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         <p>Provides the core classes for the Java Management Extensions.</p>

         <p>The Java Management Extensions
             (JMX<sup><font size="-1">TM</font></sup>) API is a standard
         API for management and monitoring.  Typical uses include:</p>

         <ul>
             <li>consulting and changing application configuration</li>

             <li>accumulating statistics about application behavior and
             making them available</li>

             <li>notifying of state changes and erroneous conditions.</li>
         </ul>

         <p>The JMX API can also be used as part of a solution for
         managing systems, networks, and so on.</p>

         <p>The API includes remote access, so a remote management
             program can interact with a running application for these
         purposes.</p>

         <h2>MBeans</h2>

         <p>The fundamental notion of the JMX API is the <em>MBean</em>.
             An MBean is a named <em>managed object</em> representing a
             resource.  It has a <em id="mgIface">management interface</em>
             which must be <em>public</em> and consist of:</p>

         <ul>
             <li>named and typed attributes that can be read and/or
             written</li>

             <li>named and typed operations that can be invoked</li>

             <li>typed notifications that can be emitted by the MBean.</li>
         </ul>

         <p>For example, an MBean representing an application's
             configuration could have attributes representing the different
             configuration items.  Reading the <code>CacheSize</code>
             attribute would return the current value of that item.
             Writing it would update the item, potentially changing the
             behavior of the running application.  An operation such as
             <code>save</code> could store the current configuration
             persistently.  A notification such as
             <code>ConfigurationChangedNotification</code> could be sent
         every time the configuration is changed.</p>

         <p>In the standard usage of the JMX API, MBeans are implemented
             as Java objects.  However, as explained below, these objects are
         not usually referenced directly.</p>


         <h3>Standard MBeans</h3>

         <p>To make MBean implementation simple, the JMX API includes the
             notion of <em>Standard MBeans</em>.  A Standard MBean is one
             whose attributes and operations are deduced from a Java
             interface using certain naming patterns, similar to those used
             by JavaBeans<sup><font size="-1">TM</font></sup>.  For
         example, consider an interface like this:</p>

         <pre>
     public interface ConfigurationMBean {
          public int getCacheSize();
          public void setCacheSize(int size);
          public long getLastChangedTime();
          public void save();
     }
         </pre>

         <p>The methods <code>getCacheSize</code> and
             <code>setCacheSize</code> define a read-write attribute of
             type <code>int</code> called <code>CacheSize</code> (with an
         initial capital, unlike the JavaBeans convention).</p>

         <p>The method <code>getLastChangedTime</code> defines an
             attribute of type <code>long</code> called
             <code>LastChangedTime</code>.  This is a read-only attribute,
         since there is no method <code>setLastChangedTime</code>.</p>

         <p>The method <code>save</code> defines an operation called
             <code>save</code>.  It is not an attribute, since its name
             does not begin with <code>get</code>, <code>set</code>, or
         <code>is</code>.</p>

         <p>The exact naming patterns for Standard MBeans are detailed in
         the <a href="#spec">JMX Specification</a>.</p>

         <p>There are two ways to make a Java object that is an MBean
             with this management interface.  One is for the object to be
             of a class that has exactly the same name as the Java
             interface but without the <code>MBean</code> suffix.  So in
             the example the object would be of the class
             <code>Configuration</code>, in the same Java package as
             <code>ConfigurationMBean</code>.  The second way is to use the
             {@link javax.management.StandardMBean StandardMBean}
         class.</p>


         <h3>MXBeans</h3>

         <p>An <em>MXBean</em> is a variant of Standard MBean where complex
             types are mapped to a standard set of types defined in the
             {@link javax.management.openmbean} package.  MXBeans are appropriate
             if you would otherwise need to reference application-specific
             classes in your MBean interface.  They are described in detail
         in the specification for {@link javax.management.MXBean MXBean}.</p>


