/* * Copyright (c) 2012, 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.management; import java.lang.management.PlatformManagedObject; import javax.management.DynamicMBean; /** * Diagnostic Commands interface for the HotSpot Virtual Machine. * *
The diagnostic command MBean is registered to the platform MBeanServer * as are other platform MBeans. * *
The ObjectName
for uniquely identifying the diagnostic
* MBean within an MBeanServer is:
*
* com.sun.management:type=DiagnosticCommand ** * It can be obtained by calling the * {@link PlatformManagedObject#getObjectName} method. * *
This MBean is an instance of DynamicMBean. Its content is generated at * runtime and is subject to modifications during the lifetime of the * Java virtual machine. * *
This MBean implements the DynamicMBean interface and * the NotificationEmitter interface. * *
The dynamically defined part of the DiagnosticCommandMBean * is made of a set of operations, one per diagnostic command * available through the JMX API. Diagnostic commands names often include * characters forbidden in Java method names (like dots). The generation of * an operation name for a given diagnostic command is implementation dependent. * The recommended way to transform diagnostic command name into a MBean * operation name is described below: *
Whatever algorithm is used to generated the operation name, the original * diagnostic command name is always provided with the meta-data on the * operation in a field named dcmd.name (see below). * *
All the operations associated with a diagnostic command return * a String. * *
All the operations associated with a diagnostic command which * doesn't support any option or argument have the following * signature: *
* ()Ljava/lang/String; **
All the operations associated with a diagnostic command supporting * at least one option or argument have the following signature: *
* ([Ljava/lang/String;)Ljava/lang/String; **
For these operations, all the options and arguments are passed into an * array of String. Each option or argument must be stored in a single String. * Options or arguments split across several String instances are not supported. * *
The distinction between options and arguments:options are identified by * the option name while arguments are identified by their position in the * command line. Options and arguments are processed in the order of the array * passed to the invocation method. * *
Like any operation of a dynamic MBean, each of these operations is * described by MBeanOperationInfo instance. Here's the values returned * by this object: *
ACTION_INFO
The Descriptor is a collection of fields containing additional * meta-data for a JMX element. A field is a name and an associated value. * The additional meta-data provided for an operation associated with a * diagnostic command are described in the table below: *
* *
Name | Type | Description | *
---|---|---|
dcmd.name | String | *The original diagnostic command name (not the operation name) | *
dcmd.description | String | *The diagnostic command description | *
dcmd.help | String | *The full help message for this diagnostic command (same output as * the one produced by the 'help' command) | *
dcmd.vmImpact | String | *The impact of the diagnostic command, * this value is the same as the one printed in the 'impact' * section of the help message of the diagnostic command, and it * is different from the getImpact() of the MBeanOperationInfo | *
dcmd.enabled | boolean | *True if the diagnostic command is enabled, false otherwise | *
dcmd.permissionClass | String | *Some diagnostic command might require a specific permission to be * executed, in addition to the MBeanPermission to invoke their * associated MBean operation. This field returns the class name * of this permission or null if no permission is required | *
dcmd.permissionName | String | *The fist argument of the permission required to execute this * diagnostic command or null if no permission is required | *
dcmd.permissionAction | String | *The second argument of the permission required to execute this * diagnostic command or null if the permission constructor has only * one argument (like the ManagementPermission) or if no permission * is required | *
dcmd.arguments | Descriptor | *A Descriptor instance containing the descriptions of options and * arguments supported by the diagnostic command (see below) | *
* *
The description of parameters (options or arguments) of a diagnostic * command is provided within a Descriptor instance. In this Descriptor, * each field name is a parameter name, and each field value is itself * a Descriptor instance. The fields provided in this second Descriptor * instance are described in the table below: * *
Name | Type | Description | *
---|---|---|
dcmd.arg.name | String | *The name of the parameter | *
dcmd.arg.type | String | *The type of the parameter. The returned String is the name of a type * recognized by the diagnostic command parser. These types are not * Java types and are implementation dependent. * | *
dcmd.arg.description | String | *The parameter description | *
dcmd.arg.isMandatory | boolean | *True if the parameter is mandatory, false otherwise | *
dcmd.arg.isOption | boolean | *True if the parameter is an option, false if it is an argument | *
dcmd.arg.isMultiple | boolean | *True if the parameter can be specified several times, false * otherwise | *
When the set of diagnostic commands currently supported by the Java
* Virtual Machine is modified, the DiagnosticCommandMBean
emits
* a {@link Notification} with a {@linkplain Notification#getType() type} of
* {@code "jmx.mbean.info.changed"} and a {@linkplain
* Notification#getUserData() userData} that is the new {@code MBeanInfo}.
*
* @since 7u12
*/
public interface DiagnosticCommandMBean extends DynamicMBean,
PlatformManagedObject {
}