission "replaceKeyboardFocusManager" in order to replace the the current KeyboardFocusManager. If this permission is not granted, this method will throw a SecurityException, and the current KeyboardFocusManager will be unchanged.

Sets the default focus traversal keys for a given traversal operation. This traversal key Set will be in effect on all Windows that have no such Set of their own explicitly defined. This Set will also be inherited, recursively, by any child Component of those Windows that has no such Set of its own explicitly defined.

The default values for the default focus traversal keys are implementation-dependent. Sun recommends that all implementations for a particular native platform use the same default values. The recommendations for Windows and Unix are listed below. These recommendations are used in the Sun AWT implementations.

Identifier	Meaning	Default
KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS	Normal forward keyboard traversal	TAB on KEY_PRESSED, CTRL-TAB on KEY_PRESSED
KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS	Normal reverse keyboard traversal	SHIFT-TAB on KEY_PRESSED, CTRL-SHIFT-TAB on KEY_PRESSED
KeyboardFocusManager.UP_CYCLE_TRAVERSAL_KEYS	Go up one focus traversal cycle	none
KeyboardFocusManager.DOWN_CYCLE_TRAVERSAL_KEYS	Go down one focus traversal cycle	none

To disable a traversal key, use an empty Set; Collections.EMPTY_SET is recommended.

Using the AWTKeyStroke API, client code can specify on which of two specific KeyEvents, KEY_PRESSED or KEY_RELEASED, the focus traversal operation will occur. Regardless of which KeyEvent is specified, however, all KeyEvents related to the focus traversal key, including the associated KEY_TYPED event, will be consumed, and will not be dispatched to any Component. It is a runtime error to specify a KEY_TYPED event as mapping to a focus traversal operation, or to map the same event to multiple default focus traversal operations.

Sets the default FocusTraversalPolicy. Top-level components use this value on their creation to initialize their own focus traversal policy by explicit call to Container.setFocusTraversalPolicy. Note: this call doesn't affect already created components as they have their policy initialized. Only new components will use this policy as their default policy.

Sets the current focus cycle root. If the focus owner is itself a focus cycle root, then it may be ambiguous as to which Components represent the next and previous Components to focus during normal focus traversal. In that case, the current focus cycle root is used to differentiate among the possibilities.

This method is intended to be used only by KeyboardFocusManagers and focus implementations. It is not for general client use.

Returns a string representation of the object. In general, the 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.

The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', 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:

 getClass().getName() + '@' + Integer.toHexString(hashCode())
 

Moves the focus up one focus traversal cycle from the current focus owner. Typically, the new focus owner is set to the current focus owner's focus cycle root, and the current focus cycle root is set to the new focus owner's focus cycle root. If, however, the current focus owner's focus cycle root is a Window, then typically the focus owner is set to the focus cycle root's default Component to focus, and the current focus cycle root is unchanged.

Moves the focus up one focus traversal cycle. Typically, the focus owner is set to aComponent's focus cycle root, and the current focus cycle root is set to the new focus owner's focus cycle root. If, however, aComponent's focus cycle root is a Window, then typically the focus owner is set to the Window's default Component to focus, and the current focus cycle root is unchanged.

Causes current thread to wait until another thread invokes the method or the method for this object. In other words, this method behaves exactly as if it simply performs the call wait(0).

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 notify method or the notifyAll method. The thread then waits until it can re-obtain ownership of the monitor and resumes execution.

As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:

     synchronized (obj) {
         while (<condition does not hold>)
             obj.wait();
         ... // Perform action appropriate to condition
     }
 

This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.

Causes current thread to wait until either another thread invokes the method or the method for this object, or a specified amount of time has elapsed.

The current thread must own this object's monitor.

This method causes the current thread (call it T) to place itself in the wait set for this object and then to relinquish any and all synchronization claims on this object. Thread T becomes disabled for thread scheduling purposes and lies dormant until one of four things happens:

• Some other thread invokes the notify method for this object and thread T happens to be arbitrarily chosen as the thread to be awakened.
• Some other thread invokes the notifyAll method for this object.
• Some other thread interrupts thread T.
• The specified amount of real time has elapsed, more or less. If timeout is zero, however, then real time is not taken into consideration and the thread simply waits until notified.

The thread T 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 wait method was invoked. Thread T then returns from the invocation of the wait method. Thus, on return from the wait method, the synchronization state of the object and of thread T is exactly as it was when the wait method was invoked.

A thread can also wake up without being notified, interrupted, or timing out, a so-called spurious wakeup. While this will rarely occur in practice, applications must guard against it by testing for the condition that should have caused the thread to be awakened, and continuing to wait if the condition is not satisfied. In other words, waits should always occur in loops, like this one:

     synchronized (obj) {
         while (<condition does not hold>)
             obj.wait(timeout);
         ... // Perform action appropriate to condition
     }
 

(For more information on this topic, see Section 3.2.3 in Doug Lea's "Concurrent Programming in Java (Second Edition)" (Addison-Wesley, 2000), or Item 50 in Joshua Bloch's "Effective Java Programming Language Guide" (Addison-Wesley, 2001).

If the current thread is interrupted by another thread while it is waiting, then an InterruptedException is thrown. This exception is not thrown until the lock status of this object has been restored as described above.

Note that the 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.

This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.

Causes current thread to wait until another thread invokes the method or the method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.

This method is similar to the 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:

 1000000*timeout+nanos

In all other respects, this method does the same thing as the method of one argument. In particular, wait(0, 0) means the same thing as wait(0).

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:

• Another thread notifies threads waiting on this object's monitor to wake up either through a call to the notify method or the notifyAll method.
• The timeout period, specified by timeout milliseconds plus nanos nanoseconds arguments, has elapsed.

The thread then waits until it can re-obtain ownership of the monitor and resumes execution.

As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:

     synchronized (obj) {
         while (<condition does not hold>)
             obj.wait(timeout, nanos);
         ... // Perform action appropriate to condition
     }
 

This method should only be called by a thread that is the owner of this object's monitor. See the notify method for a description of the ways in which a thread can become the owner of a monitor.