J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2000-2006 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package java.rmi.server; |
| 27 | |
| 28 | import java.net.MalformedURLException; |
| 29 | import java.net.URL; |
| 30 | |
| 31 | /** |
| 32 | * <code>RMIClassLoaderSpi</code> is the service provider interface for |
| 33 | * <code>RMIClassLoader</code>. |
| 34 | * |
| 35 | * In particular, an <code>RMIClassLoaderSpi</code> instance provides an |
| 36 | * implementation of the following static methods of |
| 37 | * <code>RMIClassLoader</code>: |
| 38 | * |
| 39 | * <ul> |
| 40 | * |
| 41 | * <li>{@link RMIClassLoader#loadClass(URL,String)} |
| 42 | * <li>{@link RMIClassLoader#loadClass(String,String)} |
| 43 | * <li>{@link RMIClassLoader#loadClass(String,String,ClassLoader)} |
| 44 | * <li>{@link RMIClassLoader#loadProxyClass(String,String[],ClassLoader)} |
| 45 | * <li>{@link RMIClassLoader#getClassLoader(String)} |
| 46 | * <li>{@link RMIClassLoader#getClassAnnotation(Class)} |
| 47 | * |
| 48 | * </ul> |
| 49 | * |
| 50 | * When one of those methods is invoked, its behavior is to delegate |
| 51 | * to a corresponding method on an instance of this class. |
| 52 | * The details of how each method delegates to the provider instance is |
| 53 | * described in the documentation for each particular method. |
| 54 | * See the documentation for {@link RMIClassLoader} for a description |
| 55 | * of how a provider instance is chosen. |
| 56 | * |
| 57 | * @author Peter Jones |
| 58 | * @author Laird Dornin |
| 59 | * @see RMIClassLoader |
| 60 | * @since 1.4 |
| 61 | */ |
| 62 | public abstract class RMIClassLoaderSpi { |
| 63 | |
| 64 | /** |
| 65 | * Provides the implementation for |
| 66 | * {@link RMIClassLoader#loadClass(URL,String)}, |
| 67 | * {@link RMIClassLoader#loadClass(String,String)}, and |
| 68 | * {@link RMIClassLoader#loadClass(String,String,ClassLoader)}. |
| 69 | * |
| 70 | * Loads a class from a codebase URL path, optionally using the |
| 71 | * supplied loader. |
| 72 | * |
| 73 | * Typically, a provider implementation will attempt to |
| 74 | * resolve the named class using the given <code>defaultLoader</code>, |
| 75 | * if specified, before attempting to resolve the class from the |
| 76 | * codebase URL path. |
| 77 | * |
| 78 | * <p>An implementation of this method must either return a class |
| 79 | * with the given name or throw an exception. |
| 80 | * |
| 81 | * @param codebase the list of URLs (separated by spaces) to load |
| 82 | * the class from, or <code>null</code> |
| 83 | * |
| 84 | * @param name the name of the class to load |
| 85 | * |
| 86 | * @param defaultLoader additional contextual class loader |
| 87 | * to use, or <code>null</code> |
| 88 | * |
| 89 | * @return the <code>Class</code> object representing the loaded class |
| 90 | * |
| 91 | * @throws MalformedURLException if <code>codebase</code> is |
| 92 | * non-<code>null</code> and contains an invalid URL, or |
| 93 | * if <code>codebase</code> is <code>null</code> and a provider-specific |
| 94 | * URL used to load classes is invalid |
| 95 | * |
| 96 | * @throws ClassNotFoundException if a definition for the class |
| 97 | * could not be found at the specified location |
| 98 | */ |
| 99 | public abstract Class<?> loadClass(String codebase, String name, |
| 100 | ClassLoader defaultLoader) |
| 101 | throws MalformedURLException, ClassNotFoundException; |
| 102 | |
| 103 | /** |
| 104 | * Provides the implementation for |
| 105 | * {@link RMIClassLoader#loadProxyClass(String,String[],ClassLoader)}. |
| 106 | * |
| 107 | * Loads a dynamic proxy class (see {@link java.lang.reflect.Proxy} |
| 108 | * that implements a set of interfaces with the given names |
| 109 | * from a codebase URL path, optionally using the supplied loader. |
| 110 | * |
| 111 | * <p>An implementation of this method must either return a proxy |