         <h3>Dynamic MBeans</h3>

         <p>A <em>Dynamic MBean</em> is an MBean that defines its
             management interface at run-time.  For example, a configuration
             MBean could determine the names and types of the attributes it
         exposes by parsing an XML file.</p>

         <p>Any Java object of a class that implements the {@link
             javax.management.DynamicMBean DynamicMBean} interface is a
         Dynamic MBean.</p>


         <h3>Open MBeans</h3>

         <p>An <em>Open MBean</em> is a kind of Dynamic MBean where the
             types of attributes and of operation parameters and return
             values are built using a small set of predefined Java classes.
             Open MBeans facilitate operation with remote management programs
             that do not necessarily have access to application-specific
             types, including non-Java programs.  Open MBeans are defined by
             the package <a href="openmbean/package-summary.html"><code>
         javax.management.openmbean</code></a>.</p>


         <h3>Model MBeans</h3>

         <p>A <em>Model MBean</em> is a kind of Dynamic MBean that acts
             as a bridge between the management interface and the
             underlying managed resource.  Both the management interface and
             the managed resource are specified as Java objects.  The same
             Model MBean implementation can be reused many times with
             different management interfaces and managed resources, and it can
             provide common functionality such as persistence and caching.
             Model MBeans are defined by the package
             <a href="modelmbean/package-summary.html"><code>
         javax.management.modelmbean</code></a>.</p>


         <h2>MBean Server</h2>

         <p>To be useful, an MBean must be registered in an <em>MBean
             Server</em>.  An MBean Server is a repository of MBeans.
             Usually the only access to the MBeans is through the MBean
             Server.  In other words, code no longer accesses the Java
             object implementing the MBean directly, but instead accesses
             the MBean by name through the MBean Server.  Each MBean has a
             unique name within the MBean Server, defined by the {@link
         javax.management.ObjectName ObjectName} class.</p>

         <p>An MBean Server is an object implementing the interface
             {@link javax.management.MBeanServer MBeanServer}.
             The most convenient MBean Server to use is the
             <em>Platform MBean Server</em>.  This is a
             single MBean Server that can be shared by different managed
             components running within the same Java Virtual Machine.  The
             Platform MBean Server is accessed with the method {@link
         java.lang.management.ManagementFactory#getPlatformMBeanServer()}.</p>

         <p>Application code can also create a new MBean Server, or
             access already-created MBean Servers, using the {@link
         javax.management.MBeanServerFactory MBeanServerFactory} class.</p>


         <h3>Creating MBeans in the MBean Server</h3>

         <p>There are two ways to create an MBean.  One is to construct a
             Java object that will be the MBean, then use the {@link
             javax.management.MBeanServer#registerMBean registerMBean}
             method to register it in the MBean Server.  The other is to
             create and register the MBean in a single operation using one
             of the {@link javax.management.MBeanServer#createMBean(String,
         javax.management.ObjectName) createMBean} methods.</p>

         <p>The <code>registerMBean</code> method is simpler for local
             use, but cannot be used remotely.  The
             <code>createMBean</code> method can be used remotely, but
         sometimes requires attention to class loading issues.</p>

         <p>An MBean can perform actions when it is registered in or
             unregistered from an MBean Server if it implements the {@link
             javax.management.MBeanRegistration MBeanRegistration}
         interface.</p>


         <h3>Accessing MBeans in the MBean Server</h3>

         <p>Given an <code>ObjectName</code> <code>name</code> and an
             <code>MBeanServer</code> <code>mbs</code>, you can access
         attributes and operations as in this example:</p>

         <pre>
     int cacheSize = mbs.getAttribute(name, "CacheSize");
     {@link javax.management.Attribute Attribute} newCacheSize =
          new Attribute("CacheSize", new Integer(2000));
     mbs.setAttribute(name, newCacheSize);
     mbs.invoke(name, "save", new Object[0], new Class[0]);
         </pre>

         <p id="proxy">Alternatively, if you have a Java interface that
             corresponds to the management interface for the MBean, you can use an
         <em>MBean proxy</em> like this:</p>

