HotSpotDiagnosticMXBean.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
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 * 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).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package com.sun.management;

import java.lang.management.PlatformManagedObject;

/**
 * Diagnostic management interface for the HotSpot Virtual Machine.
 *
 * <p>The diagnostic MBean is registered to the platform MBeanServer
 * as are other platform MBeans.
 *
 * <p>The <tt>ObjectName</tt> for uniquely identifying the diagnostic
 * MXBean within an MBeanServer is:
 * <blockquote>
 *    <tt>com.sun.management:type=HotSpotDiagnostic</tt>
 * </blockquote>
.*
 * It can be obtained by calling the
 * {@link PlatformManagedObject#getObjectName} method.
 *
 * All methods throw a {@code NullPointerException} if any input argument is
 * {@code null} unless it's stated otherwise.
 *
 * @see ManagementFactory#getPlatformMXBeans(Class)
 */
@jdk.Exported
public interface HotSpotDiagnosticMXBean extends PlatformManagedObject {
    /**
     * Dumps the heap to the <tt>outputFile</tt> file in the same
     * format as the hprof heap dump.
     * <p>
     * If this method is called remotely from another process,
     * the heap dump output is written to a file named <tt>outputFile</tt>
     * on the machine where the target VM is running.  If outputFile is
     * a relative path, it is relative to the working directory where
     * the target VM was started.
     *
     * @param  outputFile the system-dependent filename
     * @param  live if <tt>true</tt> dump only <i>live</i> objects
     *         i.e. objects that are reachable from others
     * @throws IOException if the <tt>outputFile</tt> already exists,
     *                     cannot be created, opened, or written to.
     * @throws UnsupportedOperationException if this operation is not supported.
     * @throws IllegalArgumentException if <tt>outputFile</tt> does not end with ".hprof" suffix.
     * @throws NullPointerException if <tt>outputFile</tt> is <tt>null</tt>.
     * @throws SecurityException
     *         If a security manager exists and its {@link
     *         java.lang.SecurityManager#checkWrite(java.lang.String)}
     *         method denies write access to the named file
     *         or the caller does not have ManagmentPermission("control").
     */
    public void dumpHeap(String outputFile, boolean live) throws java.io.IOException;

    /**
     * Returns a list of <tt>VMOption</tt> objects for all diagnostic options.
     * A diagnostic option is a {@link VMOption#isWriteable writeable}
     * VM option that can be set dynamically mainly for troubleshooting
     * and diagnosis.
     *
     * @return a list of <tt>VMOption</tt> objects for all diagnostic options.
     */
    public java.util.List<VMOption> getDiagnosticOptions();

    /**
     * Returns a <tt>VMOption</tt> object for a VM option of the given
     * name.
     *
     * @return a <tt>VMOption</tt> object for a VM option of the given name.
     * @throws NullPointerException if name is <tt>null</tt>.
     * @throws IllegalArgumentException if a VM option of the given name
     *                                     does not exist.
     */
    public VMOption getVMOption(String name);

    /**
     * Sets a VM option of the given name to the specified value.
     * The new value will be reflected in a new <tt>VMOption</tt>
     * object returned by the {@link #getVMOption} method or
     * the {@link #getDiagnosticOptions} method.  This method does
     * not change the value of this <tt>VMOption</tt> object.
     *
     * @param name Name of a VM option
     * @param value New value of the VM option to be set
     *
     * @throws IllegalArgumentException if the VM option of the given name
     *                                     does not exist.
     * @throws IllegalArgumentException if the new value is invalid.
     * @throws IllegalArgumentException if the VM option is not writable.
     * @throws NullPointerException if name or value is <tt>null</tt>.
     *
     * @throws  java.lang.SecurityException
     *     if a security manager exists and the caller does not have
     *     ManagementPermission("control").
     */
    public void setVMOption(String name, String value);
}