/*
* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.security.core;
import java.io.Serializable;
import org.springframework.security.access.AccessDecisionManager;
/**
* Represents an authority granted to an {@link Authentication} object.
*
* <p>
* A <code>GrantedAuthority</code> must either represent itself as a <code>String</code>
* or be specifically supported by an {@link AccessDecisionManager}.
*
* @author Ben Alex
*/
public interface GrantedAuthority extends Serializable {
// ~ Methods
// ========================================================================================================
/**
* If the <code>GrantedAuthority</code> can be represented as a <code>String</code>
* and that <code>String</code> is sufficient in precision to be relied upon for an
* access control decision by an {@link AccessDecisionManager} (or delegate), this
* method should return such a <code>String</code>.
* <p>
* If the <code>GrantedAuthority</code> cannot be expressed with sufficient precision
* as a <code>String</code>, <code>null</code> should be returned. Returning
* <code>null</code> will require an <code>AccessDecisionManager</code> (or delegate)
* to specifically support the <code>GrantedAuthority</code> implementation, so
* returning <code>null</code> should be avoided unless actually required.
*
* @return a representation of the granted authority (or <code>null</code> if the
* granted authority cannot be expressed as a <code>String</code> with sufficient
* precision).
*/
String getAuthority();
}