1 /* MBeanServerFactory.java -- Manages server instances.
2 Copyright (C) 2006 Free Software Foundation, Inc.
4 This file is part of GNU Classpath.
6 GNU Classpath is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU Classpath is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU Classpath; see the file COPYING. If not, write to the
18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
21 Linking this library statically or dynamically with other modules is
22 making a combined work based on this library. Thus, the terms and
23 conditions of the GNU General Public License cover the whole
26 As a special exception, the copyright holders of this library give you
27 permission to link this library with independent modules to produce an
28 executable, regardless of the license terms of these independent
29 modules, and to copy and distribute the resulting executable under
30 terms of your choice, provided that you also meet, for each linked
31 independent module, the terms and conditions of the license of that
32 module. An independent module is a module which is not derived from
33 or based on this library. If you modify this library, you may extend
34 this exception to your version of the library, but you are not
35 obligated to do so. If you do not wish to do so, delete this
36 exception statement from your version. */
38 package javax
.management
;
40 import gnu
.classpath
.SystemProperties
;
42 import java
.util
.ArrayList
;
43 import java
.util
.HashMap
;
44 import java
.util
.Iterator
;
47 import javax
.management
.loading
.ClassLoaderRepository
;
51 * Creates and maintains a set of {@link MBeanServer} instances.
52 * Server instances, as of JMX 1.2, are created using a subclass
53 * of {@link MBeanServerBuilder}. The exact class used is controlled
54 * by the property <code>javax.management.builder.initial</code>,
55 * and allows the instances created by {@link MBeanServerBuilder}
56 * to be wrapped, thus providing additional functionality.
59 * The property is used as follows:
62 * <li>If the property has no value, then an instance of
63 * {@link MBeanServerBuilder} is used.</li>
64 * <li>If a value is given, then:
66 * <li>The class is loaded using
67 * <code>Thread.currentThread().getContextClassLoader()</code>, or,
68 * if this is <code>null</code>, by <code>Class.forName()</code>.</li>
69 * <li><code>Class.newInstance()</code> is used to create an instance
70 * of the class. The class must be public and have a public empty
71 * constructor. If an exception is thrown, it is propogated as
72 * a {@link JMRuntimeException} and no new server instances may be
73 * created until the property is set to a valid value.</li>
75 * <li>The value is checked on each successive request for a server.
76 * If it differs from the class of the existing instance of
77 * {@link MBeanServerBuilder}, then the value is used to create
78 * a new instance.</li>
81 public class MBeanServerFactory
85 * The last builder instance.
87 private static MBeanServerBuilder builder
;
90 * The map of registered servers (identifiers to servers).
92 private static final Map
<Object
,MBeanServer
> servers
=
93 new HashMap
<Object
,MBeanServer
>();
96 * Private constructor to prevent instance creation.
98 private MBeanServerFactory() {}
101 * Returns a server implementation using the default domain name
102 * of <code>"DefaultDomain"</code>. The default domain name is
103 * used when the domain name specified by the user is <code>null</code.
104 * A reference to the created server is retained, so that it can
105 * be retrieved at a later date using {@link #findMBeanServer}.
106 * Calling this method is equivalent to calling
107 * {@link createMBeanServer(String)} with a <code>null</code> value.
109 * @return a new {@link MBeanServer} instance.
110 * @throws SecurityException if a security manager exists and the
111 * caller's permissions don't imply {@link
112 * MBeanServerPermission(String)}("createMBeanServer")
113 * @throws JMRuntimeException if the property
114 * <code>javax.management.builder.initial</code>
115 * exists but names a class which either can not be
116 * instantiated or provides an implementation that returns
117 * <code>null</code> from either
118 * {@link MBeanServerBuilder#newMBeanServerDelegate()}
119 * or {@link MBeanServerBuilder#newMBeanServer()}
120 * @throws ClassCastException if the property
121 * <code>javax.management.builder.initial</code>
122 * exists but names a class which is not a subclass
123 * of {@link MBeanServerBuilder}.
124 * @see #createMBeanServer(String)
126 public static MBeanServer
createMBeanServer()
128 return createMBeanServer(null);
132 * Returns a server implementation using the default domain name
133 * given, or <code>"DefaultDomain"</code> if this is <code>null</code>.
134 * The default domain name is used when the domain name specified by
135 * the user is <code>null</code. A reference to the created server is
136 * retained, so that it can be retrieved at a later date using
137 * {@link #findMBeanServer}.
139 * @param domain the default domain name of the server.
140 * @return a new {@link MBeanServer} instance.
