java.lang
Class ThreadGroup

java.lang.Object sample code for java.lang.Object definition code for java.lang.Object 
  extended by java.lang.ThreadGroup
All Implemented Interfaces:
Thread.UncaughtExceptionHandler sample code for java.lang.Thread.UncaughtExceptionHandler definition code for java.lang.Thread.UncaughtExceptionHandler

public class ThreadGroup
extends Object sample code for java.lang.Object definition code for java.lang.Object
implements Thread.UncaughtExceptionHandler sample code for java.lang.Thread.UncaughtExceptionHandler definition code for java.lang.Thread.UncaughtExceptionHandler

A thread group represents a set of threads. In addition, a thread group can also include other thread groups. The thread groups form a tree in which every thread group except the initial thread group has a parent.

A thread is allowed to access information about its own thread group, but not to access information about its thread group's parent thread group or any other thread groups.

Since:
JDK1.0

Constructor Summary
ThreadGroup sample code for java.lang.ThreadGroup.ThreadGroup(java.lang.String) definition code for java.lang.ThreadGroup.ThreadGroup(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Constructs a new thread group.
ThreadGroup sample code for java.lang.ThreadGroup.ThreadGroup(java.lang.ThreadGroup, java.lang.String) definition code for java.lang.ThreadGroup.ThreadGroup(java.lang.ThreadGroup, java.lang.String) (ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup  parent, String sample code for java.lang.String definition code for java.lang.String  name)
          Creates a new thread group.
 
