J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1999-2004 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 com.sun.jndi.rmi.registry; |
| 27 | |
| 28 | |
| 29 | import java.util.Enumeration; |
| 30 | import java.util.Hashtable; |
| 31 | |
| 32 | import javax.naming.*; |
| 33 | import javax.naming.spi.*; |
| 34 | |
| 35 | import com.sun.jndi.url.rmi.rmiURLContextFactory; |
| 36 | |
| 37 | /** |
| 38 | * A RegistryContextFactory takes an RMI registry reference, and |
| 39 | * creates the corresponding RMI object or registry context. In |
| 40 | * addition, it serves as the initial context factory when using an |
| 41 | * RMI registry as an initial context. |
| 42 | *<p> |
| 43 | * When an initial context is being created, the environment |
| 44 | * property "java.naming.provider.url" should contain the RMI URL of |
| 45 | * the appropriate registry. Otherwise, the default URL "rmi:" is used. |
| 46 | *<p> |
| 47 | * An RMI registry reference contains one or more StringRefAddrs of |
| 48 | * type "URL", each containing a single RMI URL. Other addresses |
| 49 | * are ignored. Multiple URLs represent alternative addresses for the |
| 50 | * same logical resource. The order of the addresses is not significant. |
| 51 | * |
| 52 | * @author Scott Seligman |
| 53 | */ |
| 54 | |
| 55 | |
| 56 | public class RegistryContextFactory |
| 57 | implements ObjectFactory, InitialContextFactory |
| 58 | { |
| 59 | /** |
| 60 | * The type of each address in an RMI registry reference. |
| 61 | */ |
| 62 | public final static String ADDRESS_TYPE = "URL"; |
| 63 | |
| 64 | public Context getInitialContext(Hashtable<?,?> env) throws NamingException { |
| 65 | |
| 66 | if (env != null) { |
| 67 | env = (Hashtable) env.clone(); |
| 68 | } |
| 69 | return URLToContext(getInitCtxURL(env), env); |
| 70 | } |
| 71 | |
| 72 | public Object getObjectInstance(Object ref, Name name, Context nameCtx, |
| 73 | Hashtable<?,?> env) |
| 74 | throws NamingException |
| 75 | { |
| 76 | if (!isRegistryRef(ref)) { |
| 77 | return null; |
| 78 | } |
| 79 | /* |
| 80 | * No need to clone env here. If getObjectInstance() |
| 81 | * returns something other than a RegistryContext (which |
| 82 | * happens if you're looking up an object bound in the |
| 83 | * registry, as opposed to looking up the registry itself), |
| 84 | * then the context is GCed right away and there's no need to |
| 85 | * clone the environment. If getObjectInstance() returns a |
| 86 | * RegistryContext, then it still goes through |
| 87 | * GenericURLContext, which calls RegistryContext.lookup() |
| 88 | * with an empty name, which clones the environment. |
| 89 | */ |
| 90 | Object obj = URLsToObject(getURLs((Reference)ref), env); |
| 91 | if (obj instanceof RegistryContext) { |
| 92 | RegistryContext ctx = (RegistryContext)obj; |
| 93 | ctx.reference = (Reference)ref; |
| 94 | } |
| 95 | return obj; |
| 96 | } |
| 97 | |
| 98 | private static Context URLToContext(String url, Hashtable env) |
| 99 | throws NamingException |
| 100 | { |
| 101 | rmiURLContextFactory factory = new rmiURLContextFactory(); |
| 102 | Object obj = factory.getObjectInstance(url, null, null, env); |
| 103 | |
| 104 | if (obj instanceof Context) { |
| 105 | return (Context)obj; |
| 106 | } else { |
| 107 | throw (new NotContextException(url)); |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | private static Object URLsToObject(String[] urls, Hashtable env) |
| 112 | throws NamingException |
| 113 | { |
| 114 | rmiURLContextFactory factory = new rmiURLContextFactory(); |
| 115 | return factory.getObjectInstance(urls, null, null, env); |
| 116 | } |
| 117 | |
| 118 | /** |
| 119 | * Reads environment to find URL of initial context. |
| 120 | * The default URL is "rmi:". |
| 121 | */ |
| 122 | private static String getInitCtxURL(Hashtable env) { |
| 123 | |
| 124 | final String defaultURL = "rmi:"; |
| 125 | |
| 126 | String url = null; |
| 127 | if (env != null) { |
| 128 | url = (String)env.get(Context.PROVIDER_URL); |
| 129 | } |
| 130 | return ((url != null) ? url : defaultURL); |
| 131 | } |
| 132 | |
| 133 | /** |
| 134 | * Returns true if argument is an RMI registry reference. |
| 135 | */ |
| 136 | private static boolean isRegistryRef(Object obj) { |
| 137 | |
| 138 | if (!(obj instanceof Reference)) { |
| 139 | return false; |
| 140 | } |
| 141 | String thisClassName = RegistryContextFactory.class.getName(); |
| 142 | Reference ref = (Reference)obj; |
| 143 | |
| 144 | return thisClassName.equals(ref.getFactoryClassName()); |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * Returns the URLs contained within an RMI registry reference. |
| 149 | */ |
| 150 | private static String[] getURLs(Reference ref) throws NamingException { |
| 151 | |
| 152 | int size = 0; // number of URLs |
| 153 | String[] urls = new String[ref.size()]; |
| 154 | |
| 155 | Enumeration addrs = ref.getAll(); |
| 156 | while (addrs.hasMoreElements()) { |
| 157 | RefAddr addr = (RefAddr)addrs.nextElement(); |
| 158 | |
| 159 | if ((addr instanceof StringRefAddr) && |
| 160 | addr.getType().equals(ADDRESS_TYPE)) { |
| 161 | |
| 162 | urls[size++] = (String)addr.getContent(); |
| 163 | } |
| 164 | } |
| 165 | if (size == 0) { |
| 166 | throw (new ConfigurationException( |
| 167 | "Reference contains no valid addresses")); |
| 168 | } |
| 169 | |
| 170 | // Trim URL array down to size. |
| 171 | if (size == ref.size()) { |
| 172 | return urls; |
| 173 | } |
| 174 | String[] urls2 = new String[size]; |
| 175 | System.arraycopy(urls, 0, urls2, 0, size); |
| 176 | return urls2; |
| 177 | } |
| 178 | } |