gomp-20050608-branch/libjava/classpath/java/security/acl/Group.java

   1 /* Group.java -- Represents a group of Principals
   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., 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.security.acl;
  39
  40 import java.security.Principal;
  41 import java.util.Enumeration;
  42
  43 /**
  44  * This interface represents a group of <code>Principals</code>.  Note that
  45  * since this interface extends <code>Principal</code>, a <code>Group</code>
  46  * can be used where ever a <code>Principal</code> is requested.  This
  47  * includes arguments to the methods in this interface.
  48  *
  49  * @version 0.0
  50  *
  51  * @author Aaron M. Renn (arenn@urbanophile.com)
  52  */
  53 public interface Group extends Principal
  54 {
  55   /**
  56    * This method adds a new <code>Principal</code> to this group.
  57    *
  58    * @param user The new <code>Principal</code> to add
  59    *
  60    * @return <code>true</code> if the user was successfully added or <code>false</code> if the user is already a member
  61    */
  62   boolean addMember(Principal user);
  63
  64   /**
  65    * This method deletes a member from the group.
  66    *
  67    * @param user The <code>Principal</code> to delete
  68    *
  69    * @return <code>true</code> if the user was successfully deleted or <code>false</code> if the user is not a member of the group
  70    */
  71   boolean removeMember(Principal user);
  72
  73   /**
  74    * This method tests whether or not a given <code>Principal</code> is a
  75    * member of this group.
  76    *
  77    * @param user The <code>Principal</code> to test for membership
  78    *
  79    * @return <code>true</code> if the user is member, <code>false</code> otherwise
  80    */
  81   boolean isMember(Principal member);
  82
  83   /**
  84    * This method returns a list of all members of the group as an
  85    * <code>Enumeration</code>.
  86    *
  87    * @return The list of all members of the group
  88    */
  89   Enumeration members();
  90 }