Method Summary
 int activeCount sample code for java.lang.ThreadGroup.activeCount() definition code for java.lang.ThreadGroup.activeCount() ()
          Returns an estimate of the number of active threads in this thread group.
 int activeGroupCount sample code for java.lang.ThreadGroup.activeGroupCount() definition code for java.lang.ThreadGroup.activeGroupCount() ()
          Returns an estimate of the number of active groups in this thread group.
 boolean allowThreadSuspension sample code for java.lang.ThreadGroup.allowThreadSuspension(boolean) definition code for java.lang.ThreadGroup.allowThreadSuspension(boolean) (boolean b)
          Deprecated. The definition of this call depends on suspend() sample code for java.lang.ThreadGroup.suspend() definition code for java.lang.ThreadGroup.suspend() , which is deprecated. Further, the behavior of this call was never specified.
 void checkAccess sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess() ()
          Determines if the currently running thread has permission to modify this thread group.
 void destroy sample code for java.lang.ThreadGroup.destroy() definition code for java.lang.ThreadGroup.destroy() ()
          Destroys this thread group and all of its subgroups.
 int enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.Thread[]) definition code for java.lang.ThreadGroup.enumerate(java.lang.Thread[]) (Thread sample code for java.lang.Thread definition code for java.lang.Thread [] list)
          Copies into the specified array every active thread in this thread group and its subgroups.
 int enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.Thread[], boolean) definition code for java.lang.ThreadGroup.enumerate(java.lang.Thread[], boolean) (Thread sample code for java.lang.Thread definition code for java.lang.Thread [] list, boolean recurse)
          Copies into the specified array every active thread in this thread group.
 int enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[]) definition code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[]) (ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup [] list)
          Copies into the specified array references to every active subgroup in this thread group.
 int enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[], boolean) definition code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[], boolean) (ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup [] list, boolean recurse)
          Copies into the specified array references to every active subgroup in this thread group.
 int getMaxPriority sample code for java.lang.ThreadGroup.getMaxPriority() definition code for java.lang.ThreadGroup.getMaxPriority() ()
          Returns the maximum priority of this thread group.
 String sample code for java.lang.String definition code for java.lang.String getName sample code for java.lang.ThreadGroup.getName() definition code for java.lang.ThreadGroup.getName() ()
          Returns the name of this thread group.
 ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup getParent sample code for java.lang.ThreadGroup.getParent() definition code for java.lang.ThreadGroup.getParent() ()
          Returns the parent of this thread group.
 void interrupt sample code for java.lang.ThreadGroup.interrupt() definition code for java.lang.ThreadGroup.interrupt() ()
          Interrupts all threads in this thread group.
 boolean isDaemon sample code for java.lang.ThreadGroup.isDaemon() definition code for java.lang.ThreadGroup.isDaemon() ()
          Tests if this thread group is a daemon thread group.
 boolean isDestroyed sample code for java.lang.ThreadGroup.isDestroyed() definition code for java.lang.ThreadGroup.isDestroyed() ()
          Tests if this thread group has been destroyed.
 void list sample code for java.lang.ThreadGroup.list() definition code for java.lang.ThreadGroup.list() ()
          Prints information about this thread group to the standard output.
 boolean parentOf sample code for java.lang.ThreadGroup.parentOf(java.lang.ThreadGroup) definition code for java.lang.ThreadGroup.parentOf(java.lang.ThreadGroup) (ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup  g)
          Tests if this thread group is either the thread group argument or one of its ancestor thread groups.
 void resume sample code for java.lang.ThreadGroup.resume() definition code for java.lang.ThreadGroup.resume() ()
          Deprecated. This method is used solely in conjunction with Thread.suspend and ThreadGroup.suspend, both of which have been deprecated, as they are inherently deadlock-prone. See Thread.suspend() sample code for java.lang.Thread.suspend() definition code for java.lang.Thread.suspend() for details.
 void setDaemon sample code for java.lang.ThreadGroup.setDaemon(boolean) definition code for java.lang.ThreadGroup.setDaemon(boolean) (boolean daemon)
          Changes the daemon status of this thread group.
 void setMaxPriority sample code for java.lang.ThreadGroup.setMaxPriority(int) definition code for java.lang.ThreadGroup.setMaxPriority(int) (int pri)
          Sets the maximum priority of the group.
 void stop sample code for java.lang.ThreadGroup.stop() definition code for java.lang.ThreadGroup.stop() ()
          Deprecated. This method is inherently unsafe. See Thread.stop() sample code for java.lang.Thread.stop() definition code for java.lang.Thread.stop() for details.
 void suspend sample code for java.lang.ThreadGroup.suspend() definition code for java.lang.ThreadGroup.suspend() ()
          Deprecated. This method is inherently deadlock-prone. See Thread.suspend() sample code for java.lang.Thread.suspend() definition code for java.lang.Thread.suspend() for details.
 String sample code for java.lang.String definition code for java.lang.String toString sample code for java.lang.ThreadGroup.toString() definition code for java.lang.ThreadGroup.toString() ()
          Returns a string representation of this Thread group.
 void uncaughtException sample code for java.lang.ThreadGroup.uncaughtException(java.lang.Thread, java.lang.Throwable) definition code for java.lang.ThreadGroup.uncaughtException(java.lang.Thread, java.lang.Throwable) (Thread sample code for java.lang.Thread definition code for java.lang.Thread  t, Throwable sample code for java.lang.Throwable definition code for java.lang.Throwable  e)
          Called by the Java Virtual Machine when a thread in this thread group stops because of an uncaught exception, and the thread does not have a specific Thread.UncaughtExceptionHandler sample code for java.lang.Thread.UncaughtExceptionHandler definition code for java.lang.Thread.UncaughtExceptionHandler installed.
 
Methods inherited from class java.lang.Object sample code for java.lang.Object definition code for java.lang.Object
clone sample code for java.lang.Object.clone() definition code for java.lang.Object.clone() , equals sample code for java.lang.Object.equals(java.lang.Object) definition code for java.lang.Object.equals(java.lang.Object) , finalize sample code for java.lang.Object.finalize() definition code for java.lang.Object.finalize() , getClass sample code for java.lang.Object.getClass() definition code for java.lang.Object.getClass() , hashCode sample code for java.lang.Object.hashCode() definition code for java.lang.Object.hashCode() , notify sample code for java.lang.Object.notify() definition code for java.lang.Object.notify() , notifyAll sample code for java.lang.Object.notifyAll() definition code for java.lang.Object.notifyAll() , wait sample code for java.lang.Object.wait() definition code for java.lang.Object.wait() , wait sample code for java.lang.Object.wait(long) definition code for java.lang.Object.wait(long) , wait sample code for java.lang.Object.wait(long, int) definition code for java.lang.Object.wait(long, int)
 

Constructor Detail

ThreadGroup sample code for java.lang.ThreadGroup(java.lang.String) definition code for java.lang.ThreadGroup(java.lang.String)

public ThreadGroup(String sample code for java.lang.String definition code for java.lang.String  name)
Constructs a new thread group. The parent of this new group is the thread group of the currently running thread.

