Java > Open Source Codes > com > sun > jmx > remote > util > EnvHelp


1 /*
2  * @(#)EnvHelp.java 1.36 05/08/31
3  *
4  * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
5  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
6  */
7
8 package com.sun.jmx.remote.util;
9
10 import java.io.IOException ;
11 import java.io.ObjectOutputStream ;
12 import java.io.OutputStream ;
13 import java.util.Collection ;
14 import java.util.HashMap ;
15 import java.util.Hashtable ;
16 import java.util.Iterator ;
17 import java.util.Map ;
18 import java.util.SortedMap ;
19 import java.util.SortedSet ;
20 import java.util.StringTokenizer ;
21 import java.util.TreeMap ;
22 import java.util.TreeSet ;
23
24 import java.security.AccessController ;
25 import java.security.PrivilegedAction ;
26 import java.security.PrivilegedActionException ;
27 import java.security.PrivilegedExceptionAction ;
28
29 import javax.management.ObjectName ;
30 import javax.management.MBeanServer ;
31 import javax.management.InstanceNotFoundException ;
32 import javax.management.remote.JMXConnectorFactory ;
33 import javax.management.remote.JMXConnectorServerFactory ;
34 import com.sun.jmx.mbeanserver.GetPropertyAction;
35
36 public class EnvHelp {
37
38     /**
39      * <p>Name of the attribute that specifies a default class loader
40      * object.
41      * The value associated with this attribute is a ClassLoader object</p>
42      */
43     private static final String DEFAULT_CLASS_LOADER =
44         JMXConnectorFactory.DEFAULT_CLASS_LOADER;
45
46     /**
47      * <p>Name of the attribute that specifies a default class loader
48      * ObjectName.
49      * The value associated with this attribute is an ObjectName object</p>
50      */
51     private static final String DEFAULT_CLASS_LOADER_NAME =
52         JMXConnectorServerFactory.DEFAULT_CLASS_LOADER_NAME;
53
54     /**
55      * Get the Connector Server default class loader.
56      * <p>
57      * Returns:
58      * <p>
59      * <ul>
60      * <li>
61      * The ClassLoader object found in <var>env</var> for
62      * <tt>jmx.remote.default.class.loader</tt>, if any.
63      * </li>
64      * <li>
65      * The ClassLoader pointed to by the ObjectName found in
66      * <var>env</var> for <tt>jmx.remote.default.class.loader.name</tt>,
67      * and registered in <var>mbs</var> if any.
68      * </li>
69      * <li>
70      * The current thread's context classloader otherwise.
71      * </li>
72      * </ul>
73      *
74      * @param env Environment attributes.
75      * @param mbs The MBeanServer for which the connector server provides
76      * remote access.
77      *
78      * @return the connector server's default class loader.
79      *
80      * @exception IllegalArgumentException if one of the following is true:
81      * <ul>
82      * <li>both
83      * <tt>jmx.remote.default.class.loader</tt> and
84      * <tt>jmx.remote.default.class.loader.name</tt> are specified,
85      * </li>
86      * <li>or
87      * <tt>jmx.remote.default.class.loader</tt> is not
88      * an instance of {@link ClassLoader},
89      * </li>
90      * <li>or
91      * <tt>jmx.remote.default.class.loader.name</tt> is not
92      * an instance of {@link ObjectName},
93      * </li>
94      * <li>or
95      * <tt>jmx.remote.default.class.loader.name</tt> is specified
96      * but <var>mbs</var> is null.
97      * </li>
98      * @exception InstanceNotFoundException if
99      * <tt>jmx.remote.default.class.loader.name</tt> is specified
100      * and the ClassLoader MBean is not found in <var>mbs</var>.
101      */
102     public static ClassLoader resolveServerClassLoader(Map env,
103                                                        MBeanServer mbs)
104         throws InstanceNotFoundException {
105
106         if (env == null)
107             return Thread.currentThread().getContextClassLoader();
108
109         Object loader = env.get(DEFAULT_CLASS_LOADER);
110         Object name = env.get(DEFAULT_CLASS_LOADER_NAME);
111
112         if (loader != null && name != null) {
113             final String msg = "Only one of " +
114                 DEFAULT_CLASS_LOADER + " or " +
115                 DEFAULT_CLASS_LOADER_NAME +
116                 " should be specified.";
117             throw new IllegalArgumentException (msg);
118         }
119
120         if (loader == null && name == null)
121             return Thread.currentThread().getContextClassLoader();
122
123         if (loader != null) {
124             if (loader instanceof ClassLoader ) {
125                 return (ClassLoader ) loader;
126             } else {
127                 final String msg =
128                     "ClassLoader object is not an instance of " +
129                     ClassLoader .class.getName() + " : " +
130                     loader.getClass().getName();
131                 throw new IllegalArgumentException (msg);
132             }
133         }
134
135         ObjectName on;
136         if (name instanceof ObjectName ) {
137             on = (ObjectName ) name;
138         } else {
139             final String msg =
140                 "ClassLoader name is not an instance of " +
141                 ObjectName .class.getName() + " : " +
142                 name.getClass().getName();
143             throw new IllegalArgumentException (msg);
144         }
145
146         if (mbs == null)
147             throw new IllegalArgumentException ("Null MBeanServer object");
148
149         return mbs.getClassLoader(on);
150     }
151
152     /**
153      * Get the Connector Client default class loader.