         <pre>
     ConfigurationMBean conf =
         {@link javax.management.JMX#newMBeanProxy
             JMX.newMBeanProxy}(mbs, name, ConfigurationMBean.class);
     int cacheSize = conf.getCacheSize();
     conf.setCacheSize(2000);
     conf.save();
         </pre>

         <p>Using an MBean proxy is just a convenience.  The second
             example ends up calling the same <code>MBeanServer</code>
         operations as the first one.</p>

         <p>An MBean Server can be queried for MBeans whose names match
             certain patterns and/or whose attributes meet certain
             constraints.  Name patterns are constructed using the {@link
             javax.management.ObjectName ObjectName} class and constraints
             are constructed using the {@link javax.management.Query Query}
             class.  The methods {@link
             javax.management.MBeanServer#queryNames queryNames} and {@link
             javax.management.MBeanServer#queryMBeans queryMBeans} then
         perform the query.</p>


         <h3>MBean lifecycle</h3>

         <p>An MBean can implement the {@link javax.management.MBeanRegistration
             MBeanRegistration} interface in order to be told when it is registered
             and unregistered in the MBean Server. Additionally, the {@link
             javax.management.MBeanRegistration#preRegister preRegister} method
             allows the MBean to get a reference to the <code>MBeanServer</code>
             object and to get its <code>ObjectName</code> within the MBean
         Server.</p>


         <h2>Notifications</h2>

         <p>A <em>notification</em> is an instance of the {@link
             javax.management.Notification Notification} class or a
             subclass.  In addition to its Java class, it has a
             <em>type</em> string that can distinguish it from other
         notifications of the same class.</p>

         <p>An MBean that will emit notifications must implement the
             {@link javax.management.NotificationBroadcaster
             NotificationBroadcaster} or {@link
             javax.management.NotificationEmitter NotificationEmitter}
             interface.  Usually, it does this by subclassing
             {@link javax.management.NotificationBroadcasterSupport
             NotificationBroadcasterSupport} or delegating to an instance of
         that class. Here is an example:</p>

         <pre>
     public class Configuration <b>extends NotificationBroadcasterSupport</b>
             implements ConfigurationMBean {
         ...
         private void updated() {
             Notification n = new Notification(...);
             <b>{@link javax.management.NotificationBroadcasterSupport#sendNotification
             sendNotification}(n)</b>;
         }
     }
         </pre>


         <p>Notifications can be received by a <em>listener</em>, which
             is an object that implements the {@link
             javax.management.NotificationListener NotificationListener}
             interface.  You can add a listener to an MBean with the method
             {@link
             javax.management.MBeanServer#addNotificationListener(ObjectName,
             NotificationListener, NotificationFilter, Object)}.
             You can optionally supply a <em>filter</em> to this method, to
             select only notifications of interest.  A filter is an object
             that implements the {@link javax.management.NotificationFilter
         NotificationFilter} interface.</p>

         <p>An MBean can be a listener for notifications emitted by other
             MBeans in the same MBean Server.  In this case, it implements
             {@link javax.management.NotificationListener
             NotificationListener} and the method {@link
             javax.management.MBeanServer#addNotificationListener(ObjectName,
         ObjectName, NotificationFilter, Object)} is used to listen.</p>


         <h2>Remote Access to MBeans</h2>

         <p>An MBean Server can be accessed remotely through a
             <em>connector</em>.  A connector allows a remote Java
             application to access an MBean Server in essentially the same
             way as a local one.  The package
             <a href="remote/package-summary.html"><code>
         javax.management.remote</code></a> defines connectors.</p>

         <p>The JMX specification also defines the notion of an
             <em>adaptor</em>.  An adaptor translates between requests in a
             protocol such as SNMP or HTML and accesses to an MBean Server.
             So for example an SNMP GET operation might result in a
         <code>getAttribute</code> on the MBean Server.</p>

 	<h3 id="interop">Interoperability between versions of the JMX
 	  specification</h3>