141 * @throws SecurityException if a security manager exists and the
142 * caller's permissions don't imply {@link
143 * MBeanServerPermission(String)}("createMBeanServer")
144 * @throws JMRuntimeException if the property
145 * <code>javax.management.builder.initial</code>
146 * exists but names a class which either can not be
147 * instantiated or provides an implementation that returns
148 * <code>null</code> from either
149 * {@link MBeanServerBuilder#newMBeanServerDelegate()}
150 * or {@link MBeanServerBuilder#newMBeanServer()}
151 * @throws ClassCastException if the property
152 * <code>javax.management.builder.initial</code>
153 * exists but names a class which is not a subclass
154 * of {@link MBeanServerBuilder}.
156 public static MBeanServer
createMBeanServer(String domain
)
158 SecurityManager sm
= System
.getSecurityManager();
160 sm
.checkPermission(new MBeanServerPermission("createMBeanServer"));
161 MBeanServer server
= createServer(domain
);
165 ObjectName("JMImplementation:type=MBeanServerDelegate");
166 servers
.put(server
.getAttribute(dn
, "MBeanServerId"), server
);
168 catch (MalformedObjectNameException e
)
171 (new InternalError("Malformed delegate bean name.").initCause(e
));
173 catch (MBeanException e
)
176 (new InternalError("Exception in getMBeanServerId().").initCause(e
));
178 catch (AttributeNotFoundException e
)
181 (new InternalError("Could not find MBeanServerId attribute.").initCause(e
));
183 catch (InstanceNotFoundException e
)
186 (new InternalError("Could not find the delegate bean.").initCause(e
));
188 catch (ReflectionException e
)
191 (new InternalError("Could not call getMBeanServerId().").initCause(e
));
197 * Returns the specified server, or, if <code>id</code> is <code>null</code>,
198 * a list of all registered servers. A registered server is one that
199 * was created using {@link #createMBeanServer()} or
200 * {@link #createMBeanServer(String)} and has not yet been released
201 * using {@link releaseMBeanServer(MBeanServer)}.
203 * @param id the id of the server to retrieve, or <code>null</code>
204 * to return all servers.
205 * @return a list of {@link MBeanServer}s.
206 * @throws SecurityException if a security manager exists and the
207 * caller's permissions don't imply {@link
208 * MBeanServerPermission(String)}("findMBeanServer")
210 public static ArrayList
<MBeanServer
> findMBeanServer(String id
)
212 SecurityManager sm
= System
.getSecurityManager();
214 sm
.checkPermission(new MBeanServerPermission("findMBeanServer"));
216 return new ArrayList
<MBeanServer
>(servers
.values());
217 ArrayList
<MBeanServer
> list
= new ArrayList
<MBeanServer
>();
218 MBeanServer server
= servers
.get(id
);
220 list
.add(servers
.get(id
));
225 * Returns the class loader repository used by the specified server.
226 * This is equivalent to calling {@link MBeanServer#getClassLoaderRepository()}
227 * on the given server.
229 * @param server the server whose class loader repository should be
231 * @throws NullPointerException if <code>server</code> is <code>null</code>.
232 * @throws SecurityException if a security manager exists and the
233 * caller's permissions don't imply {@link
234 * MBeanPermission(String,String,ObjectName,String)
235 * <code>MBeanPermission(null, null, null,
236 * "getClassLoaderRepository")</code>
238 public static ClassLoaderRepository
getClassLoaderRepository(MBeanServer server
)
240 return server
.getClassLoaderRepository();
244 * Returns a server implementation using the default domain name
245 * of <code>"DefaultDomain"</code>. The default domain name is
246 * used when the domain name specified by the user is <code>null</code.
247 * No reference to the created server is retained, so the server is
248 * garbage collected when it is no longer used, but it can not be
249 * retrieved at a later date using {@link #findMBeanServer}.
250 * Calling this method is equivalent to calling
251 * {@link newMBeanServer(String)} with a <code>null</code> value.
253 * @return a new {@link MBeanServer} instance.
254 * @throws SecurityException if a security manager exists and the
255 * caller's permissions don't imply {@link
256 * MBeanServerPermission(String)}("newMBeanServer")
257 * @throws JMRuntimeException if the property
258 * <code>javax.management.builder.initial</code>
259 * exists but names a class which either can not be
260 * instantiated or provides an implementation that returns
261 * <code>null</code> from either
262 * {@link MBeanServerBuilder#newMBeanServerDelegate()}
263 * or {@link MBeanServerBuilder#newMBeanServer()}
264 * @throws ClassCastException if the property
265 * <code>javax.management.builder.initial</code>
266 * exists but names a class which is not a subclass
267 * of {@link MBeanServerBuilder}.
