J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1997-2005 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 | |
| 26 | package java.rmi.activation; |
| 27 | |
| 28 | import java.io.IOException; |
| 29 | import java.io.ObjectInputStream; |
| 30 | import java.io.Serializable; |
| 31 | import java.rmi.MarshalledObject; |
| 32 | import java.util.Arrays; |
| 33 | import java.util.Properties; |
| 34 | |
| 35 | /** |
| 36 | * An activation group descriptor contains the information necessary to |
| 37 | * create/recreate an activation group in which to activate objects. |
| 38 | * Such a descriptor contains: <ul> |
| 39 | * <li> the group's class name, |
| 40 | * <li> the group's code location (the location of the group's class), and |
| 41 | * <li> a "marshalled" object that can contain group specific |
| 42 | * initialization data. </ul> <p> |
| 43 | * |
| 44 | * The group's class must be a concrete subclass of |
| 45 | * <code>ActivationGroup</code>. A subclass of |
| 46 | * <code>ActivationGroup</code> is created/recreated via the |
| 47 | * <code>ActivationGroup.createGroup</code> static method that invokes |
| 48 | * a special constructor that takes two arguments: <ul> |
| 49 | * |
| 50 | * <li> the group's <code>ActivationGroupID</code>, and |
| 51 | * <li> the group's initialization data (in a |
| 52 | * <code>java.rmi.MarshalledObject</code>)</ul><p> |
| 53 | * |
| 54 | * @author Ann Wollrath |
| 55 | * @since 1.2 |
| 56 | * @see ActivationGroup |
| 57 | * @see ActivationGroupID |
| 58 | */ |
| 59 | public final class ActivationGroupDesc implements Serializable { |
| 60 | |
| 61 | /** |
| 62 | * @serial The group's fully package qualified class name. |
| 63 | */ |
| 64 | private String className; |
| 65 | |
| 66 | /** |
| 67 | * @serial The location from where to load the group's class. |
| 68 | */ |
| 69 | private String location; |
| 70 | |
| 71 | /** |
| 72 | * @serial The group's initialization data. |
| 73 | */ |
| 74 | private MarshalledObject<?> data; |
| 75 | |
| 76 | /** |
| 77 | * @serial The controlling options for executing the VM in |
| 78 | * another process. |
| 79 | */ |
| 80 | private CommandEnvironment env; |
| 81 | |
| 82 | /** |
| 83 | * @serial A properties map which will override those set |
| 84 | * by default in the subprocess environment. |
| 85 | */ |
| 86 | private Properties props; |
| 87 | |
| 88 | /** indicate compatibility with the Java 2 SDK v1.2 version of class */ |
| 89 | private static final long serialVersionUID = -4936225423168276595L; |
| 90 | |
| 91 | /** |
| 92 | * Constructs a group descriptor that uses the system defaults for group |
| 93 | * implementation and code location. Properties specify Java |
| 94 | * environment overrides (which will override system properties in |
| 95 | * the group implementation's VM). The command |
| 96 | * environment can control the exact command/options used in |
| 97 | * starting the child VM, or can be <code>null</code> to accept |
| 98 | * rmid's default. |
| 99 | * |
| 100 | * <p>This constructor will create an <code>ActivationGroupDesc</code> |
| 101 | * with a <code>null</code> group class name, which indicates the system's |
| 102 | * default <code>ActivationGroup</code> implementation. |
| 103 | * |
| 104 | * @param overrides the set of properties to set when the group is |
| 105 | * recreated. |
| 106 | * @param cmd the controlling options for executing the VM in |
| 107 | * another process (or <code>null</code>). |
| 108 | * @since 1.2 |
| 109 | */ |
| 110 | public ActivationGroupDesc(Properties overrides, |
| 111 | CommandEnvironment cmd) |
| 112 | { |
| 113 | this(null, null, null, overrides, cmd); |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * Specifies an alternate group implementation and execution |
| 118 | * environment to be used for the group. |
| 119 | * |
| 120 | * @param className the group's package qualified class name or |
| 121 | * <code>null</code>. A <code>null</code> group class name indicates |
| 122 | * the system's default <code>ActivationGroup</code> implementation. |
| 123 | * @param location the location from where to load the group's |
| 124 | * class |