         <p>When a client connects to a server using the JMX Remote
             API, it is possible that they do not have the same version
             of the JMX specification.  The version of the JMX
             specification described here is version 1.4.  Previous
             versions were 1.0, 1.1, and 1.2.  (There was no 1.3.)
             The standard JMX Remote API is defined to work with version
             1.2 onwards, so in standards-based deployment the only
             interoperability questions that arise concern version 1.2
         onwards.</p>

         <p>Every version of the JMX specification continues to
             implement the features of previous versions.  So when the
             client is running an earlier version than the server, there
             should not be any interoperability concerns.</p>

         <p>When the client is running a later version than the server,
             certain newer features may not be available, as detailed in
             the next sections.  The client can determine the server's
             version by examining the {@link
             javax.management.MBeanServerDelegateMBean#getSpecificationVersion
             SpecificationVersion} attribute of the {@code
         MBeanServerDelegate}.</p>

         <h4 id="interop-1.2">If the remote MBean Server is 1.2</h4>

 	<ul>

             <li><p>You cannot use wildcards in a key property of an
                 {@link javax.management.ObjectName ObjectName}, for
                 example {@code domain:type=Foo,name=*}. Wildcards that
                 match whole properties are still allowed, for example
             {@code *:*} or {@code *:type=Foo,*}.</p>

             <li><p>You cannot use {@link
                 javax.management.Query#isInstanceOf Query.isInstanceOf}
             in a query.</p>

             <li><p>You cannot use dot syntax such as {@code
                 HeapMemoryUsage.used} in the {@linkplain
                 javax.management.monitor.Monitor#setObservedAttribute
                 observed attribute} of a monitor, as described in the
                 documentation for the {@link javax.management.monitor}
             package.</p>

         </ul>

         <p id="spec">
         @see <a href="{@docRoot}/../technotes/guides/jmx/index.html">
         Java Platform documentation on JMX technology</a>
         in particular the
         <a href="{@docRoot}/../technotes/guides/jmx/JMX_1_4_specification.pdf">
         JMX Specification, version 1.4(pdf).</a>

         @since 1.5

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	<p>Provides the core classes for the Java Management Extensions.</p>

	<p>The Java Management Extensions
	(JMX<sup><font size="-1">TM</font></sup>) API is a standard
	API for management and monitoring. Typical uses include:</p>

	<ul>
	<li>consulting and changing application configuration</li>

	<li>accumulating statistics about application behavior and
	making them available</li>

	<li>notifying of state changes and erroneous conditions.</li>
	</ul>

	<p>The JMX API can also be used as part of a solution for
	managing systems, networks, and so on.</p>

	<p>The API includes remote access, so a remote management
	program can interact with a running application for these
	purposes.</p>

	<h2>MBeans</h2>

	<p>The fundamental notion of the JMX API is the <em>MBean</em>.
	An MBean is a named <em>managed object</em> representing a
	resource. It has a <em id="mgIface">management interface</em>
	which must be <em>public</em> and consist of:</p>

	<ul>
	<li>named and typed attributes that can be read and/or
	written</li>

	<li>named and typed operations that can be invoked</li>

	<li>typed notifications that can be emitted by the MBean.</li>
	</ul>

	<p>For example, an MBean representing an application's
	configuration could have attributes representing the different
	configuration items. Reading the <code>CacheSize</code>
	attribute would return the current value of that item.
	Writing it would update the item, potentially changing the
	behavior of the running application. An operation such as
	<code>save</code> could store the current configuration
	persistently. A notification such as
	<code>ConfigurationChangedNotification</code> could be sent
	every time the configuration is changed.</p>

	<p>In the standard usage of the JMX API, MBeans are implemented
	as Java objects. However, as explained below, these objects are
	not usually referenced directly.</p>


	<h3>Standard MBeans</h3>

	<p>To make MBean implementation simple, the JMX API includes the
	notion of <em>Standard MBeans</em>. A Standard MBean is one
	whose attributes and operations are deduced from a Java
	interface using certain naming patterns, similar to those used
	by JavaBeans<sup><font size="-1">TM</font></sup>. For
	example, consider an interface like this:</p>