154      * <p>
155      * Returns:
156      * <p>
157      * <ul>
158      * <li>
159      * The ClassLoader object found in <var>env</var> for
160      * <tt>jmx.remote.default.class.loader</tt>, if any.
161      * </li>
162      * <li>The <tt>Thread.currentThread().getContextClassLoader()</tt>
163      * otherwise.
164      * </li>
165      * </ul>
166      * <p>
167      * Usually a Connector Client will call
168      * <pre>
169      * ClassLoader dcl = EnvHelp.resolveClientClassLoader(env);
170      * </pre>
171      * in its <tt>connect(Map env)</tt> method.
172      *
173      * @return The connector client default class loader.
174      *
175      * @exception IllegalArgumentException if
176      * <tt>jmx.remote.default.class.loader</tt> is specified
177      * and is not an instance of {@link ClassLoader}.
178      */
179     public static ClassLoader resolveClientClassLoader(Map env) {
180
181         if (env == null)
182             return Thread.currentThread().getContextClassLoader();
183
184         Object loader = env.get(DEFAULT_CLASS_LOADER);
185
186         if (loader == null)
187             return Thread.currentThread().getContextClassLoader();
188
189         if (loader instanceof ClassLoader ) {
190             return (ClassLoader ) loader;
191         } else {
192             final String msg =
193                 "ClassLoader object is not an instance of " +
194                 ClassLoader .class.getName() + " : " +
195                 loader.getClass().getName();
196             throw new IllegalArgumentException (msg);
197         }
198     }
199
200     /**
201      * Initialise the cause field of a {@code Throwable} object.
202      *
203      * @param throwable The {@code Throwable} on which the cause is set.
204      * @param cause The cause to set on the supplied {@code Throwable}.
205      * @return the {@code Throwable} with the cause field initialised.
206      */
207     public static <T extends Throwable > T initCause(T throwable,
208                             Throwable cause) {
209     throwable.initCause(cause);
210     return throwable;
211     }
212
213     /**
214      * Returns the cause field of a Throwable object.
215      * The cause field can be got only if <var>t</var> has an
216      * {@link Throwable#getCause()} method (JDK Version >= 1.4)
217      * @param t Throwable on which the cause must be set.
218      * @return the cause if getCause() succeeded and the got value is not
219      * null, otherwise return the <var>t</var>.
220      */
221     public static Throwable getCause(Throwable t) {
222         Throwable ret = t;
223
224         try {
225             java.lang.reflect.Method getCause =
226         t.getClass().getMethod("getCause", (Class []) null);
227             ret = (Throwable )getCause.invoke(t, (Object []) null);
228
229         } catch (Exception e) {
230         // OK.
231 // it must be older than 1.4.
232 }
233         return (ret != null) ? ret: t;
234     }
235
236
237     /**
238      * <p>Name of the attribute that specifies the size of a notification
239      * buffer for a connector server. The default value is 1000.
240      */
241     public static final String BUFFER_SIZE_PROPERTY =
242     "jmx.remote.x.notification.buffer.size";
243
244
245     /**
246      * Returns the size of a notification buffer for a connector server.
247      * The default value is 1000.
