libjava/java/security/UnresolvedPermission.java

   1 /* UnresolvedPermission.java -- Placeholder for unresolved permissions.
   2    Copyright (C) 1998, 2001 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., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 As a special exception, if you link this library with other files to
  22 produce an executable, this library does not by itself cause the
  23 resulting executable to be covered by the GNU General Public License.
  24 This exception does not however invalidate any other reasons why the
  25 executable file might be covered by the GNU General Public License. */
  26
  27 package java.security;
  28
  29 import java.io.Serializable;
  30 // All uses of Certificate in this file refer to this class.
  31 import java.security.cert.Certificate;
  32
  33 /**
  34  * This class is used to hold instances of all permissions that cannot
  35  * be resolved to available permission classes when the security
  36  * <code>Policy</code> object is instantiated.  This may happen when the
  37  * necessary security class has not yet been downloaded from the network.
  38  * <p>
  39  * Instances of this class are re-resolved when <code>AccessController</code>
  40  * check is done.  At that time, a scan is made of all existing
  41  * <code>UnresolvedPermission</code> objects and they are converted to
  42  * objects of the appropriate permission type if the class for that type
  43  * is then available.
  44  *
  45  * @version 0.0
  46  *
  47  * @author Aaron M. Renn (arenn@urbanophile.com)
  48  */
  49 public final class UnresolvedPermission
  50   extends Permission
  51   implements Serializable
  52 {
  53
  54   /**
  55    * The list of actions associated with this permission object
  56    */
  57   private String actions;
  58
  59   /**
  60    * The list of <code>Certificates</code> associated with this object
  61    */
  62   private Certificate[] certs;
  63
  64   /**
  65    * The name of the class this object should be resolved to.
  66    */
  67   private String type;
  68
  69   /**
  70    * This method initializes a new instance of <code>UnresolvedPermission</code>
  71    * with all the information necessary to resolve it to an instance of the
  72    * proper class at a future time.
  73    *
  74    * @param type The name of the desired class this permission should be resolved to
  75    * @param name The name of this permission
  76    * @param actions The action list for this permission
  77    * @param certs The list of certificates this permission's class was signed with
  78    */
  79   public UnresolvedPermission(String type, String name, String actions,
  80                               Certificate[] certs)
  81   {
  82     super(name);
  83
  84     this.type = type;
  85     this.actions = actions;
  86     this.certs = certs;
  87   }
  88
  89   /**
  90    * This method returns the list of actions associated with this
  91    * permission.
  92    *
  93    * @return The action list
  94    */
  95   public String getActions()
  96   {
  97     return (actions);
  98   }
  99
 100   /**
 101    * This method returns <code>false</code> always to indicate that this
 102    * permission does not imply the specified permission.  An
 103    * <code>UnresolvedPermission</code> never grants any permissions.
 104    *
 105    * @param perm The <code>Permission</code> object to test against - ignored by this class
 106    *
 107    * @return <code>false</code> to indicate this permission does not imply the specified permission.
 108    */
 109   public boolean implies(Permission perm)
 110   {
 111     return (false);
 112   }
 113
 114   /**
 115    * This method tests this permission for equality against the specified
 116    * <code>Object</code>.  This will be true if and only if the following
 117    * conditions are met:
 118    * <p>
 119    * <ul>
 120    * <li>The specified <code>Object</code> is an instance of
 121    * <code>UnresolvedPermission</code>, or a subclass.
 122    * <li>The specified permission has the same type (i.e., desired class name)
 123    * as this permission.
 124    * <li>The specified permission has the same name as this one.
 125    * <li>The specified permissoin has the same action list as this one.
 126    * <li>The specified permission has the same certificate list as this one.
 127    * </ul>
 128    *
 129    * @param obj The <code>Object</code> to test for equality
 130    *
 131    * @return <code>true</code> if the specified object is equal to this one, <code>false</code> otherwise.
 132    */
 133   public boolean equals(Object obj)
 134   {
 135     if (!(obj instanceof UnresolvedPermission))
 136       return (false);
 137
 138     UnresolvedPermission up = (UnresolvedPermission) obj;
 139
 140     if (!getName().equals(up.getName()))
 141       return (false);
 142
 143     if (!getActions().equals(up.getActions()))
 144       return (false);
 145
 146     if (!type.equals(up.type))
 147       return (false);
 148
 149     if (!certs.equals(up.certs))
 150       return (false);
 151
 152     return (true);
 153   }
 154
 155   /**
 156    * Returns a hash code value for this object.
 157    *
 158    * @return A hash value
 159    */
 160   public int hashCode()
 161   {
 162     return (System.identityHashCode(this));
 163   }
 164
 165   /**
 166    * This method returns a <code>String</code> representation of this
 167    * class.  The format is: '(unresolved "ClassName "name" "actions")'
 168    *
 169    * @return A <code>String</code> representation of this object
 170    */
 171   public String toString()
 172   {
 173     return "(unresolved " + type + " " + getName() + " " + getActions() + ")";
 174   }
 175
 176   /**
 177    * This class returns a <code>PermissionCollection</code> object that can
 178    * be used to store instances of <code>UnresolvedPermission</code>.  If
 179    * <code>null</code> is returned, the caller is free to use any desired
 180    * <code>PermissionCollection</code>.
 181    *
 182    * @return A new <code>PermissionCollection</code>.
 183    */
 184   public PermissionCollection newPermissionCollection()
 185   {
 186     return (null);
 187   }
 188 }