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package com.sun.jdi;

import java.util.List;


A thread group object from the target VM. A ThreadGroupReference is an ObjectReference with additional access to threadgroup-specific information from the target VM. 
Author:Robert Field, Gordon Hirsch, James McIlree
Since: 1.3
/**
 * A thread group object from the target VM.
 * A ThreadGroupReference is an {@link ObjectReference} with additional
 * access to threadgroup-specific information from the target VM.
 *
 * @author Robert Field
 * @author Gordon Hirsch
 * @author James McIlree
 * @since  1.3
 */
public interface ThreadGroupReference extends ObjectReference
{
    
Returns the name of this thread group.

Returns:the string containing the thread group name.
/**
     * Returns the name of this thread group.
     *
     * @return the string containing the thread group name.
     */
    String name();

    
Returns the parent of this thread group.

Returns:a ThreadGroupReference mirroring the parent of this thread group in the target VM, or null if this is a top-level thread group.
/**
     * Returns the parent of this thread group.
     *
     * @return a {@link ThreadGroupReference} mirroring the parent of this
     * thread group in the target VM, or null if this is a top-level
     * thread group.
     */
    ThreadGroupReference parent();

    
Suspends all threads in this thread group. Each thread in this group and in all of its subgroups will be suspended as described in ThreadReference.suspend. This is not guaranteed to be an atomic operation; if the target VM is not interrupted at the time this method is called, it is possible that new threads will be created between the time that threads are enumerated and all of them have been suspended. 
Throws:
/**
     * Suspends all threads in this thread group. Each thread
     * in this group and in all of its subgroups will be
     * suspended as described in {@link ThreadReference#suspend}.
     * This is not guaranteed to be an atomic
     * operation; if the target VM is not interrupted at the time
     * this method is
     * called, it is possible that new threads will be created
     * between the time that threads are enumerated and all of them
     * have been suspended.
     * @throws VMCannotBeModifiedException if the VirtualMachine is read-only - see {@link VirtualMachine#canBeModified()}.
     */
    void suspend();

    
Resumes all threads in this thread group. Each thread in this group and in all of its subgroups will be resumed as described in ThreadReference.resume. 
Throws:
/**
     * Resumes all threads in this thread group. Each thread
     * in this group and in all of its subgroups will be
     * resumed as described in {@link ThreadReference#resume}.
     * @throws VMCannotBeModifiedException if the VirtualMachine is read-only - see {@link VirtualMachine#canBeModified()}.
     */
    void resume();

    
Returns a List containing a ThreadReference for each live thread in this thread group. Only the live threads in this immediate thread group (and not its subgroups) are returned. A thread is alive if it has been started and has not yet been stopped. 
Returns:a List of ThreadReference objects mirroring the live threads from this thread group in the target VM.
/**
     * Returns a List containing a {@link ThreadReference} for each live thread
     * in this thread group. Only the live threads in this immediate thread group
     * (and not its subgroups) are returned.  A thread is alive if it
     * has been started and has not yet been stopped.
     *
     * @return a List of {@link ThreadReference} objects mirroring the
     * live threads from this thread group in the target VM.
     */
    List<ThreadReference> threads();

    
Returns a List containing each active ThreadGroupReference in this thread group. Only the active thread groups in this immediate thread group (and not its subgroups) are returned. See java.lang.ThreadGroup
for information about 'active' ThreadGroups.

Returns:a List of ThreadGroupReference objects mirroring the active thread groups from this thread group in the target VM.
/**
     * Returns a List containing each active {@link ThreadGroupReference} in this
     * thread group. Only the active thread groups in this immediate thread group
     * (and not its subgroups) are returned.
     * See <a href="{@docRoot}/../../../../api/java/lang/ThreadGroup.html">java.lang.ThreadGroup</a>
     * for information about 'active' ThreadGroups.
     * @return a List of {@link ThreadGroupReference} objects mirroring the
     * active thread groups from this thread group in the target VM.
     */
    List<ThreadGroupReference> threadGroups();
}