248      */
249     public static int getNotifBufferSize(Map env) {
250     int defaultQueueSize = 1000; // default value
251
252     // keep it for the compability for the fix:
253 // 6174229: Environment parameter should be notification.buffer.size
254 // instead of buffer.size
255 final String oldP = "jmx.remote.x.buffer.size";
256
257     // the default value re-specified in the system
258 try {
259         GetPropertyAction act = new GetPropertyAction(BUFFER_SIZE_PROPERTY);
260         String s = (String )AccessController.doPrivileged(act);
261         if (s != null) {
262         defaultQueueSize = Integer.parseInt(s);
263         } else { // try the old one
264 act = new GetPropertyAction(oldP);
265         s = (String )AccessController.doPrivileged(act);
266         if (s != null) {
267             defaultQueueSize = Integer.parseInt(s);
268         }
269         }
270     } catch (RuntimeException e) {
271         logger.warning("getNotifBufferSize",
272                "Can't use System property "+
273                BUFFER_SIZE_PROPERTY+ ": " + e);
274               logger.debug("getNotifBufferSize", e);
275     }
276
277     int queueSize = defaultQueueSize;
278
279     try {
280         if (env.containsKey(BUFFER_SIZE_PROPERTY)) {
281         queueSize = (int)EnvHelp.getIntegerAttribute(env,BUFFER_SIZE_PROPERTY,
282                         defaultQueueSize,0,
283                         Integer.MAX_VALUE);
284         } else { // try the old one
285 queueSize = (int)EnvHelp.getIntegerAttribute(env,oldP,
286                         defaultQueueSize,0,
287                         Integer.MAX_VALUE);
288         }
289     } catch (RuntimeException e) {
290         logger.warning("getNotifBufferSize",
291                "Can't determine queuesize (using default): "+
292                e);
293         logger.debug("getNotifBufferSize", e);
294     }
295
296     return queueSize;
297     }
298
299     /**
300      * <p>Name of the attribute that specifies the maximum number of
301      * notifications that a client will fetch from its server.. The
302      * value associated with this attribute should be an
303      * <code>Integer</code> object. The default value is 1000.</p>
304      */
305     public static final String MAX_FETCH_NOTIFS =
306         "jmx.remote.x.notification.fetch.max";
307
308     /**
309      * Returns the maximum notification number which a client will
310      * fetch every time.
311      */
312     public static int getMaxFetchNotifNumber(Map env) {
313     return (int) getIntegerAttribute(env, MAX_FETCH_NOTIFS, 1000, 1,
314                      Integer.MAX_VALUE);
315     }
316
317     /**
318      * <p>Name of the attribute that specifies the timeout for a
319      * client to fetch notifications from its server. The value
320      * associated with this attribute should be a <code>Long</code>
321      * object. The default value is 60000 milleseconds.</p>
322      */
323     public static final String FETCH_TIMEOUT =
324         "jmx.remote.x.notification.fetch.timeout";
325
326     /**
327      * Returns the timeout for a client to fetch notifications.
328      */
329     public static long getFetchTimeout(Map env) {
330     return getIntegerAttribute(env, FETCH_TIMEOUT, 60000L, 0,
331                    Long.MAX_VALUE);
332     }
333
334     /**
335      * Get an integer-valued attribute with name <code>name</code>
336      * from <code>env</code>. If <code>env</code> is null, or does
337      * not contain an entry for <code>name</code>, return
338      * <code>defaultValue</code>. The value may be a Number, or it
339      * may be a String that is parsable as a long. It must be at
340      * least <code>minValue</code> and at most<code>maxValue</code>.
341      *
342      * @throws IllegalArgumentException if <code>env</code> contains
343      * an entry for <code>name</code> but it does not meet the
344      * constraints above.
345      */
346     public static long getIntegerAttribute(Map env, String name,
347                        long defaultValue, long minValue,
348                        long maxValue) {
349     final Object o;
350
351     if (env == null || (o = env.get(name)) == null)
352         return defaultValue;
353
354     final long result;
355
356     if (o instanceof Number )
357         result = ((Number ) o).longValue();
358     else if (o instanceof String ) {
359         result = Long.parseLong((String ) o);
360         /* May throw a NumberFormatException, which is an
361            IllegalArgumentException. */
362     } else {
363         final String msg =
364         "Attribute " + name + " value must be Integer or String: " + o;
365         throw new IllegalArgumentException (msg);
366     }
367
368     if (result < minValue) {
369         final String msg =
370         "Attribute " + name + " value must be at least " + minValue +
371         ": " + result;
372         throw new IllegalArgumentException (msg);
373     }
374
375     if (result > maxValue) {
376         final String msg =
377         "Attribute " + name + " value must be at most " + maxValue +
378         ": " + result;
379         throw new IllegalArgumentException (msg);
380     }
381
382         return result;
383     }
384
385     public static final String DEFAULT_ORB="java.naming.corba.orb";
386
387     /* Check that all attributes have a key that is a String.
