core/src/main/java/org/apache/shiro/subject/PrincipalMap.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.apache.shiro.subject;

import java.util.Map;

/**
 * EXPERIMENTAL - DO NOT USE YET
 * <p/>
 * A {@code PrincipalMap} is map of all of a subject's principals - its identifying attributes like username, userId,
 * etc.
 * <p/>
 * The {@link Map} methods allow you to interact with a unified representation of
 * all of the Subject's principals, even if they came from different realms.  You can think of the {@code Map} methods
 * as the general purpose API for a Subject's principals.  That is, you can access a principal generally:
 * <pre>
 * Object principal = subject.getPrincipals().get(principalName);
 * </pre>
 * For example, to get the Subject's username (if the
 * username principal indeed exists and was populated by a Realm), you can do the following:
 * <pre>
 * String username = (String)subject.getPrincipals().get("username");
 * </pre>
 * <h3>Multi-Realm Environments</h3>
 * If your application uses multiple realms, the {@code Map} methods reflect
 * the the aggregate principals from <em>all</em> realms that authenticated the owning {@code Subject}.
 * <p/>
 * But in these multi-realm environments, it is often convenient or necessary to acquire only the principals contributed
 * by a specific realm (often in a realm implementation itself).  This {@code PrincipalMap} interface satisfies
 * those needs by providing additional realm-specific accessor/mutator methods.
 *
 * @author Les Hazlewood
 * @since 1.2
 */
public interface PrincipalMap extends PrincipalCollection, Map<String,Object> {

    Map<String,Object> getRealmPrincipals(String realmName);

    Map<String,Object> setRealmPrincipals(String realmName, Map<String,Object> principals);

    Object setRealmPrincipal(String realmName, String principalName, Object principal);

    Object getRealmPrincipal(String realmName, String realmPrincipal);

    Object removeRealmPrincipal(String realmName, String principalName);

}