/*
* Copyright (c) 1996, 2006, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.security.acl;
import java.util.*;
import java.io.*;
import java.security.Principal;
import java.security.acl.*;
/**
* This is a class that describes one entry that associates users
* or groups with permissions in the ACL.
* The entry may be used as a way of granting or denying permissions.
* @author Satish Dharmaraj
*/
public class AclEntryImpl implements AclEntry {
private Principal user = null;
private Vector<Permission> permissionSet = new Vector<Permission>(10, 10);
private boolean negative = false;
/**
* Construct an ACL entry that associates a user with permissions
* in the ACL.
* @param user The user that is associated with this entry.
*/
public AclEntryImpl(Principal user) {
this.user = user;
}
/**
* Construct a null ACL entry
*/
public AclEntryImpl() {
}
/**
* Sets the principal in the entity. If a group or a
* principal had already been set, a false value is
* returned, otherwise a true value is returned.
* @param user The user that is associated with this entry.
* @return true if the principal is set, false if there is
* one already.
*/
public boolean setPrincipal(Principal user) {
if (this.user != null)
return false;
this.user = user;
return true;
}
/**
* This method sets the ACL to have negative permissions.
* That is the user or group is denied the permission set
* specified in the entry.
*/
public void setNegativePermissions() {
negative = true;
}
/**
* Returns true if this is a negative ACL.
*/
public boolean isNegative() {
return negative;
}
/**
* A principal or a group can be associated with multiple
* permissions. This method adds a permission to the ACL entry.
* @param permission The permission to be associated with
* the principal or the group in the entry.
* @return true if the permission was added, false if the
* permission was already part of the permission set.
*/
public boolean addPermission(Permission permission) {
if (permissionSet.contains(permission))
return false;
permissionSet.addElement(permission);
return true;
}
/**
* The method disassociates the permission from the Principal
* or the Group in this ACL entry.
* @param permission The permission to be disassociated with
* the principal or the group in the entry.
* @return true if the permission is removed, false if the
* permission is not part of the permission set.
*/
public boolean removePermission(Permission permission) {
return permissionSet.removeElement(permission);
}
/**
* Checks if the passed permission is part of the allowed
* permission set in this entry.
* @param permission The permission that has to be part of
* the permission set in the entry.
* @return true if the permission passed is part of the
* permission set in the entry, false otherwise.
*/
public boolean checkPermission(Permission permission) {
return permissionSet.contains(permission);
}
/**
* return an enumeration of the permissions in this ACL entry.
*/
public Enumeration<Permission> permissions() {
return permissionSet.elements();
}
/**
* Return a string representation of the contents of the ACL entry.
*/
public String toString() {
StringBuffer s = new StringBuffer();
if (negative)
s.append("-");
else
s.append("+");
if (user instanceof Group)
s.append("Group.");
else
s.append("User.");
s.append(user + "=");
Enumeration<Permission> e = permissions();
while(e.hasMoreElements()) {
Permission p = e.nextElement();
s.append(p);
if (e.hasMoreElements())
s.append(",");
}
return new String(s);
}
/**
* Clones an AclEntry.
*/
public synchronized Object clone() {
AclEntryImpl cloned;
cloned = new AclEntryImpl(user);
cloned.permissionSet = (Vector<Permission>) permissionSet.clone();
cloned.negative = negative;
return cloned;
}
/**
* Return the Principal associated in this ACL entry.
* The method returns null if the entry uses a group
* instead of a principal.
*/
public Principal getPrincipal() {
return user;
}
}