388        Could make further checks, e.g. appropriate types for attributes. */
389     public static void checkAttributes(Map attributes) {
390         for (Iterator it = attributes.keySet().iterator(); it.hasNext(); ) {
391             Object key = it.next();
392             if (!(key instanceof String )) {
393                 final String msg =
394                     "Attributes contain key that is not a string: " + key;
395                 throw new IllegalArgumentException (msg);
396             }
397         }
398     }
399
400     /* Return a writable map containing only those attributes that are
401        serializable, and that are not hidden by
402        jmx.remote.x.hidden.attributes or the default list of hidden
403        attributes. */
404     public static Map filterAttributes(Map attributes) {
405         if (logger.traceOn()) {
406             logger.trace("filterAttributes", "starts");
407         }
408
409         SortedMap map = new TreeMap (attributes);
410     purgeUnserializable(map.values());
411     hideAttributes(map);
412         return map;
413     }
414
415     /**
416      * Remove from the given Collection any element that is not a
417      * serializable object.
418      */
419     private static void purgeUnserializable(Collection objects) {
420     logger.trace("purgeUnserializable", "starts");
421     ObjectOutputStream oos = null;
422     int i = 0;
423     for (Iterator it = objects.iterator(); it.hasNext(); i++) {
424         Object v = it.next();
425
426         if (v == null || v instanceof String ) {
427         if (logger.traceOn()) {
428             logger.trace("purgeUnserializable",
429                  "Value trivially serializable: " + v);
430         }
431         continue;
432         }
433
434         try {
435         if (oos == null)
436             oos = new ObjectOutputStream (new SinkOutputStream());
437         oos.writeObject(v);
438         if (logger.traceOn()) {
439             logger.trace("purgeUnserializable",
440                  "Value serializable: " + v);
441         }
442         } catch (IOException e) {
443         if (logger.traceOn()) {
444             logger.trace("purgeUnserializable",
445                  "Value not serializable: " + v + ": " +
446                  e);
447         }
448         it.remove();
449         oos = null; // ObjectOutputStream invalid after exception
450 }
451     }
452     }
453
454     /**
455        The value of this attribute, if present, is a string specifying
456        what other attributes should not appear in
457        JMXConnectorServer.getAttributes(). It is a space-separated
458        list of attribute patterns, where each pattern is either an
459        attribute name, or an attribute prefix followed by a "*"
460        character. The "*" has no special significance anywhere except
461        at the end of a pattern. By default, this list is added to the
462        list defined by {@link #DEFAULT_HIDDEN_ATTRIBUTES} (which
463        uses the same format). If the value of this attribute begins
464        with an "=", then the remainder of the string defines the
465        complete list of attribute patterns.
466      */
467     public static final String HIDDEN_ATTRIBUTES =
468     "jmx.remote.x.hidden.attributes";
469
470     /**
471        Default list of attributes not to show.
472        @see #HIDDEN_ATTRIBUTES
473      */
474     /* This list is copied directly from the spec, plus
475        java.naming.security.*. Most of the attributes here would have
476        been eliminated from the map anyway because they are typically
477        not serializable. But just in case they are, we list them here
478        to conform to the spec. */
479     public static final String DEFAULT_HIDDEN_ATTRIBUTES =
480     "java.naming.security.* " +
481     "jmx.remote.authenticator " +
482     "jmx.remote.context " +
483     "jmx.remote.default.class.loader " +
484     "jmx.remote.message.connection.server " +
485     "jmx.remote.object.wrapping " +
486     "jmx.remote.rmi.client.socket.factory " +
487     "jmx.remote.rmi.server.socket.factory " +
488     "jmx.remote.sasl.callback.handler " +
489     "jmx.remote.tls.socket.factory " +
490     "jmx.remote.x.access.file " +
491     "jmx.remote.x.password.file ";
492
493     private static final SortedSet defaultHiddenStrings = new TreeSet ();
494     private static final SortedSet defaultHiddenPrefixes = new TreeSet ();
495
496     private static void hideAttributes(SortedMap map) {
497     if (map.isEmpty())
498         return;
499
500     final SortedSet hiddenStrings;
501     final SortedSet hiddenPrefixes;
502
503     String hide = (String ) map.get(HIDDEN_ATTRIBUTES);
504     if (hide != null) {
505         if (hide.startsWith("="))
506         hide = hide.substring(1);
507         else
508         hide += " " + DEFAULT_HIDDEN_ATTRIBUTES;
509         hiddenStrings = new TreeSet ();
510         hiddenPrefixes = new TreeSet ();
511         parseHiddenAttributes(hide, hiddenStrings, hiddenPrefixes);
512     } else {
513         hide = DEFAULT_HIDDEN_ATTRIBUTES;
514         synchronized (defaultHiddenStrings) {
515         if (defaultHiddenStrings.isEmpty()) {
516             parseHiddenAttributes(hide,
517                       defaultHiddenStrings,
518                       defaultHiddenPrefixes);
519         }
520         hiddenStrings = defaultHiddenStrings;
521         hiddenPrefixes = defaultHiddenPrefixes;
522         }
523     }
524
525     /* Construct a string that is greater than any key in the map.
