Java tutorial
/* * ==================================================================== * 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. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.http.impl.client; import java.security.Principal; import javax.net.ssl.SSLSession; import org.apache.http.HttpConnection; import org.apache.http.annotation.Immutable; import org.apache.http.auth.AuthScheme; import org.apache.http.auth.AuthState; import org.apache.http.auth.Credentials; import org.apache.http.client.UserTokenHandler; import org.apache.http.client.protocol.HttpClientContext; import org.apache.http.conn.ManagedHttpClientConnection; import org.apache.http.protocol.HttpContext; /** * Default implementation of {@link UserTokenHandler}. This class will use * an instance of {@link Principal} as a state object for HTTP connections, * if it can be obtained from the given execution context. This helps ensure * persistent connections created with a particular user identity within * a particular security context can be reused by the same user only. * <p> * DefaultUserTokenHandler will use the user principle of connection * based authentication schemes such as NTLM or that of the SSL session * with the client authentication turned on. If both are unavailable, * <code>null</code> token will be returned. * * @since 4.0 */ @Immutable public class DefaultUserTokenHandler implements UserTokenHandler { public static final DefaultUserTokenHandler INSTANCE = new DefaultUserTokenHandler(); public Object getUserToken(final HttpContext context) { final HttpClientContext clientContext = HttpClientContext.adapt(context); Principal userPrincipal = null; final AuthState targetAuthState = clientContext.getTargetAuthState(); if (targetAuthState != null) { userPrincipal = getAuthPrincipal(targetAuthState); if (userPrincipal == null) { final AuthState proxyAuthState = clientContext.getProxyAuthState(); userPrincipal = getAuthPrincipal(proxyAuthState); } } if (userPrincipal == null) { final HttpConnection conn = clientContext.getConnection(); if (conn.isOpen() && conn instanceof ManagedHttpClientConnection) { final SSLSession sslsession = ((ManagedHttpClientConnection) conn).getSSLSession(); if (sslsession != null) { userPrincipal = sslsession.getLocalPrincipal(); } } } return userPrincipal; } private static Principal getAuthPrincipal(final AuthState authState) { final AuthScheme scheme = authState.getAuthScheme(); if (scheme != null && scheme.isComplete() && scheme.isConnectionBased()) { final Credentials creds = authState.getCredentials(); if (creds != null) { return creds.getUserPrincipal(); } } return null; } }