	<pre>
	public interface ConfigurationMBean {
	public int getCacheSize();
	public void setCacheSize(int size);
	public long getLastChangedTime();
	public void save();
	}
	</pre>

	<p>The methods <code>getCacheSize</code> and
	<code>setCacheSize</code> define a read-write attribute of
	type <code>int</code> called <code>CacheSize</code> (with an
	initial capital, unlike the JavaBeans convention).</p>

	<p>The method <code>getLastChangedTime</code> defines an
	attribute of type <code>long</code> called
	<code>LastChangedTime</code>. This is a read-only attribute,
	since there is no method <code>setLastChangedTime</code>.</p>

	<p>The method <code>save</code> defines an operation called
	<code>save</code>. It is not an attribute, since its name
	does not begin with <code>get</code>, <code>set</code>, or
	<code>is</code>.</p>

	<p>The exact naming patterns for Standard MBeans are detailed in
	the <a href="#spec">JMX Specification</a>.</p>

	<p>There are two ways to make a Java object that is an MBean
	with this management interface. One is for the object to be
	of a class that has exactly the same name as the Java
	interface but without the <code>MBean</code> suffix. So in
	the example the object would be of the class
	<code>Configuration</code>, in the same Java package as
	<code>ConfigurationMBean</code>. The second way is to use the
	{@link javax.management.StandardMBean StandardMBean}
	class.</p>


	<h3>MXBeans</h3>

	<p>An <em>MXBean</em> is a variant of Standard MBean where complex
	types are mapped to a standard set of types defined in the
	{@link javax.management.openmbean} package. MXBeans are appropriate
	if you would otherwise need to reference application-specific
	classes in your MBean interface. They are described in detail
	in the specification for {@link javax.management.MXBean MXBean}.</p>


	<h3>Dynamic MBeans</h3>

	<p>A <em>Dynamic MBean</em> is an MBean that defines its
	management interface at run-time. For example, a configuration
	MBean could determine the names and types of the attributes it
	exposes by parsing an XML file.</p>

	<p>Any Java object of a class that implements the {@link
	javax.management.DynamicMBean DynamicMBean} interface is a
	Dynamic MBean.</p>


	<h3>Open MBeans</h3>

	<p>An <em>Open MBean</em> is a kind of Dynamic MBean where the
	types of attributes and of operation parameters and return
	values are built using a small set of predefined Java classes.
	Open MBeans facilitate operation with remote management programs
	that do not necessarily have access to application-specific
	types, including non-Java programs. Open MBeans are defined by
	the package <a href="openmbean/package-summary.html"><code>
	javax.management.openmbean</code></a>.</p>


	<h3>Model MBeans</h3>

	<p>A <em>Model MBean</em> is a kind of Dynamic MBean that acts
	as a bridge between the management interface and the
	underlying managed resource. Both the management interface and
	the managed resource are specified as Java objects. The same
	Model MBean implementation can be reused many times with
	different management interfaces and managed resources, and it can
	provide common functionality such as persistence and caching.
	Model MBeans are defined by the package
	<a href="modelmbean/package-summary.html"><code>
	javax.management.modelmbean</code></a>.</p>


	<h2>MBean Server</h2>

	<p>To be useful, an MBean must be registered in an <em>MBean
	Server</em>. An MBean Server is a repository of MBeans.
	Usually the only access to the MBeans is through the MBean
	Server. In other words, code no longer accesses the Java
	object implementing the MBean directly, but instead accesses
	the MBean by name through the MBean Server. Each MBean has a
	unique name within the MBean Server, defined by the {@link
	javax.management.ObjectName ObjectName} class.</p>

