/* * Copyright (c) 1998, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.sun.jdi; import java.util.List; /** * 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.     *     * @return the string containing the thread group name.     */    String name();     /**     * 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 {@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 {@link ThreadReference#resume}.     * @throws VMCannotBeModifiedException if the VirtualMachine is read-only - see {@link VirtualMachine#canBeModified()}.     */    void resume();     /**     * 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 {@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();}