1 /* AclEntry.java -- An entry in an ACL list. 2 Copyright (C) 1998 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 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 models an entry in an access control list (ACL). Java 45 * ACL's consist of a list of entries, where each consists of a 46 * <code>Principal</code> and a list of <code>Permission</code>'s which 47 * have been granted to that <code>Principal</code>. An ACL can also 48 * be <em>negative</em>, which indicates that the list of 49 * <code>Permission</code>'s is a list of permissions that are <em>not</em> 50 * granted to the <code>Principal</code>. A <code>Principal</code> can 51 * have at most one regular (or positive) ACL entry and one negative 52 * ACL entry. 53 * 54 * @version 0.0 55 * 56 * @author Aaron M. Renn (arenn@urbanophile.com) 57 */ 58 public interface AclEntry extends Cloneable 59 { 60 /** 61 * This method returns the <code>Principal</code> associated with this 62 * ACL entry. 63 * 64 * @return The <code>Principal</code> for this ACL entry 65 */ getPrincipal()66 Principal getPrincipal(); 67 68 /** 69 * This method sets ths <code>Principal</code> associated with this 70 * ACL entry. This operation will only succeed if there is not already 71 * a <code>Principal</code> assigned. 72 * 73 * @param user The <code>Principal</code> for this ACL entry 74 * 75 * @return <code>true</code> if the <code>Principal</code> was successfully set or <code>false</code> if this entry already has a <code>Principal</code>. 76 */ setPrincipal(Principal user)77 boolean setPrincipal(Principal user); 78 79 /** 80 * This method sets this ACL entry to be a <em>negative</em> entry, indicating 81 * that it contains a list of permissions that are <em>not</em> granted 82 * to the entry's <code>Principal</code>. Note that there is no way to 83 * undo this operation. 84 */ setNegativePermissions()85 void setNegativePermissions(); 86 87 /** 88 * This method tests whether or not this ACL entry is a negative entry or not. 89 * 90 * @return <code>true</code> if this ACL entry is negative, <code>false</code> otherwise 91 */ isNegative()92 boolean isNegative(); 93 94 /** 95 * This method adds the specified permission to this ACL entry. 96 * 97 * @param perm The <code>Permission</code> to add 98 * 99 * @return <code>true</code> if the permission was added or <code>false</code> if it was already set for this entry 100 */ addPermission(Permission permission)101 boolean addPermission(Permission permission); 102 103 /** 104 * This method deletes the specified permission to this ACL entry. 105 * 106 * @param perm The <code>Permission</code> to delete from this ACL entry. 107 * 108 * @return <code>true</code> if the permission was successfully deleted or <code>false</code> if the permission was not part of this ACL to begin with 109 */ removePermission(Permission perm)110 boolean removePermission(Permission perm); 111 112 /** 113 * This method tests whether or not the specified permission is associated 114 * with this ACL entry. 115 * 116 * @param perm The <code>Permission</code> to test 117 * 118 * @return <code>true</code> if this permission is associated with this entry or <code>false</code> otherwise 119 */ checkPermission(Permission permission)120 boolean checkPermission(Permission permission); 121 122 /** 123 * This method returns a list of all <code>Permission</code> objects 124 * associated with this ACL entry as an <code>Enumeration</code>. 125 * 126 * @return A list of permissions for this ACL entry 127 */ permissions()128 Enumeration permissions(); 129 130 /** 131 * This method returns this object as a <code>String</code>. 132 * 133 * @return A <code>String</code> representation of this object 134 */ toString()135 String toString(); 136 137 /** 138 * This method returns a clone of this ACL entry 139 * 140 * @return A clone of this ACL entry 141 */ clone()142 Object clone(); 143 } 144