J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1996-2005 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 | package java.rmi; |
| 26 | |
| 27 | import java.rmi.registry.*; |
| 28 | import java.net.MalformedURLException; |
| 29 | import java.net.URI; |
| 30 | import java.net.URISyntaxException; |
| 31 | |
| 32 | /** |
| 33 | * The <code>Naming</code> class provides methods for storing and obtaining |
| 34 | * references to remote objects in a remote object registry. Each method of |
| 35 | * the <code>Naming</code> class takes as one of its arguments a name that |
| 36 | * is a <code>java.lang.String</code> in URL format (without the |
| 37 | * scheme component) of the form: |
| 38 | * |
| 39 | * <PRE> |
| 40 | * //host:port/name |
| 41 | * </PRE> |
| 42 | * |
| 43 | * <P>where <code>host</code> is the host (remote or local) where the registry |
| 44 | * is located, <code>port</code> is the port number on which the registry |
| 45 | * accepts calls, and where <code>name</code> is a simple string uninterpreted |
| 46 | * by the registry. Both <code>host</code> and <code>port</code> are optional. |
| 47 | * If <code>host</code> is omitted, the host defaults to the local host. If |
| 48 | * <code>port</code> is omitted, then the port defaults to 1099, the |
| 49 | * "well-known" port that RMI's registry, <code>rmiregistry</code>, uses. |
| 50 | * |
| 51 | * <P><em>Binding</em> a name for a remote object is associating or |
| 52 | * registering a name for a remote object that can be used at a later time to |
| 53 | * look up that remote object. A remote object can be associated with a name |
| 54 | * using the <code>Naming</code> class's <code>bind</code> or |
| 55 | * <code>rebind</code> methods. |
| 56 | * |
| 57 | * <P>Once a remote object is registered (bound) with the RMI registry on the |
| 58 | * local host, callers on a remote (or local) host can lookup the remote |
| 59 | * object by name, obtain its reference, and then invoke remote methods on the |
| 60 | * object. A registry may be shared by all servers running on a host or an |
| 61 | * individual server process may create and use its own registry if desired |
| 62 | * (see <code>java.rmi.registry.LocateRegistry.createRegistry</code> method |
| 63 | * for details). |
| 64 | * |
| 65 | * @author Ann Wollrath |
| 66 | * @author Roger Riggs |
| 67 | * @since JDK1.1 |
| 68 | * @see java.rmi.registry.Registry |
| 69 | * @see java.rmi.registry.LocateRegistry |
| 70 | * @see java.rmi.registry.LocateRegistry#createRegistry(int) |
| 71 | */ |
| 72 | public final class Naming { |
| 73 | /** |
| 74 | * Disallow anyone from creating one of these |
| 75 | */ |
| 76 | private Naming() {} |
| 77 | |
| 78 | /** |
| 79 | * Returns a reference, a stub, for the remote object associated |
| 80 | * with the specified <code>name</code>. |
| 81 | * |
| 82 | * @param name a name in URL format (without the scheme component) |
| 83 | * @return a reference for a remote object |
| 84 | * @exception NotBoundException if name is not currently bound |
| 85 | * @exception RemoteException if registry could not be contacted |
| 86 | * @exception AccessException if this operation is not permitted |
| 87 | * @exception MalformedURLException if the name is not an appropriately |
| 88 | * formatted URL |
| 89 | * @since JDK1.1 |
| 90 | */ |
| 91 | public static Remote lookup(String name) |
| 92 | throws NotBoundException, |
| 93 | java.net.MalformedURLException, |
| 94 | RemoteException |
| 95 | { |
| 96 | ParsedNamingURL parsed = parseURL(name); |
| 97 | Registry registry = getRegistry(parsed); |
| 98 | |
| 99 | if (parsed.name == null) |
| 100 | return registry; |
| 101 | return registry.lookup(parsed.name); |
| 102 | } |
| 103 | |
| 104 | /** |
| 105 | * Binds the specified <code>name</code> to a remote object. |
| 106 | * |
| 107 | * @param name a name in URL format (without the scheme component) |
| 108 | * @param obj a reference for the remote object (usually a stub) |
| 109 | * @exception AlreadyBoundException if name is already bound |
| 110 | * @exception MalformedURLException if the name is not an appropriately |
| 111 | * formatted URL |
| 112 | * @exception RemoteException if registry could not be contacted |
| 113 | * @exception AccessException if this operation is not permitted (if |
| 114 | * originating from a non-local host, for example) |
| 115 | * @since JDK1.1 |
| 116 | */ |
