libjava/classpath/java/rmi/activation/ActivationDesc.java

   1 /* ActivationDesc.java -- record with info to activate an object
   2    Copyright (c) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38 package java.rmi.activation;
  39
  40 import java.io.Serializable;
  41 import java.rmi.MarshalledObject;
  42
  43 /**
  44  * Contains the information, necessary to activate the object. This information
  45  * includes:
  46  * <ul>
  47  * <li>the object class name</li>
  48  * <li>the object group identifier</li>
  49  * <li>the code location (codebase URL) that can be used to load the class
  50  * remotely</li>
  51  * <li>the object restart mode</li>
  52  * <li>the object specific intialization information</li>
  53  * </ul>
  54  *
  55  * @author Audrius Meskauskas (audriusa@bioinformatics.org) (from stub)
  56  */
  57 public final class ActivationDesc
  58     implements Serializable
  59 {
  60   /**
  61    * Use SVUID for interoperability.
  62    */
  63   static final long serialVersionUID = 7455834104417690957L;
  64
  65   /**
  66    * The group id.
  67    */
  68   private ActivationGroupID groupid;
  69
  70   /**
  71    * The class name.
  72    */
  73   private String classname;
  74
  75   /**
  76    * The code location URL.
  77    */
  78   private String location;
  79
  80   /**
  81    * The object specific intitalization data.
  82    */
  83   private MarshalledObject data;
  84
  85   /**
  86    * The start mode.
  87    */
  88   private boolean restart;
  89
  90   /**
  91    * Create the new activation description, assuming the object group is the
  92    * {@link ActivationGroup#currentGroupID()}.
  93    *
  94    * @param className the object fully qualified class name
  95    * @param location the code base URL
  96    * @param data the object initialization data, contained in a marshalled form
  97    */
  98   public ActivationDesc(String className, String location, MarshalledObject data)
  99       throws ActivationException
 100   {
 101     this(ActivationGroup.currentGroupID(), className, location, data, false);
 102   }
 103
 104   /**
 105    * Create the new activation description, assuming the object group is the
 106    * {@link ActivationGroup#currentGroupID()}.
 107    *
 108    * @param className the object fully qualified class name
 109    * @param location the code base URL
 110    * @param data the object initialization data, contained in a marshalled form
 111    * @param restart specifies reactivation mode after crash. If true, the object
 112    *          is activated when activator is restarted or the activation group
 113    *          is restarted. If false, the object is only activated on demand.
 114    *          This flag does has no effect during the normal operation (the
 115    *          object is normally activated on demand).
 116    */
 117   public ActivationDesc(String className, String location,
 118                         MarshalledObject data, boolean restart)
 119       throws ActivationException
 120   {
 121     this(ActivationGroup.currentGroupID(), className, location, data, restart);
 122   }
 123
 124   /**
 125    * Create the new activation description. Under crash, the object will only
 126    * be reactivated on demand.
 127    *
 128    * @param groupID the object group id.
 129    * @param className the object fully qualified class name
 130    * @param location the code base URL
 131    * @param data the object initialization data, contained in a marshalled form
 132    */
 133   public ActivationDesc(ActivationGroupID groupID, String className,
 134                         String location, MarshalledObject data)
 135   {
 136     this(groupID, className, location, data, false);
 137   }
 138
 139   /**
 140    * Create the new activation description, providing full information.
 141    *
 142    * @param groupID the object group id.
 143    * @param className the object fully qualified class name
 144    * @param location the code base URL
 145    * @param data the object initialization data, contained in a marshalled form
 146    * @param restart specifies reactivation mode after crash. If true, the object
 147    *          is activated when activator is restarted or the activation group
 148    *          is restarted. If false, the object is only activated on demand.
 149    *          This flag does has no effect during the normal operation (the
 150    *          object is normally activated on demand).
 151    */
 152   public ActivationDesc(ActivationGroupID groupID, String className,
 153                         String location, MarshalledObject data, boolean restart)
 154   {
 155     this.groupid = groupID;
 156     this.classname = className;
 157     this.location = location;
 158     this.data = data;
 159     this.restart = restart;
 160   }
 161
 162   public ActivationGroupID getGroupID()
 163   {
 164     return groupid;
 165   }
 166
 167   /**
 168    * Get the class name of the object being activated
 169    *
 170    * @return the fully qualified class name of the object being activated
 171    */
 172   public String getClassName()
 173   {
 174     return classname;
 175   }
 176
 177   /**
 178    * Get the code location URL ("codebase") of the object being activated.
 179    *
 180    * @return the codebase of the object being activated.
 181    */
 182   public String getLocation()
 183   {
 184     return location;
 185   }
 186
 187   public MarshalledObject getData()
 188   {
 189     return data;
 190   }
 191
 192   /**
 193    * Get the object reactivation strategy after crash.
 194    *
 195    * @return true ir the object is activated when activator is restarted or the
 196    *         activation group is restarted. False if the object is only
 197    *         activated on demand. This flag does has no effect during the normal
 198    *         operation (the object is normally activated on demand).
 199    */
 200   public boolean getRestartMode()
 201   {
 202     return restart;
 203   }
 204
 205   /**
 206    * Compare this object with another activation description for equality.
 207    *
 208    * @return true if all fields have the equal values, false otherwise.
 209    */
 210   public boolean equals(Object obj)
 211   {
 212     if (obj instanceof ActivationDesc)
 213       {
 214         ActivationDesc that = (ActivationDesc) obj;
 215         return eq(groupid, that.groupid) &&
 216                eq(classname, that.classname) &&
 217                eq(location, that.location) &&
 218                eq(data, that.data)
 219                && restart == that.restart;
 220       }
 221     else
 222       return false;
 223   }
 224
 225   /**
 226    * Get the hash code of this object (overridden to make the returned value
 227    * consistent with .equals(..).
 228    */
 229   public int hashCode()
 230   {
 231     return hash(groupid) ^ hash(classname) ^
 232       hash(location) ^ hash(data);
 233   }
 234
 235   /**
 236    * Get the hashcode of x or 0 if x == null.
 237    */
 238   static final int hash(Object x)
 239   {
 240     return x == null ? 0 : x.hashCode();
 241   }
 242
 243   /**
 244    * Compare by .equals if both a and b are not null, compare directly if at
 245    * least one of them is null.
 246    */
 247   static final boolean eq(Object a, Object b)
 248   {
 249     if (a == null || b == null)
 250       return a == b;
 251     else
 252       return a.equals(b);
 253   }
 254 }