| 125 | * @param data the group's initialization data contained in |
| 126 | * marshalled form (could contain properties, for example) |
| 127 | * @param overrides a properties map which will override those set |
| 128 | * by default in the subprocess environment (will be translated |
| 129 | * into <code>-D</code> options), or <code>null</code>. |
| 130 | * @param cmd the controlling options for executing the VM in |
| 131 | * another process (or <code>null</code>). |
| 132 | * @since 1.2 |
| 133 | */ |
| 134 | public ActivationGroupDesc(String className, |
| 135 | String location, |
| 136 | MarshalledObject<?> data, |
| 137 | Properties overrides, |
| 138 | CommandEnvironment cmd) |
| 139 | { |
| 140 | this.props = overrides; |
| 141 | this.env = cmd; |
| 142 | this.data = data; |
| 143 | this.location = location; |
| 144 | this.className = className; |
| 145 | } |
| 146 | |
| 147 | /** |
| 148 | * Returns the group's class name (possibly <code>null</code>). A |
| 149 | * <code>null</code> group class name indicates the system's default |
| 150 | * <code>ActivationGroup</code> implementation. |
| 151 | * @return the group's class name |
| 152 | * @since 1.2 |
| 153 | */ |
| 154 | public String getClassName() { |
| 155 | return className; |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Returns the group's code location. |
| 160 | * @return the group's code location |
| 161 | * @since 1.2 |
| 162 | */ |
| 163 | public String getLocation() { |
| 164 | return location; |
| 165 | } |
| 166 | |
| 167 | /** |
| 168 | * Returns the group's initialization data. |
| 169 | * @return the group's initialization data |
| 170 | * @since 1.2 |
| 171 | */ |
| 172 | public MarshalledObject<?> getData() { |
| 173 | return data; |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Returns the group's property-override list. |
| 178 | * @return the property-override list, or <code>null</code> |
| 179 | * @since 1.2 |
| 180 | */ |
| 181 | public Properties getPropertyOverrides() { |
| 182 | return (props != null) ? (Properties) props.clone() : null; |
| 183 | } |
| 184 | |
| 185 | /** |
| 186 | * Returns the group's command-environment control object. |
| 187 | * @return the command-environment object, or <code>null</code> |
| 188 | * @since 1.2 |
| 189 | */ |
| 190 | public CommandEnvironment getCommandEnvironment() { |
| 191 | return this.env; |
| 192 | } |
| 193 | |
| 194 | |
| 195 | /** |
| 196 | * Startup options for ActivationGroup implementations. |
| 197 | * |
| 198 | * This class allows overriding default system properties and |
| 199 | * specifying implementation-defined options for ActivationGroups. |
| 200 | * @since 1.2 |
| 201 | */ |
| 202 | public static class CommandEnvironment implements Serializable { |
| 203 | private static final long serialVersionUID = 6165754737887770191L; |
| 204 | |
| 205 | /** |
| 206 | * @serial |
| 207 | */ |
| 208 | private String command; |
| 209 | |
| 210 | /** |
| 211 | * @serial |
| 212 | */ |
| 213 | private String[] options; |
| 214 | |
| 215 | /** |
| 216 | * Create a CommandEnvironment with all the necessary |
| 217 | * information. |
| 218 | * |
| 219 | * @param cmdpath the name of the java executable, including |
| 220 | * the full path, or <code>null</code>, meaning "use rmid's default". |
| 221 | * The named program <em>must</em> be able to accept multiple |
| 222 | * <code>-Dpropname=value</code> options (as documented for the |
| 223 | * "java" tool) |
| 224 | * |
| 225 | * @param argv extra options which will be used in creating the |
| 226 | * ActivationGroup. Null has the same effect as an empty |
| 227 | * list. |
| 228 | * @since 1.2 |
| 229 | */ |
| 230 | public CommandEnvironment(String cmdpath, |
| 231 | String[] argv) |
| 232 | { |
| 233 | this.command = cmdpath; // might be null |
| 234 | |
| 235 | // Hold a safe copy of argv in this.options |
| 236 | if (argv == null) { |
| 237 | this.options = new String[0]; |
| 238 | } else { |
| 239 | this.options = new String[argv.length]; |
| 240 | System.arraycopy(argv, 0, this.options, 0, argv.length); |
| 241 | } |
| 242 | } |
| 243 | |
| 244 | /** |
| 245 | * Fetch the configured path-qualified java command name. |
| 246 | * |