| 117 | public static void bind(String name, Remote obj) |
| 118 | throws AlreadyBoundException, |
| 119 | java.net.MalformedURLException, |
| 120 | RemoteException |
| 121 | { |
| 122 | ParsedNamingURL parsed = parseURL(name); |
| 123 | Registry registry = getRegistry(parsed); |
| 124 | |
| 125 | if (obj == null) |
| 126 | throw new NullPointerException("cannot bind to null"); |
| 127 | |
| 128 | registry.bind(parsed.name, obj); |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Destroys the binding for the specified name that is associated |
| 133 | * with a remote object. |
| 134 | * |
| 135 | * @param name a name in URL format (without the scheme component) |
| 136 | * @exception NotBoundException if name is not currently bound |
| 137 | * @exception MalformedURLException if the name is not an appropriately |
| 138 | * formatted URL |
| 139 | * @exception RemoteException if registry could not be contacted |
| 140 | * @exception AccessException if this operation is not permitted (if |
| 141 | * originating from a non-local host, for example) |
| 142 | * @since JDK1.1 |
| 143 | */ |
| 144 | public static void unbind(String name) |
| 145 | throws RemoteException, |
| 146 | NotBoundException, |
| 147 | java.net.MalformedURLException |
| 148 | { |
| 149 | ParsedNamingURL parsed = parseURL(name); |
| 150 | Registry registry = getRegistry(parsed); |
| 151 | |
| 152 | registry.unbind(parsed.name); |
| 153 | } |
| 154 | |
| 155 | /** |
| 156 | * Rebinds the specified name to a new remote object. Any existing |
| 157 | * binding for the name is replaced. |
| 158 | * |
| 159 | * @param name a name in URL format (without the scheme component) |
| 160 | * @param obj new remote object to associate with the name |
| 161 | * @exception MalformedURLException if the name is not an appropriately |
| 162 | * formatted URL |
| 163 | * @exception RemoteException if registry could not be contacted |
| 164 | * @exception AccessException if this operation is not permitted (if |
| 165 | * originating from a non-local host, for example) |
| 166 | * @since JDK1.1 |
| 167 | */ |
| 168 | public static void rebind(String name, Remote obj) |
| 169 | throws RemoteException, java.net.MalformedURLException |
| 170 | { |
| 171 | ParsedNamingURL parsed = parseURL(name); |
| 172 | Registry registry = getRegistry(parsed); |
| 173 | |
| 174 | if (obj == null) |
| 175 | throw new NullPointerException("cannot bind to null"); |
| 176 | |
| 177 | registry.rebind(parsed.name, obj); |
| 178 | } |
| 179 | |
| 180 | /** |
| 181 | * Returns an array of the names bound in the registry. The names are |
| 182 | * URL-formatted (without the scheme component) strings. The array contains |
| 183 | * a snapshot of the names present in the registry at the time of the |
| 184 | * call. |
| 185 | * |
| 186 | * @param name a registry name in URL format (without the scheme |
| 187 | * component) |
| 188 | * @return an array of names (in the appropriate format) bound |
| 189 | * in the registry |
| 190 | * @exception MalformedURLException if the name is not an appropriately |
| 191 | * formatted URL |
| 192 | * @exception RemoteException if registry could not be contacted. |
| 193 | * @since JDK1.1 |
| 194 | */ |
| 195 | public static String[] list(String name) |
| 196 | throws RemoteException, java.net.MalformedURLException |
| 197 | { |
| 198 | ParsedNamingURL parsed = parseURL(name); |
| 199 | Registry registry = getRegistry(parsed); |
| 200 | |
| 201 | String prefix = ""; |
| 202 | if (parsed.port > 0 || !parsed.host.equals("")) |
| 203 | prefix += "//" + parsed.host; |
| 204 | if (parsed.port > 0) |
| 205 | prefix += ":" + parsed.port; |
| 206 | prefix += "/"; |
| 207 | |
| 208 | String[] names = registry.list(); |
| 209 | for (int i = 0; i < names.length; i++) { |
| 210 | names[i] = prefix + names[i]; |
| 211 | } |
| 212 | return names; |
| 213 | } |
| 214 | |
| 215 | /** |
| 216 | * Returns a registry reference obtained from information in the URL. |
| 217 | */ |
| 218 | private static Registry getRegistry(ParsedNamingURL parsed) |
| 219 | throws RemoteException |
| 220 | { |
| 221 | return LocateRegistry.getRegistry(parsed.host, parsed.port); |
| 222 | } |
| 223 | |
| 224 | /** |
| 225 | * Dissect Naming URL strings to obtain referenced host, port and |
| 226 | * object name. |
| 227 | * |
| 228 | * @return an object which contains each of the above |
| 229 | * components. |
| 230 | * |