The checkAccess method of the parent thread group is called with no arguments; this may result in a security exception.

Parameters:
name - the name of the new thread group.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread cannot create a thread in the specified thread group.
Since:
JDK1.0
See Also:
checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

ThreadGroup sample code for java.lang.ThreadGroup(java.lang.ThreadGroup, java.lang.String) definition code for java.lang.ThreadGroup(java.lang.ThreadGroup, java.lang.String)

public ThreadGroup(ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup  parent,
                   String sample code for java.lang.String definition code for java.lang.String  name)
Creates a new thread group. The parent of this new group is the specified thread group.

The checkAccess method of the parent thread group is called with no arguments; this may result in a security exception.

Parameters:
parent - the parent thread group.
name - the name of the new thread group.
Throws:
NullPointerException sample code for java.lang.NullPointerException definition code for java.lang.NullPointerException - if the thread group argument is null.
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread cannot create a thread in the specified thread group.
Since:
JDK1.0
See Also:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()
Method Detail

getName sample code for java.lang.ThreadGroup.getName() definition code for java.lang.ThreadGroup.getName()

public final String sample code for java.lang.String definition code for java.lang.String  getName()
Returns the name of this thread group.

Returns:
the name of this thread group.
Since:
JDK1.0

getParent sample code for java.lang.ThreadGroup.getParent() definition code for java.lang.ThreadGroup.getParent()

public final ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup  getParent()
Returns the parent of this thread group.

First, if the parent is not null, the checkAccess method of the parent thread group is called with no arguments; this may result in a security exception.

Returns:
the parent of this thread group. The top-level thread group is the only thread group whose parent is null.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread cannot modify this thread group.
Since:
JDK1.0
See Also:
checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess() , SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , RuntimePermission sample code for java.lang.RuntimePermission definition code for java.lang.RuntimePermission

getMaxPriority sample code for java.lang.ThreadGroup.getMaxPriority() definition code for java.lang.ThreadGroup.getMaxPriority()

public final int getMaxPriority()
Returns the maximum priority of this thread group. Threads that are part of this group cannot have a higher priority than the maximum priority.

Returns:
the maximum priority that a thread in this thread group can have.
Since:
JDK1.0
See Also:
setMaxPriority(int) sample code for java.lang.ThreadGroup.setMaxPriority(int) definition code for java.lang.ThreadGroup.setMaxPriority(int)

isDaemon sample code for java.lang.ThreadGroup.isDaemon() definition code for java.lang.ThreadGroup.isDaemon()

public final boolean isDaemon()
Tests if this thread group is a daemon thread group. A daemon thread group is automatically destroyed when its last thread is stopped or its last thread group is destroyed.

Returns:
true if this thread group is a daemon thread group; false otherwise.
Since:
JDK1.0

isDestroyed sample code for java.lang.ThreadGroup.isDestroyed() definition code for java.lang.ThreadGroup.isDestroyed()

public boolean isDestroyed()
Tests if this thread group has been destroyed.

Returns:
true if this object is destroyed
Since:
JDK1.1

setDaemon sample code for java.lang.ThreadGroup.setDaemon(boolean) definition code for java.lang.ThreadGroup.setDaemon(boolean)

public final void setDaemon(boolean daemon)
Changes the daemon status of this thread group.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

A daemon thread group is automatically destroyed when its last thread is stopped or its last thread group is destroyed.

Parameters:
daemon - if true, marks this thread group as a daemon thread group; otherwise, marks this thread group as normal.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread cannot modify this thread group.
Since:
JDK1.0
See Also:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

setMaxPriority sample code for java.lang.ThreadGroup.setMaxPriority(int) definition code for java.lang.ThreadGroup.setMaxPriority(int)

public final void setMaxPriority(int pri)
Sets the maximum priority of the group. Threads in the thread group that already have a higher priority are not affected.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

If the pri argument is less than Thread.MIN_PRIORITY sample code for java.lang.Thread.MIN_PRIORITY definition code for java.lang.Thread.MIN_PRIORITY or greater than Thread.MAX_PRIORITY sample code for java.lang.Thread.MAX_PRIORITY definition code for java.lang.Thread.MAX_PRIORITY , the maximum priority of the group remains unchanged.

