libjava/classpath/javax/management/DefaultLoaderRepository.java

   1 /* DefaultLoaderRepository.java -- Manages class loaders for the servers.
   2    Copyright (C) 2007 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   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)
   9 any later version.
  10
  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.
  15
  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
  19 02110-1301 USA.
  20
  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
  24 combination.
  25
  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. */
  37
  38 package javax.management;
  39
  40 import java.util.List;
  41
  42 /**
  43  * Maintains a list of the {@link ClassLoader} instances
  44  * registered with the management servers, allowing it
  45  * to be used to load classes.  In early versions of the
  46  * JMX API, this class represented a shared repository for
  47  * the classloaders of all management servers.  The management
  48  * of classloaders is now decentralised and this class is
  49  * deprecated.  The old behaviour is emulated by consulting
  50  * the {@link MBeanServer#getClassLoaderRepository()} method
  51  * of all the servers obtained from
  52  * {@link MBeanServerFactory#findMBeanServer(String)}.  Use of
  53  * this class should be avoided in new code.
  54  *
  55  * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
  56  * @since 1.5
  57  * @deprecated Use {@link MBeanServer#getClassLoaderRepository()}
  58  *             instead.
  59  */
  60 @Deprecated public class DefaultLoaderRepository
  61 {
  62
  63   /**
  64    * Attempts to load the given class using class loaders
  65    * supplied by the repository of each {@link MBeanServer}.
  66    * The {@link ClassLoader#loadClass(String)}
  67    * method of each class loader is called.  If the method
  68    * returns successfully, then the returned {@link Class} instance
  69    * is returned.  If a {@link ClassNotFoundException} is thrown,
  70    * then the next loader is tried.  Any other exception thrown
  71    * by the method is passed back to the caller.  This method
  72    * throws a {@link ClassNotFoundException} itself if all the
  73    * class loaders listed prove fruitless.
  74    *
  75    * @param name the name of the class to load.
  76    * @return the loaded class.
  77    * @throws ClassNotFoundException if all the class loaders fail
  78    *                                to load the class.
  79    */
  80   // API issue with lack of <?> on Class
  81   @SuppressWarnings("rawtypes")
  82   public static Class loadClass(String name)
  83     throws ClassNotFoundException
  84   {
  85     List<MBeanServer> servers = MBeanServerFactory.findMBeanServer(null);
  86     for (MBeanServer server : servers)
  87       {
  88         try
  89           {
  90             return server.getClassLoaderRepository().loadClass(name);
  91           }
  92         catch (ClassNotFoundException e)
  93           {
  94             /* Ignored; try the next server. */
  95           }
  96       }
  97     throw new ClassNotFoundException("The class loaders of all registered " +
  98                                      "servers failed to load the class, " +
  99                                      name);
 100   }
 101
 102   /**
 103    * <p>
 104    * Attempts to load the given class using class loaders
 105    * supplied by the repository of each {@link MBeanServer}.
 106    * The {@link ClassLoader#loadClass(String)}
 107    * method of each class loader is called.  If the method
 108    * returns successfully, then the returned {@link Class} instance
 109    * is returned.  If a {@link ClassNotFoundException} is thrown,
 110    * then the next loader is tried.  Any other exception thrown
 111    * by the method is passed back to the caller.  This method
 112    * throws a {@link ClassNotFoundException} itself if all the
 113    * class loaders listed prove fruitless.
 114    * </p>
 115    * <p>
 116    * Note that this method may deadlock if called simultaneously
 117    * by two class loaders in the list.
 118    * {@link loadClassBefore(ClassLoader, String)} should be used
 119    * in preference to this method to avoid this.
 120    * </p>
 121    *
 122    * @param exclude the class loader to exclude, or <code>null</code>
 123    *             to obtain the same behaviour as {@link #loadClass(String)}.
 124    * @param name the name of the class to load.
 125    * @return the loaded class.
 126    * @throws ClassNotFoundException if all the class loaders fail
 127    *                                to load the class.
 128    */
 129   // API issue with lack of <?> on Class
 130   @SuppressWarnings("rawtypes")
 131   public static Class loadClassWithout(ClassLoader exclude, String name)
 132     throws ClassNotFoundException
 133   {
 134     List<MBeanServer> servers = MBeanServerFactory.findMBeanServer(null);
 135     for (MBeanServer server : servers)
 136       {
 137         try
 138           {
 139             return server.getClassLoaderRepository().loadClassWithout(exclude,
 140                                                                       name);
 141           }
 142         catch (ClassNotFoundException e)
 143           {
 144             /* Ignored; try the next server. */
 145           }
 146       }
 147     throw new ClassNotFoundException("The class loaders of all registered " +
 148                                      "servers failed to load the class, " +
 149                                      name);
 150   }
 151
 152 }