java.lang.ThreadGroup Maven / Gradle / Ivy
/*
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This work corresponds to the API signatures of JSR 219: Foundation
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*/
package java.lang;
import java.io.PrintStream;
/**
* 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.
*
* @author unascribed
* @version 1.55 07/27/01
* @since JDK1.0
*/
public class ThreadGroup
{
/**
* 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.
*
* @param name the name of the new thread group.
* @exception SecurityException if the current thread cannot create a
* thread in the specified thread group.
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public ThreadGroup(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.
*
* @param parent the parent thread group.
* @param name the name of the new thread group.
* @exception NullPointerException if the thread group argument is
* null.
* @exception SecurityException if the current thread cannot create a
* thread in the specified thread group.
* @see java.lang.SecurityException
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public ThreadGroup(java.lang.ThreadGroup parent, java.lang.String name) { }
/**
* Returns the name of this thread group.
*
* @return the name of this thread group.
* @since JDK1.0
*/
public final java.lang.String getName() {
return null;
}
/**
* 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.
*
* @return the parent of this thread group. The top-level thread group
* is the only thread group whose parent is null.
* @exception SecurityException if the current thread cannot modify
* this thread group.
* @see java.lang.ThreadGroup#checkAccess()
* @see java.lang.SecurityException
* @see java.lang.RuntimePermission
* @since JDK1.0
*/
public final java.lang.ThreadGroup getParent() {
return null;
}
/**
* Returns the maximum priority of this thread group. Threads that are
* part of this group cannot have a higher priority than the maximum
* priority.
*
* @return the maximum priority that a thread in this thread group
* can have.
* @see #setMaxPriority
* @since JDK1.0
*/
public final int getMaxPriority() {
return 0;
}
/**
* 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.
*
* @return true if this thread group is a daemon thread group;
* false otherwise.
* @since JDK1.0
*/
public final boolean isDaemon() {
return false;
}
/**
* Tests if this thread group has been destroyed.
*
* @return true if this object is destroyed
* @since JDK1.1
*/
public synchronized boolean isDestroyed() {
return false;
}
/**
* 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.
*
* @param daemon if true, marks this thread group as
* a daemon thread group; otherwise, marks this
* thread group as normal.
* @exception SecurityException if the current thread cannot modify
* this thread group.
* @see java.lang.SecurityException
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public final void setDaemon(boolean daemon) { }
/**
* 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
* {@link Thread#MIN_PRIORITY} or greater than
* {@link 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.
*
* @param pri the new priority of the thread group.
* @exception SecurityException if the current thread cannot modify
* this thread group.
* @see #getMaxPriority
* @see java.lang.SecurityException
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public final void setMaxPriority(int pri) { }
/**
* Tests if this thread group is either the thread group
* argument or one of its ancestor thread groups.
*
* @param g a thread group.
* @return true if this thread group is the thread group
* argument or one of its ancestor thread groups;
* false otherwise.
* @since JDK1.0
*/
public final boolean parentOf(java.lang.ThreadGroup g) {
return false;
}
/**
* 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.
*
* @exception SecurityException if the current thread is not allowed to
* access this thread group.
* @see java.lang.SecurityManager#checkAccess(java.lang.ThreadGroup)
* @since JDK1.0
*/
public final void checkAccess() { }
/**
* Returns an estimate of the number of active threads in this
* thread group.
*
* @return 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
*/
public int activeCount() {
return 0;
}
/**
* 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 should use the activeCount method to
* get an estimate of how big the array should be. If the array is
* too short to hold all the threads, the extra threads are silently
* ignored.
*
* @param list an array into which to place the list of threads.
* @return the number of threads put into the array.
* @exception SecurityException if the current thread does not
* have permission to enumerate this thread group.
* @see java.lang.ThreadGroup#activeCount()
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public int enumerate(java.lang.Thread[] list) {
return 0;
}
/**
* 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 should use the activeCount method to
* get an estimate of how big the array should be.
*
* @param list an array into which to place the list of threads.
* @param recurse a flag indicating whether also to include threads
* in thread groups that are subgroups of this
* thread group.
* @return the number of threads placed into the array.
* @exception SecurityException if the current thread does not
* have permission to enumerate this thread group.
* @see java.lang.ThreadGroup#activeCount()
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public int enumerate(java.lang.Thread[] list, boolean recurse) {
return 0;
}
/**
* Returns an estimate of the number of active groups in this
* thread group.
*
* @return the number of active thread groups with this thread group as
* an ancestor.
* @since JDK1.0
*/
public int activeGroupCount() {
return 0;
}
/**
* 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 should use the activeGroupCount
* method to get an estimate of how big the array should be. If the
* array is too short to hold all the thread groups, the extra thread
* groups are silently ignored.
*
* @param list an array into which to place the list of thread groups.
* @return the number of thread groups put into the array.
* @exception SecurityException if the current thread does not
* have permission to enumerate this thread group.
* @see java.lang.ThreadGroup#activeGroupCount()
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public int enumerate(java.lang.ThreadGroup[] list) {
return 0;
}
/**
* 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 should use the activeGroupCount
* method to get an estimate of how big the array should be.
*
* @param list an array into which to place the list of threads.
* @param recurse a flag indicating whether to recursively enumerate
* all included thread groups.
* @return the number of thread groups put into the array.
* @exception SecurityException if the current thread does not
* have permission to enumerate this thread group.
* @see java.lang.ThreadGroup#activeGroupCount()
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public int enumerate(java.lang.ThreadGroup[] list, boolean recurse) {
return 0;
}
/**
* 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.
*
* @exception SecurityException if the current thread is not allowed
* to access this thread group or any of the threads in
* the thread group.
* @see java.lang.Thread#interrupt()
* @see java.lang.SecurityException
* @see java.lang.ThreadGroup#checkAccess()
* @since 1.2
*/
public final void interrupt() { }
/**
* 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.
*
* @exception IllegalThreadStateException if the thread group is not
* empty or if the thread group has already been destroyed.
* @exception SecurityException if the current thread cannot modify this
* thread group.
* @see java.lang.ThreadGroup#checkAccess()
* @since JDK1.0
*/
public final void destroy() { }
/**
* Prints information about this thread group to the standard
* output. This method is useful only for debugging.
*
* @since JDK1.0
*/
public void list() { }
/**
* Called by the Java Virtual Machine when a thread in this
* thread group stops because of an uncaught exception.
*
* The uncaughtException method of
* ThreadGroup does the following:
*
* - If this thread group has a parent thread group, the
*
uncaughtException method of that parent is called
* with the same two arguments.
* - Otherwise, this method determines if the
Throwable
* argument is an instance of ThreadDeath. If so, nothing
* special is done. Otherwise, the Throwable's
* printStackTrace method is called to print a stack
* backtrace to the standard error stream.
*
*
* Applications can override this method in subclasses of
* ThreadGroup to provide alternative handling of
* uncaught exceptions.
*
* @param t the thread that is about to exit.
* @param e the uncaught exception.
* @see java.lang.System#err
* @see java.lang.ThreadDeath
* @see java.lang.Throwable#printStackTrace(java.io.PrintStream)
* @since JDK1.0
*/
public void uncaughtException(java.lang.Thread t, java.lang.Throwable e) { }
/**
* Returns a string representation of this Thread group.
*
* @return a string representation of this thread group.
* @since JDK1.0
*/
public java.lang.String toString() {
return null;
}
}