| 231 | * @exception MalformedURLException if given url string is malformed |
| 232 | */ |
| 233 | private static ParsedNamingURL parseURL(String str) |
| 234 | throws MalformedURLException |
| 235 | { |
| 236 | try { |
| 237 | return intParseURL(str); |
| 238 | } catch (URISyntaxException ex) { |
| 239 | /* With RFC 3986 URI handling, 'rmi://:<port>' and |
| 240 | * '//:<port>' forms will result in a URI syntax exception |
| 241 | * Convert the authority to a localhost:<port> form |
| 242 | */ |
| 243 | MalformedURLException mue = new MalformedURLException( |
| 244 | "invalid URL String: " + str); |
| 245 | mue.initCause(ex); |
| 246 | int indexSchemeEnd = str.indexOf(':'); |
| 247 | int indexAuthorityBegin = str.indexOf("//:"); |
| 248 | if (indexAuthorityBegin < 0) { |
| 249 | throw mue; |
| 250 | } |
| 251 | if ((indexAuthorityBegin == 0) || |
| 252 | ((indexSchemeEnd > 0) && |
| 253 | (indexAuthorityBegin == indexSchemeEnd + 1))) { |
| 254 | int indexHostBegin = indexAuthorityBegin + 2; |
| 255 | String newStr = str.substring(0, indexHostBegin) + |
| 256 | "localhost" + |
| 257 | str.substring(indexHostBegin); |
| 258 | try { |
| 259 | return intParseURL(newStr); |
| 260 | } catch (URISyntaxException inte) { |
| 261 | throw mue; |
| 262 | } catch (MalformedURLException inte) { |
| 263 | throw inte; |
| 264 | } |
| 265 | } |
| 266 | throw mue; |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | private static ParsedNamingURL intParseURL(String str) |
| 271 | throws MalformedURLException, URISyntaxException |
| 272 | { |
| 273 | URI uri = new URI(str); |
| 274 | if (uri.isOpaque()) { |
| 275 | throw new MalformedURLException( |
| 276 | "not a hierarchical URL: " + str); |
| 277 | } |
| 278 | if (uri.getFragment() != null) { |
| 279 | throw new MalformedURLException( |
| 280 | "invalid character, '#', in URL name: " + str); |
| 281 | } else if (uri.getQuery() != null) { |
| 282 | throw new MalformedURLException( |
| 283 | "invalid character, '?', in URL name: " + str); |
| 284 | } else if (uri.getUserInfo() != null) { |
| 285 | throw new MalformedURLException( |
| 286 | "invalid character, '@', in URL host: " + str); |
| 287 | } |
| 288 | String scheme = uri.getScheme(); |
| 289 | if (scheme != null && !scheme.equals("rmi")) { |
| 290 | throw new MalformedURLException("invalid URL scheme: " + str); |
| 291 | } |
| 292 | |
| 293 | String name = uri.getPath(); |
| 294 | if (name != null) { |
| 295 | if (name.startsWith("/")) { |
| 296 | name = name.substring(1); |
| 297 | } |
| 298 | if (name.length() == 0) { |
| 299 | name = null; |
| 300 | } |
| 301 | } |
| 302 | |
| 303 | String host = uri.getHost(); |
| 304 | if (host == null) { |
| 305 | host = ""; |
| 306 | try { |
| 307 | /* |
| 308 | * With 2396 URI handling, forms such as 'rmi://host:bar' |
| 309 | * or 'rmi://:<port>' are parsed into a registry based |
| 310 | * authority. We only want to allow server based naming |
| 311 | * authorities. |
| 312 | */ |
| 313 | uri.parseServerAuthority(); |
| 314 | } catch (URISyntaxException use) { |
| 315 | // Check if the authority is of form ':<port>' |
| 316 | String authority = uri.getAuthority(); |
| 317 | if (authority != null && authority.startsWith(":")) { |
| 318 | // Convert the authority to 'localhost:<port>' form |
| 319 | authority = "localhost" + authority; |
| 320 | try { |
| 321 | uri = new URI(null, authority, null, null, null); |
| 322 | // Make sure it now parses to a valid server based |
| 323 | // naming authority |
| 324 | uri.parseServerAuthority(); |
| 325 | } catch (URISyntaxException use2) { |
| 326 | throw new |
| 327 | MalformedURLException("invalid authority: " + str); |
| 328 | } |
| 329 | } else { |
| 330 | throw new |
| 331 | MalformedURLException("invalid authority: " + str); |
| 332 | } |
| 333 | } |
| 334 | } |
| 335 | int port = uri.getPort(); |
| 336 | if (port == -1) { |
| 337 | port = Registry.REGISTRY_PORT; |
| 338 | } |
| 339 | return new ParsedNamingURL(host, port, name); |
| 340 | } |
| 341 | |
| 342 | /** |
| 343 | * Simple class to enable multiple URL return values. |
| 344 | */ |
| 345 | private static class ParsedNamingURL { |
| 346 | String host; |
| 347 | int port; |
| 348 | String name; |
| 349 | |
| 350 | ParsedNamingURL(String host, int port, String name) { |
| 351 | this.host = host; |
| 352 | this.port = port; |
| 353 | this.name = name; |
| 354 | } |
| 355 | } |
| 356 | } |