268 * @see #newMBeanServer(String)
270 public static MBeanServer
newMBeanServer()
272 return newMBeanServer(null);
276 * Returns a server implementation using the default domain name
277 * given, or <code>"DefaultDomain"</code> if this is <code>null</code>.
278 * The default domain name is used when the domain name specified by
279 * the user is <code>null</code. No reference to the created server is
280 * retained, so the server is garbage collected when it is no longer
281 * used, but it can not be retrieved at a later date using
282 * {@link #findMBeanServer}.
284 * @param domain the default domain name of the server.
285 * @return a new {@link MBeanServer} instance.
286 * @throws SecurityException if a security manager exists and the
287 * caller's permissions don't imply {@link
288 * MBeanServerPermission(String)}("newMBeanServer")
289 * @throws JMRuntimeException if the property
290 * <code>javax.management.builder.initial</code>
291 * exists but names a class which either can not be
292 * instantiated or provides an implementation that returns
293 * <code>null</code> from either
294 * {@link MBeanServerBuilder#newMBeanServerDelegate()}
295 * or {@link MBeanServerBuilder#newMBeanServer()}
296 * @throws ClassCastException if the property
297 * <code>javax.management.builder.initial</code>
298 * exists but names a class which is not a subclass
299 * of {@link MBeanServerBuilder}.
301 public static MBeanServer
newMBeanServer(String domain
)
303 SecurityManager sm
= System
.getSecurityManager();
305 sm
.checkPermission(new MBeanServerPermission("newMBeanServer"));
306 return createServer(domain
);
310 * Common method to create a server for the {@link #createMBeanServer(String)}
311 * and {@link #newMBeanServer(String)} methods above.
313 * @param domain the default domain name of the server.
314 * @throws JMRuntimeException if the property
315 * <code>javax.management.builder.initial</code>
316 * exists but names a class which either can not be
317 * instantiated or provides an implementation that returns
318 * <code>null</code> from either
319 * {@link MBeanServerBuilder#newMBeanServerDelegate()}
320 * or {@link MBeanServerBuilder#newMBeanServer()}
321 * @throws ClassCastException if the property
322 * <code>javax.management.builder.initial</code>
323 * exists but names a class which is not a subclass
324 * of {@link MBeanServerBuilder}.
326 private static MBeanServer
createServer(String domain
)
329 domain
= "DefaultDomain";
330 String builderClass
=
331 SystemProperties
.getProperty("javax.management.builder.initial");
332 if (builderClass
== null)
334 if (builder
== null ||
335 builder
.getClass() != MBeanServerBuilder
.class)
336 builder
= new MBeanServerBuilder();
338 else if (!(builder
!= null &&
339 builderClass
.equals(builder
.getClass().getName())))
341 ClassLoader cl
= Thread
.currentThread().getContextClassLoader();
343 cl
= MBeanServerFactory
.class.getClassLoader();
346 Class
<?
> bClass
= Class
.forName(builderClass
, true, cl
);
347 builder
= (MBeanServerBuilder
) bClass
.newInstance();
349 catch (ClassNotFoundException e
)
351 throw (JMRuntimeException
) (new JMRuntimeException("The builder class, "
353 ", could not be found."))
356 catch (InstantiationException e
)
358 throw (JMRuntimeException
) (new JMRuntimeException("The builder class, "
360 ", could not be instantiated."))
363 catch (IllegalAccessException e
)
365 throw (JMRuntimeException
) (new JMRuntimeException("The builder class, "
367 ", could not be accessed."))
371 MBeanServerDelegate delegate
= builder
.newMBeanServerDelegate();
372 if (delegate
== null)
373 throw new JMRuntimeException("A delegate could not be created.");
374 MBeanServer server
= builder
.newMBeanServer(domain
, null, delegate
);
376 throw new JMRuntimeException("A server could not be created.");
381 * Removes the reference to the specified server, thus allowing it to
382 * be garbage collected.
384 * @param server the server to remove.
385 * @throws IllegalArgumentException if a reference to the server is not
386 * held (i.e. it wasn't created by
387 * {@link #createMBeanServer(String)}
388 * or this method has already been called
390 * @throws SecurityException if a security manager exists and the
391 * caller's permissions don't imply {@link
392 * MBeanServerPermission(String)}("releaseMBeanServer")
394 public static void releaseMBeanServer(MBeanServer server
)
396 SecurityManager sm
= System
.getSecurityManager();
398 sm
.checkPermission(new MBeanServerPermission("releaseMBeanServer"));
399 Iterator
<MBeanServer
> i
= servers
.values().iterator();
402 MBeanServer s
= i
.next();
409 throw new IllegalArgumentException("The server given is not referenced.");