Otherwise, the priority of this ThreadGroup object is set to the smaller of the specified pri and the maximum permitted priority of the parent of this thread group. (If this thread group is the system thread group, which has no parent, then its maximum priority is simply set to pri.) Then this method is called recursively, with pri as its argument, for every thread group that belongs to this thread group.

Parameters:
pri - the new priority of the thread group.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread cannot modify this thread group.
Since:
JDK1.0
See Also:
getMaxPriority() sample code for java.lang.ThreadGroup.getMaxPriority() definition code for java.lang.ThreadGroup.getMaxPriority() , SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

parentOf sample code for java.lang.ThreadGroup.parentOf(java.lang.ThreadGroup) definition code for java.lang.ThreadGroup.parentOf(java.lang.ThreadGroup)

public final boolean parentOf(ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup  g)
Tests if this thread group is either the thread group argument or one of its ancestor thread groups.

Parameters:
g - a thread group.
Returns:
true if this thread group is the thread group argument or one of its ancestor thread groups; false otherwise.
Since:
JDK1.0

checkAccess sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

public final void checkAccess()
Determines if the currently running thread has permission to modify this thread group.

If there is a security manager, its checkAccess method is called with this thread group as its argument. This may result in throwing a SecurityException.

Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread is not allowed to access this thread group.
Since:
JDK1.0
See Also:
SecurityManager.checkAccess(java.lang.ThreadGroup) sample code for java.lang.SecurityManager.checkAccess(java.lang.ThreadGroup) definition code for java.lang.SecurityManager.checkAccess(java.lang.ThreadGroup)

activeCount sample code for java.lang.ThreadGroup.activeCount() definition code for java.lang.ThreadGroup.activeCount()

public int activeCount()
Returns an estimate of the number of active threads in this thread group. The result might not reflect concurrent activity, and might be affected by the presence of certain system threads.

Due to the inherently imprecise nature of the result, it is recommended that this method only be used for informational purposes.

Returns:
an estimate of the number of active threads in this thread group and in any other thread group that has this thread group as an ancestor.
Since:
JDK1.0

enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.Thread[]) definition code for java.lang.ThreadGroup.enumerate(java.lang.Thread[])

public int enumerate(Thread sample code for java.lang.Thread definition code for java.lang.Thread [] list)
Copies into the specified array every active thread in this thread group and its subgroups.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

An application might use the activeCount method to get an estimate of how big the array should be, however if the array is too short to hold all the threads, the extra threads are silently ignored. If it is critical to obtain every active thread in this thread group and its subgroups, the caller should verify that the returned int value is strictly less than the length of list.

Due to the inherent race condition in this method, it is recommended that the method only be used for informational purposes.

Parameters:
list - an array into which to place the list of threads.
Returns:
the number of threads put into the array.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread does not have permission to enumerate this thread group.
Since:
JDK1.0
See Also:
activeCount() sample code for java.lang.ThreadGroup.activeCount() definition code for java.lang.ThreadGroup.activeCount() , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.Thread[], boolean) definition code for java.lang.ThreadGroup.enumerate(java.lang.Thread[], boolean)

public int enumerate(Thread sample code for java.lang.Thread definition code for java.lang.Thread [] list,
                     boolean recurse)
Copies into the specified array every active thread in this thread group. If the recurse flag is true, references to every active thread in this thread's subgroups are also included. If the array is too short to hold all the threads, the extra threads are silently ignored.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

An application might use the activeCount method to get an estimate of how big the array should be, however if the array is too short to hold all the threads, the extra threads are silently ignored. If it is critical to obtain every active thread in this thread group, the caller should verify that the returned int value is strictly less than the length of list.

Due to the inherent race condition in this method, it is recommended that the method only be used for informational purposes.

Parameters:
list - an array into which to place the list of threads.
recurse - a flag indicating whether also to include threads in thread groups that are subgroups of this thread group.
Returns:
the number of threads placed into the array.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread does not have permission to enumerate this thread group.
Since:
JDK1.0
See Also:
activeCount() sample code for java.lang.ThreadGroup.activeCount() definition code for java.lang.ThreadGroup.activeCount() , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

activeGroupCount sample code for java.lang.ThreadGroup.activeGroupCount() definition code for java.lang.ThreadGroup.activeGroupCount()

public int activeGroupCount()
Returns an estimate of the number of active groups in this thread group. The result might not reflect concurrent activity.