	<p>An MBean Server is an object implementing the interface
	{@link javax.management.MBeanServer MBeanServer}.
	The most convenient MBean Server to use is the
	<em>Platform MBean Server</em>. This is a
	single MBean Server that can be shared by different managed
	components running within the same Java Virtual Machine. The
	Platform MBean Server is accessed with the method {@link
	java.lang.management.ManagementFactory#getPlatformMBeanServer()}.</p>

	<p>Application code can also create a new MBean Server, or
	access already-created MBean Servers, using the {@link
	javax.management.MBeanServerFactory MBeanServerFactory} class.</p>


	<h3>Creating MBeans in the MBean Server</h3>

	<p>There are two ways to create an MBean. One is to construct a
	Java object that will be the MBean, then use the {@link
	javax.management.MBeanServer#registerMBean registerMBean}
	method to register it in the MBean Server. The other is to
	create and register the MBean in a single operation using one
	of the {@link javax.management.MBeanServer#createMBean(String,
	javax.management.ObjectName) createMBean} methods.</p>

	<p>The <code>registerMBean</code> method is simpler for local
	use, but cannot be used remotely. The
	<code>createMBean</code> method can be used remotely, but
	sometimes requires attention to class loading issues.</p>

	<p>An MBean can perform actions when it is registered in or
	unregistered from an MBean Server if it implements the {@link
	javax.management.MBeanRegistration MBeanRegistration}
	interface.</p>


	<h3>Accessing MBeans in the MBean Server</h3>

	<p>Given an <code>ObjectName</code> <code>name</code> and an
	<code>MBeanServer</code> <code>mbs</code>, you can access
	attributes and operations as in this example:</p>

	<pre>
	int cacheSize = mbs.getAttribute(name, "CacheSize");
	{@link javax.management.Attribute Attribute} newCacheSize =
	new Attribute("CacheSize", new Integer(2000));
	mbs.setAttribute(name, newCacheSize);
	mbs.invoke(name, "save", new Object[0], new Class[0]);
	</pre>

	<p id="proxy">Alternatively, if you have a Java interface that
	corresponds to the management interface for the MBean, you can use an
	<em>MBean proxy</em> like this:</p>

	<pre>
	ConfigurationMBean conf =
	{@link javax.management.JMX#newMBeanProxy
	JMX.newMBeanProxy}(mbs, name, ConfigurationMBean.class);
	int cacheSize = conf.getCacheSize();
	conf.setCacheSize(2000);
	conf.save();
	</pre>

	<p>Using an MBean proxy is just a convenience. The second
	example ends up calling the same <code>MBeanServer</code>
	operations as the first one.</p>

	<p>An MBean Server can be queried for MBeans whose names match
	certain patterns and/or whose attributes meet certain
	constraints. Name patterns are constructed using the {@link
	javax.management.ObjectName ObjectName} class and constraints
	are constructed using the {@link javax.management.Query Query}
	class. The methods {@link
	javax.management.MBeanServer#queryNames queryNames} and {@link
	javax.management.MBeanServer#queryMBeans queryMBeans} then
	perform the query.</p>


	<h3>MBean lifecycle</h3>

	<p>An MBean can implement the {@link javax.management.MBeanRegistration
	MBeanRegistration} interface in order to be told when it is registered
	and unregistered in the MBean Server. Additionally, the {@link
	javax.management.MBeanRegistration#preRegister preRegister} method
	allows the MBean to get a reference to the <code>MBeanServer</code>
	object and to get its <code>ObjectName</code> within the MBean
	Server.</p>


	<h2>Notifications</h2>

	<p>A <em>notification</em> is an instance of the {@link
	javax.management.Notification Notification} class or a
	subclass. In addition to its Java class, it has a
	<em>type</em> string that can distinguish it from other
	notifications of the same class.</p>

	<p>An MBean that will emit notifications must implement the
	{@link javax.management.NotificationBroadcaster
	NotificationBroadcaster} or {@link
	javax.management.NotificationEmitter NotificationEmitter}
	interface. Usually, it does this by subclassing
	{@link javax.management.NotificationBroadcasterSupport
	NotificationBroadcasterSupport} or delegating to an instance of
	that class. Here is an example:</p>

