/*
 * Copyright 2005 the original author or authors.
 * 
 * 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.wamblee.security.servlet;

import javax.security.auth.Subject;

/**
 * Used for obtaining the authenticated subject in an application server. 
 */
public interface SubjectLocator {

    /**
     * Obtains the subject. 
     * @return Subject or null if no subject can be found. 
     */
    Subject getSubject(); 
}