| 247 | * @return the configured name, or <code>null</code> if configured to |
| 248 | * accept the default |
| 249 | * @since 1.2 |
| 250 | */ |
| 251 | public String getCommandPath() { |
| 252 | return (this.command); |
| 253 | } |
| 254 | |
| 255 | /** |
| 256 | * Fetch the configured java command options. |
| 257 | * |
| 258 | * @return An array of the command options which will be passed |
| 259 | * to the new child command by rmid. |
| 260 | * Note that rmid may add other options before or after these |
| 261 | * options, or both. |
| 262 | * Never returns <code>null</code>. |
| 263 | * @since 1.2 |
| 264 | */ |
| 265 | public String[] getCommandOptions() { |
| 266 | return (String[]) options.clone(); |
| 267 | } |
| 268 | |
| 269 | /** |
| 270 | * Compares two command environments for content equality. |
| 271 | * |
| 272 | * @param obj the Object to compare with |
| 273 | * @return true if these Objects are equal; false otherwise. |
| 274 | * @see java.util.Hashtable |
| 275 | * @since 1.2 |
| 276 | */ |
| 277 | public boolean equals(Object obj) { |
| 278 | |
| 279 | if (obj instanceof CommandEnvironment) { |
| 280 | CommandEnvironment env = (CommandEnvironment) obj; |
| 281 | return |
| 282 | ((command == null ? env.command == null : |
| 283 | command.equals(env.command)) && |
| 284 | Arrays.equals(options, env.options)); |
| 285 | } else { |
| 286 | return false; |
| 287 | } |
| 288 | } |
| 289 | |
| 290 | /** |
| 291 | * Return identical values for similar |
| 292 | * <code>CommandEnvironment</code>s. |
| 293 | * @return an integer |
| 294 | * @see java.util.Hashtable |
| 295 | */ |
| 296 | public int hashCode() |
| 297 | { |
| 298 | // hash command and ignore possibly expensive options |
| 299 | return (command == null ? 0 : command.hashCode()); |
| 300 | } |
| 301 | |
| 302 | /** |
| 303 | * <code>readObject</code> for custom serialization. |
| 304 | * |
| 305 | * <p>This method reads this object's serialized form for this |
| 306 | * class as follows: |
| 307 | * |
| 308 | * <p>This method first invokes <code>defaultReadObject</code> on |
| 309 | * the specified object input stream, and if <code>options</code> |
| 310 | * is <code>null</code>, then <code>options</code> is set to a |
| 311 | * zero-length array of <code>String</code>. |
| 312 | */ |
| 313 | private void readObject(ObjectInputStream in) |
| 314 | throws IOException, ClassNotFoundException |
| 315 | { |
| 316 | in.defaultReadObject(); |
| 317 | if (options == null) { |
| 318 | options = new String[0]; |
| 319 | } |
| 320 | } |
| 321 | } |
| 322 | |
| 323 | /** |
| 324 | * Compares two activation group descriptors for content equality. |
| 325 | * |
| 326 | * @param obj the Object to compare with |
| 327 | * @return true if these Objects are equal; false otherwise. |
| 328 | * @see java.util.Hashtable |
| 329 | * @since 1.2 |
| 330 | */ |
| 331 | public boolean equals(Object obj) { |
| 332 | |
| 333 | if (obj instanceof ActivationGroupDesc) { |
| 334 | ActivationGroupDesc desc = (ActivationGroupDesc) obj; |
| 335 | return |
| 336 | ((className == null ? desc.className == null : |
| 337 | className.equals(desc.className)) && |
| 338 | (location == null ? desc.location == null : |
| 339 | location.equals(desc.location)) && |
| 340 | (data == null ? desc.data == null : data.equals(desc.data)) && |
| 341 | (env == null ? desc.env == null : env.equals(desc.env)) && |
| 342 | (props == null ? desc.props == null : |
| 343 | props.equals(desc.props))); |
| 344 | } else { |
| 345 | return false; |
| 346 | } |
| 347 | } |
| 348 | |
| 349 | /** |
| 350 | * Produce identical numbers for similar <code>ActivationGroupDesc</code>s. |
| 351 | * @return an integer |
| 352 | * @see java.util.Hashtable |
| 353 | */ |
| 354 | public int hashCode() { |
| 355 | // hash location, className, data, and env |
| 356 | // but omit props (may be expensive) |
| 357 | return ((location == null |
| 358 | ? 0 |
| 359 | : location.hashCode() << 24) ^ |
| 360 | (env == null |
| 361 | ? 0 |
| 362 | : env.hashCode() << 16) ^ |
| 363 | (className == null |
| 364 | ? 0 |
| 365 | : className.hashCode() << 8) ^ |
| 366 | (data == null |
| 367 | ? 0 |
| 368 | : data.hashCode())); |
| 369 | } |
| 370 | } |