526        Setting a string-to-match or a prefix-to-match to this string
527        guarantees that we will never call next() on the corresponding
528        iterator. */
529     String sentinelKey = map.lastKey() + "X";
530     Iterator keyIterator = map.keySet().iterator();
531     Iterator stringIterator = hiddenStrings.iterator();
532     Iterator prefixIterator = hiddenPrefixes.iterator();
533
534     String nextString;
535     if (stringIterator.hasNext())
536         nextString = (String ) stringIterator.next();
537     else
538         nextString = sentinelKey;
539     String nextPrefix;
540     if (prefixIterator.hasNext())
541         nextPrefix = (String ) prefixIterator.next();
542     else
543         nextPrefix = sentinelKey;
544
545     /* Read each key in sorted order and, if it matches a string
546        or prefix, remove it. */
547     keys:
548     while (keyIterator.hasNext()) {
549         String key = (String ) keyIterator.next();
550
551         /* Continue through string-match values until we find one
552            that is either greater than the current key, or equal
553            to it. In the latter case, remove the key. */
554         int cmp = +1;
555         while ((cmp = nextString.compareTo(key)) < 0) {
556         if (stringIterator.hasNext())
557             nextString = (String ) stringIterator.next();
558         else
559             nextString = sentinelKey;
560         }
561         if (cmp == 0) {
562         keyIterator.remove();
563         continue keys;
564         }
565
566         /* Continue through the prefix values until we find one
567            that is either greater than the current key, or a
568            prefix of it. In the latter case, remove the key. */
569         while (nextPrefix.compareTo(key) <= 0) {
570         if (key.startsWith(nextPrefix)) {
571             keyIterator.remove();
572             continue keys;
573         }
574         if (prefixIterator.hasNext())
575             nextPrefix = (String ) prefixIterator.next();
576         else
577             nextPrefix = sentinelKey;
578         }
579     }
580     }
581
582     private static void parseHiddenAttributes(String hide,
583                           SortedSet hiddenStrings,
584                           SortedSet hiddenPrefixes) {
585     final StringTokenizer tok = new StringTokenizer (hide);
586     while (tok.hasMoreTokens()) {
587         String s = tok.nextToken();
588         if (s.endsWith("*"))
589         hiddenPrefixes.add(s.substring(0, s.length() - 1));
590         else
591         hiddenStrings.add(s);
592     }
593     }
594
595     /**
596      * <p>Name of the attribute that specifies the timeout to keep a
597      * server side connection after answering last client request.
598      * The default value is 120000 milliseconds.</p>
599      */
600     public static final String SERVER_CONNECTION_TIMEOUT =
601     "jmx.remote.x.server.connection.timeout";
602
603     /**
604      * Returns the server side connection timeout.
605      */
606     public static long getServerConnectionTimeout(Map env) {
607     return getIntegerAttribute(env, SERVER_CONNECTION_TIMEOUT, 120000L,
608                    0, Long.MAX_VALUE);
609     }
610
611     /**
612      * <p>Name of the attribute that specifies the period in
613      * millisecond for a client to check its connection. The default
614      * value is 60000 milliseconds.</p>
615      */
616     public static final String CLIENT_CONNECTION_CHECK_PERIOD =
617     "jmx.remote.x.client.connection.check.period";
618
619     /**
620      * Returns the client connection check oeriod.
621      */
622     public static long getConnectionCheckPeriod(Map env) {
623     return getIntegerAttribute(env, CLIENT_CONNECTION_CHECK_PERIOD, 60000L,
624                    0, Long.MAX_VALUE);
625     }
626
627     /**
628      * Converts a map into a valid hash table, i.e.
629      * it removes all the 'null' values from the map.
630      */
631     public static Hashtable mapToHashtable(Map map) {
632         HashMap m = new HashMap (map);
633         if (m.containsKey(null)) m.remove(null);
634         for (Iterator i = m.values().iterator(); i.hasNext(); )
635             if (i.next() == null) i.remove();
636         return new Hashtable (m);
637     }
638
639     private static final class SinkOutputStream extends OutputStream {
640     public void write(byte[] b, int off, int len) {}
641     public void write(int b) {}
642     }
643
644     private static final ClassLogger logger =
645     new ClassLogger("javax.management.remote.misc", "EnvHelp");
646 }
647

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