1 /* Acl.java -- An access control 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 * A Java access control list (ACL) is a group of individual ACL entries. 45 * These entries consist of a <code>Principal</code> and a list of 46 * permissions this <code>Principal</code> is either granted or denied. 47 * A given <code>Principal</code> can have at most one positive ACL entry 48 * (i.e., one that grants permissions) and one negative ACL entry (i.e., one 49 * that denies permissions). If a given permission is both granted and 50 * denied, the ACL treats it as if it were never granted or denied. If 51 * both a <code>Principal</code> and a <code>Group</code> to which the 52 * <code>Principal</code> belongs have an ACL entry, the permissions for 53 * the individual <code>Principal</code> take precedence over the 54 * permissions of the <code>Group</code> if there is a conflict. 55 * <p> 56 * Additionally, the ACL interface extends the <code>Owner</code> interface 57 * and so an ACL has owners. Actions which modify the ACL are restricted 58 * to owners. 59 * 60 * @version 0.0 61 * 62 * @author Aaron M. Renn (arenn@urbanophile.com) 63 */ 64 public interface Acl extends Owner 65 { 66 67 /** 68 * This method returns the name of this ACL. 69 * 70 * @return The name of this ACL 71 */ getName()72 String getName(); 73 74 /** 75 * This method sets the name of the ACL 76 * 77 * @param caller The <code>Principal</code> requesting the action. 78 * @param name The new name for this ACL. 79 * 80 * @exception NotOwnerException If the caller is not an owner of this ACL. 81 */ setName(Principal caller, String name)82 void setName(Principal caller, String name) 83 throws NotOwnerException; 84 85 /** 86 * This method adds the specified entry to the ACL 87 * 88 * @param caller The <code>Principal</code> requesting the addition 89 * @param entry The ACL entry to add 90 * 91 * @return <code>true</code> if the entry was added, <code>false</code> 92 * if there is already an entry of the same type for the 93 * <code>Principal</code>. 94 * 95 * @exception NotOwnerException If the caller is not an owner of this ACL. 96 */ addEntry(Principal caller, AclEntry entry)97 boolean addEntry(Principal caller, AclEntry entry) 98 throws NotOwnerException; 99 100 /** 101 * This method delets the specified entry from the ACL 102 * 103 * @param caller The <code>Principal</code> requesting the deletion. 104 * @param entry The ACL entry to delete 105 * 106 * @return <code>true</code> if the entry was deleted, or <code>false</code> 107 * if this entry was not part of the ACL to begin with 108 * 109 * @exception NotOwnerException If the caller is not an owner of this ACL. 110 */ removeEntry(Principal caller, AclEntry entry)111 boolean removeEntry(Principal caller, AclEntry entry) 112 throws NotOwnerException; 113 114 /** 115 * This method returns a list of all the entries in the ACL as an 116 * <code>Enumeration</code>. 117 * 118 * @return An enumeration of the ACL entries 119 */ entries()120 Enumeration entries(); 121 122 /** 123 * This method tests whether or not the specified <code>Principal</code> 124 * has the specified <code>Permission</code> 125 * 126 * @param user The <code>Principal</code> to test 127 * @param perm The <code>Permission</code> to test for 128 * 129 * @return <code>true</code> if the user has been granted the permission, 130 * <code>false</code> otherwise 131 */ checkPermission(Principal user, Permission perm)132 boolean checkPermission(Principal user, Permission perm); 133 134 /** 135 * This method returns a list of <code>Permission</code>'s that are granted 136 * to a particular <code>Principal</code>. This includes any permissions 137 * that are granted to <code>Group</code>'s to which the <code>Principal</code> 138 * belongs unless they are overridden by a negative ACL. This permission 139 * list is returned as an <code>Enumeration</code>. 140 * 141 * @param user The <code>Principal</code> to retrieve permissions for. 142 * 143 * @return A list of permissions for the <code>Principal</code>. 144 */ getPermissions(Principal user)145 Enumeration getPermissions(Principal user); 146 147 /** 148 * This method returns the ACL as a <code>String</code> 149 * 150 * @return A <code>String</code> representation of this ACL 151 */ toString()152 String toString(); 153 } 154