gomp-20050608-branch/libjava/classpath/java/rmi/server/RMIClassLoader.java

   1 /* RMIClassLoader.java --
   2    Copyright (c) 1996, 1997, 1998, 1999, 2002, 2003, 2004
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GNU Classpath.
   6
   7 GNU Classpath is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU Classpath is distributed in the hope that it will be useful, but
  13 WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Classpath; see the file COPYING.  If not, write to the
  19 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20 02110-1301 USA.
  21
  22 Linking this library statically or dynamically with other modules is
  23 making a combined work based on this library.  Thus, the terms and
  24 conditions of the GNU General Public License cover the whole
  25 combination.
  26
  27 As a special exception, the copyright holders of this library give you
  28 permission to link this library with independent modules to produce an
  29 executable, regardless of the license terms of these independent
  30 modules, and to copy and distribute the resulting executable under
  31 terms of your choice, provided that you also meet, for each linked
  32 independent module, the terms and conditions of the license of that
  33 module.  An independent module is a module which is not derived from
  34 or based on this library.  If you modify this library, you may extend
  35 this exception to your version of the library, but you are not
  36 obligated to do so.  If you do not wish to do so, delete this
  37 exception statement from your version. */
  38
  39 package java.rmi.server;
  40
  41 import gnu.java.rmi.server.RMIClassLoaderImpl;
  42
  43 import java.net.MalformedURLException;
  44 import java.net.URL;
  45
  46 /**
  47  * This class provides a set of public static utility methods for supporting
  48  * network-based class loading in RMI. These methods are called by RMI's
  49  * internal marshal streams to implement the dynamic class loading of types for
  50  * RMI parameters and return values.
  51  */
  52 public class RMIClassLoader
  53 {
  54   /**
  55    * This class isn't intended to be instantiated.
  56    */
  57   private RMIClassLoader() {}
  58
  59   /**
  60    * @deprecated
  61    */
  62   public static Class loadClass(String name)
  63     throws MalformedURLException, ClassNotFoundException
  64   {
  65     return loadClass("", name);
  66   }
  67
  68   public static Class loadClass(String codebase, String name)
  69     throws MalformedURLException, ClassNotFoundException
  70   {
  71     RMIClassLoaderSpi spi = getProviderInstance();
  72     if (spi == null)
  73       spi = getDefaultProviderInstance();
  74     return spi.loadClass(codebase, name, null);
  75   }
  76
  77   public static Class loadClass(String codebase, String name,
  78                                 ClassLoader defaultLoader)
  79     throws MalformedURLException, ClassNotFoundException
  80   {
  81     RMIClassLoaderSpi spi = getProviderInstance();
  82     if (spi == null)
  83       spi = getDefaultProviderInstance();
  84     return spi.loadClass(codebase, name, defaultLoader);
  85   }
  86
  87   /**
  88    * Loads a class from <code>codeBase</code>.
  89    *
  90    * This method delegates to
  91    * {@link RMIClassLoaderSpi#loadClass(String, String, ClassLoader)} and
  92    * passes <code>codeBase.toString()</code> as first argument,
  93    * <code>name</code> as second argument and <code>null</code> as third
  94    * argument.
  95    *
  96    * @param codeBase the code base from which to load the class
  97    * @param name the name of the class
  98    *
  99    * @return the loaded class
 100    *
 101    * @throws MalformedURLException if the URL is not well formed
 102    * @throws ClassNotFoundException if the requested class cannot be found
 103    */
 104   public static Class loadClass(URL codeBase, String name)
 105     throws MalformedURLException, ClassNotFoundException
 106   {
 107     RMIClassLoaderSpi spi = getProviderInstance();
 108     if (spi == null)
 109       spi = getDefaultProviderInstance();
 110     return spi.loadClass(codeBase.toString(), name, null);
 111   }
 112
 113   /**
 114    * Gets a classloader for the given codebase and with the current
 115    * context classloader as parent.
 116    *
 117    * @param codebase
 118    *
 119    * @return a classloader for the given codebase
 120    *
 121    * @throws MalformedURLException if the codebase contains a malformed URL
 122    */
 123   public static ClassLoader getClassLoader(String codebase)
 124     throws MalformedURLException
 125   {
 126     RMIClassLoaderSpi spi = getProviderInstance();
 127     if (spi == null)
 128       spi = getDefaultProviderInstance();
 129     return spi.getClassLoader(codebase);
 130   }
 131
 132   /**
 133    * Returns a string representation of the network location where a remote
 134    * endpoint can get the class-definition of the given class.
 135    *
 136    * @param cl
 137    *
 138    * @return a space seperated list of URLs where the class-definition
 139    * of cl may be found
 140    */
 141   public static String getClassAnnotation(Class cl)
 142   {
 143     RMIClassLoaderSpi spi = getProviderInstance();
 144     if (spi == null)
 145       spi = getDefaultProviderInstance();
 146     return spi.getClassAnnotation(cl);
 147   }
 148
 149   /**
 150    * @deprecated
 151    */
 152   public static Object getSecurityContext (ClassLoader loader)
 153   {
 154     throw new Error ("Not implemented");
 155   }
 156
 157   /**
 158    * Returns the default service provider for <code>RMIClassLoader</code>.
 159    *
 160    * @return the default provider for <code>RMIClassLoader</code>
 161    */
 162   public static RMIClassLoaderSpi getDefaultProviderInstance()
 163   {
 164     return RMIClassLoaderImpl.getInstance();
 165   }
 166
 167   /**
 168    * Chooses, instantiates and returns a service provider.
 169    *
 170    * @return a service provider
 171    */
 172   private static RMIClassLoaderSpi getProviderInstance()
 173   {
 174     // TODO: Do something more useful here.
 175     return null;
 176   }
 177 }