| 112 | * class that implements the named interfaces or throw an exception. |
| 113 | * |
| 114 | * @param codebase the list of URLs (space-separated) to load |
| 115 | * classes from, or <code>null</code> |
| 116 | * |
| 117 | * @param interfaces the names of the interfaces for the proxy class |
| 118 | * to implement |
| 119 | * |
| 120 | * @return a dynamic proxy class that implements the named interfaces |
| 121 | * |
| 122 | * @param defaultLoader additional contextual class loader |
| 123 | * to use, or <code>null</code> |
| 124 | * |
| 125 | * @throws MalformedURLException if <code>codebase</code> is |
| 126 | * non-<code>null</code> and contains an invalid URL, or |
| 127 | * if <code>codebase</code> is <code>null</code> and a provider-specific |
| 128 | * URL used to load classes is invalid |
| 129 | * |
| 130 | * @throws ClassNotFoundException if a definition for one of |
| 131 | * the named interfaces could not be found at the specified location, |
| 132 | * or if creation of the dynamic proxy class failed (such as if |
| 133 | * {@link java.lang.reflect.Proxy#getProxyClass(ClassLoader,Class[])} |
| 134 | * would throw an <code>IllegalArgumentException</code> for the given |
| 135 | * interface list) |
| 136 | */ |
| 137 | public abstract Class<?> loadProxyClass(String codebase, |
| 138 | String[] interfaces, |
| 139 | ClassLoader defaultLoader) |
| 140 | throws MalformedURLException, ClassNotFoundException; |
| 141 | |
| 142 | /** |
| 143 | * Provides the implementation for |
| 144 | * {@link RMIClassLoader#getClassLoader(String)}. |
| 145 | * |
| 146 | * Returns a class loader that loads classes from the given codebase |
| 147 | * URL path. |
| 148 | * |
| 149 | * <p>If there is a security manger, its <code>checkPermission</code> |
| 150 | * method will be invoked with a |
| 151 | * <code>RuntimePermission("getClassLoader")</code> permission; |
| 152 | * this could result in a <code>SecurityException</code>. |
| 153 | * The implementation of this method may also perform further security |
| 154 | * checks to verify that the calling context has permission to connect |
| 155 | * to all of the URLs in the codebase URL path. |
| 156 | * |
| 157 | * @param codebase the list of URLs (space-separated) from which |
| 158 | * the returned class loader will load classes from, or <code>null</code> |
| 159 | * |
| 160 | * @return a class loader that loads classes from the given codebase URL |
| 161 | * path |
| 162 | * |
| 163 | * @throws MalformedURLException if <code>codebase</code> is |
| 164 | * non-<code>null</code> and contains an invalid URL, or |
| 165 | * if <code>codebase</code> is <code>null</code> and a provider-specific |
| 166 | * URL used to identify the class loader is invalid |
| 167 | * |
| 168 | * @throws SecurityException if there is a security manager and the |
| 169 | * invocation of its <code>checkPermission</code> method fails, or |
| 170 | * if the caller does not have permission to connect to all of the |
| 171 | * URLs in the codebase URL path |
| 172 | */ |
| 173 | public abstract ClassLoader getClassLoader(String codebase) |
| 174 | throws MalformedURLException; // SecurityException |
| 175 | |
| 176 | /** |
| 177 | * Provides the implementation for |
| 178 | * {@link RMIClassLoader#getClassAnnotation(Class)}. |
| 179 | * |
| 180 | * Returns the annotation string (representing a location for |
| 181 | * the class definition) that RMI will use to annotate the class |
| 182 | * descriptor when marshalling objects of the given class. |
| 183 | * |
| 184 | * @param cl the class to obtain the annotation for |
| 185 | * |
| 186 | * @return a string to be used to annotate the given class when |
| 187 | * it gets marshalled, or <code>null</code> |
| 188 | * |
| 189 | * @throws NullPointerException if <code>cl</code> is <code>null</code> |
| 190 | */ |
| 191 | public abstract String getClassAnnotation(Class<?> cl); |
| 192 | } |