	<pre>
	public class Configuration <b>extends NotificationBroadcasterSupport</b>
	implements ConfigurationMBean {
	...
	private void updated() {
	Notification n = new Notification(...);
	<b>{@link javax.management.NotificationBroadcasterSupport#sendNotification
	sendNotification}(n)</b>;
	}
	}
	</pre>


	<p>Notifications can be received by a <em>listener</em>, which
	is an object that implements the {@link
	javax.management.NotificationListener NotificationListener}
	interface. You can add a listener to an MBean with the method
	{@link
	javax.management.MBeanServer#addNotificationListener(ObjectName,
	NotificationListener, NotificationFilter, Object)}.
	You can optionally supply a <em>filter</em> to this method, to
	select only notifications of interest. A filter is an object
	that implements the {@link javax.management.NotificationFilter
	NotificationFilter} interface.</p>

	<p>An MBean can be a listener for notifications emitted by other
	MBeans in the same MBean Server. In this case, it implements
	{@link javax.management.NotificationListener
	NotificationListener} and the method {@link
	javax.management.MBeanServer#addNotificationListener(ObjectName,
	ObjectName, NotificationFilter, Object)} is used to listen.</p>


	<h2>Remote Access to MBeans</h2>

	<p>An MBean Server can be accessed remotely through a
	<em>connector</em>. A connector allows a remote Java
	application to access an MBean Server in essentially the same
	way as a local one. The package
	<a href="remote/package-summary.html"><code>
	javax.management.remote</code></a> defines connectors.</p>

	<p>The JMX specification also defines the notion of an
	<em>adaptor</em>. An adaptor translates between requests in a
	protocol such as SNMP or HTML and accesses to an MBean Server.
	So for example an SNMP GET operation might result in a
	<code>getAttribute</code> on the MBean Server.</p>

	<h3 id="interop">Interoperability between versions of the JMX
	specification</h3>

	<p>When a client connects to a server using the JMX Remote
	API, it is possible that they do not have the same version
	of the JMX specification. The version of the JMX
	specification described here is version 1.4. Previous
	versions were 1.0, 1.1, and 1.2. (There was no 1.3.)
	The standard JMX Remote API is defined to work with version
	1.2 onwards, so in standards-based deployment the only
	interoperability questions that arise concern version 1.2
	onwards.</p>

	<p>Every version of the JMX specification continues to
	implement the features of previous versions. So when the
	client is running an earlier version than the server, there
	should not be any interoperability concerns.</p>

	<p>When the client is running a later version than the server,
	certain newer features may not be available, as detailed in
	the next sections. The client can determine the server's
	version by examining the {@link
	javax.management.MBeanServerDelegateMBean#getSpecificationVersion
	SpecificationVersion} attribute of the {@code
	MBeanServerDelegate}.</p>

	<h4 id="interop-1.2">If the remote MBean Server is 1.2</h4>

	<ul>

	<li><p>You cannot use wildcards in a key property of an
	{@link javax.management.ObjectName ObjectName}, for
	example {@code domain:type=Foo,name=*}. Wildcards that
	match whole properties are still allowed, for example
	{@code :} or {@code :type=Foo,}.</p>

	<li><p>You cannot use {@link
	javax.management.Query#isInstanceOf Query.isInstanceOf}
	in a query.</p>

	<li><p>You cannot use dot syntax such as {@code
	HeapMemoryUsage.used} in the {@linkplain
	javax.management.monitor.Monitor#setObservedAttribute
	observed attribute} of a monitor, as described in the
	documentation for the {@link javax.management.monitor}
	package.</p>

	</ul>

	<p id="spec">
	@see <a href="{@docRoot}/../technotes/guides/jmx/index.html">
	Java Platform documentation on JMX technology</a>
	in particular the
	<a href="{@docRoot}/../technotes/guides/jmx/JMX_1_4_specification.pdf">
	JMX Specification, version 1.4(pdf).</a>

	@since 1.5

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