Due to the inherently imprecise nature of the result, it is recommended that this method only be used for informational purposes.

Returns:
the number of active thread groups with this thread group as an ancestor.
Since:
JDK1.0

enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[]) definition code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[])

public int enumerate(ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup [] list)
Copies into the specified array references to every active subgroup in this thread group.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

An application might use the activeGroupCount method to get an estimate of how big the array should be, however if the array is too short to hold all the thread groups, the extra thread groups are silently ignored. If it is critical to obtain every active subgroup in this thread group, the caller should verify that the returned int value is strictly less than the length of list.

Due to the inherent race condition in this method, it is recommended that the method only be used for informational purposes.

Parameters:
list - an array into which to place the list of thread groups.
Returns:
the number of thread groups put into the array.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread does not have permission to enumerate this thread group.
Since:
JDK1.0
See Also:
activeGroupCount() sample code for java.lang.ThreadGroup.activeGroupCount() definition code for java.lang.ThreadGroup.activeGroupCount() , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

enumerate sample code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[], boolean) definition code for java.lang.ThreadGroup.enumerate(java.lang.ThreadGroup[], boolean)

public int enumerate(ThreadGroup sample code for java.lang.ThreadGroup definition code for java.lang.ThreadGroup [] list,
                     boolean recurse)
Copies into the specified array references to every active subgroup in this thread group. If the recurse flag is true, references to all active subgroups of the subgroups and so forth are also included.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

An application might use the activeGroupCount method to get an estimate of how big the array should be, however if the array is too short to hold all the thread groups, the extra thread groups are silently ignored. If it is critical to obtain every active subgroup in this thread group, the caller should verify that the returned int value is strictly less than the length of list.

Due to the inherent race condition in this method, it is recommended that the method only be used for informational purposes.

Parameters:
list - an array into which to place the list of threads.
recurse - a flag indicating whether to recursively enumerate all included thread groups.
Returns:
the number of thread groups put into the array.
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread does not have permission to enumerate this thread group.
Since:
JDK1.0
See Also:
activeGroupCount() sample code for java.lang.ThreadGroup.activeGroupCount() definition code for java.lang.ThreadGroup.activeGroupCount() , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

stop sample code for java.lang.ThreadGroup.stop() definition code for java.lang.ThreadGroup.stop()

@Deprecated
public final void stop()
Deprecated. This method is inherently unsafe. See Thread.stop() sample code for java.lang.Thread.stop() definition code for java.lang.Thread.stop() for details.

Stops all threads in this thread group.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

This method then calls the stop method on all the threads in this thread group and in all of its subgroups.

Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread is not allowed to access this thread group or any of the threads in the thread group.
Since:
JDK1.0
See Also:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , Thread.stop() sample code for java.lang.Thread.stop() definition code for java.lang.Thread.stop() , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

interrupt sample code for java.lang.ThreadGroup.interrupt() definition code for java.lang.ThreadGroup.interrupt()

public final void interrupt()
Interrupts all threads in this thread group.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

This method then calls the interrupt method on all the threads in this thread group and in all of its subgroups.

Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread is not allowed to access this thread group or any of the threads in the thread group.
Since:
1.2
See Also:
Thread.interrupt() sample code for java.lang.Thread.interrupt() definition code for java.lang.Thread.interrupt() , SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

suspend sample code for java.lang.ThreadGroup.suspend() definition code for java.lang.ThreadGroup.suspend()

@Deprecated
public final void suspend()
Deprecated. This method is inherently deadlock-prone. See Thread.suspend() sample code for java.lang.Thread.suspend() definition code for java.lang.Thread.suspend() for details.

Suspends all threads in this thread group.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

This method then calls the suspend method on all the threads in this thread group and in all of its subgroups.

Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread is not allowed to access this thread group or any of the threads in the thread group.
Since:
JDK1.0
See Also:
Thread.suspend() sample code for java.lang.Thread.suspend() definition code for java.lang.Thread.suspend() , SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

resume sample code for java.lang.ThreadGroup.resume() definition code for java.lang.ThreadGroup.resume()

@Deprecated
public final void resume()
Deprecated. This method is used solely in conjunction with Thread.suspend and ThreadGroup.suspend, both of which have been deprecated, as they are inherently deadlock-prone. See Thread.suspend() sample code for java.lang.Thread.suspend() definition code for java.lang.Thread.suspend() for details.

Resumes all threads in this thread group.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

This method then calls the resume method on all the threads in this thread group and in all of its sub groups.

Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread is not allowed to access this thread group or any of the threads in the thread group.
Since:
JDK1.0
See Also:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException , Thread.resume() sample code for java.lang.Thread.resume() definition code for java.lang.Thread.resume() , checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

destroy sample code for java.lang.ThreadGroup.destroy() definition code for java.lang.ThreadGroup.destroy()

public final void destroy()
Destroys this thread group and all of its subgroups. This thread group must be empty, indicating that all threads that had been in this thread group have since stopped.

First, the checkAccess method of this thread group is called with no arguments; this may result in a security exception.

Throws:
IllegalThreadStateException sample code for java.lang.IllegalThreadStateException definition code for java.lang.IllegalThreadStateException - if the thread group is not empty or if the thread group has already been destroyed.
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - if the current thread cannot modify this thread group.
Since:
JDK1.0
See Also:
checkAccess() sample code for java.lang.ThreadGroup.checkAccess() definition code for java.lang.ThreadGroup.checkAccess()

list sample code for java.lang.ThreadGroup.list() definition code for java.lang.ThreadGroup.list()

public void list()
Prints information about this thread group to the standard output. This method is useful only for debugging.

Since:
JDK1.0

uncaughtException sample code for java.lang.ThreadGroup.uncaughtException(java.lang.Thread, java.lang.Throwable) definition code for java.lang.ThreadGroup.uncaughtException(java.lang.Thread, java.lang.Throwable)

public void uncaughtException(Thread sample code for java.lang.Thread definition code for java.lang.Thread  t,
                              Throwable sample code for java.lang.Throwable definition code for java.lang.Throwable  e)
Called by the Java Virtual Machine when a thread in this thread group stops because of an uncaught exception, and the thread does not have a specific Thread.UncaughtExceptionHandler sample code for java.lang.Thread.UncaughtExceptionHandler definition code for java.lang.Thread.UncaughtExceptionHandler installed.

The uncaughtException method of ThreadGroup does the following:

Applications can override this method in subclasses of ThreadGroup to provide alternative handling of uncaught exceptions.

Specified by:
uncaughtException sample code for java.lang.Thread.UncaughtExceptionHandler.uncaughtException(java.lang.Thread, java.lang.Throwable) definition code for java.lang.Thread.UncaughtExceptionHandler.uncaughtException(java.lang.Thread, java.lang.Throwable) in interface Thread.UncaughtExceptionHandler sample code for java.lang.Thread.UncaughtExceptionHandler definition code for java.lang.Thread.UncaughtExceptionHandler
Parameters:
t - the thread that is about to exit.
e - the uncaught exception.
Since:
JDK1.0

allowThreadSuspension sample code for java.lang.ThreadGroup.allowThreadSuspension(boolean) definition code for java.lang.ThreadGroup.allowThreadSuspension(boolean)

@Deprecated
public boolean allowThreadSuspension(boolean b)
Deprecated. The definition of this call depends on suspend() sample code for java.lang.ThreadGroup.suspend() definition code for java.lang.ThreadGroup.suspend() , which is deprecated. Further, the behavior of this call was never specified.

Used by VM to control lowmem implicit suspension.

Parameters:
b - boolean to allow or disallow suspension
Returns:
true on success
Since:
JDK1.1

toString sample code for java.lang.ThreadGroup.toString() definition code for java.lang.ThreadGroup.toString()

public String sample code for java.lang.String definition code for java.lang.String  toString()
Returns a string representation of this Thread group.

Overrides:
toString sample code for java.lang.Object.toString() definition code for java.lang.Object.toString() in class Object sample code for java.lang.Object definition code for java.lang.Object
Returns:
a string representation of this thread group.
Since:
JDK1.0