Java example source code file (DefaultUserTokenHandler.java)

This example source code file (DefaultUserTokenHandler.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java tags/keywords

authscheme, authstate, credentials, defaultusertokenhandler, httpcontext, immutable, managedclientconnection, net, object, principal, security, ssl, sslsession, usertokenhandler

The DefaultUserTokenHandler.java example source code

/*
 * ====================================================================
 *
 *  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.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.ClientContext;
import org.apache.http.conn.ManagedClientConnection;
import org.apache.http.protocol.ExecutionContext;
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 token will be returned.   
 *
 * @since 4.0
 */
@Immutable
public class DefaultUserTokenHandler implements UserTokenHandler {

    public Object getUserToken(final HttpContext context) {
        
        Principal userPrincipal = null;
        
        AuthState targetAuthState = (AuthState) context.getAttribute(
                ClientContext.TARGET_AUTH_STATE);
        if (targetAuthState != null) {
            userPrincipal = getAuthPrincipal(targetAuthState);
            if (userPrincipal == null) {
                AuthState proxyAuthState = (AuthState) context.getAttribute(
                        ClientContext.PROXY_AUTH_STATE);
                userPrincipal = getAuthPrincipal(proxyAuthState);
            }
        }
        
        if (userPrincipal == null) {
            ManagedClientConnection conn = (ManagedClientConnection) context.getAttribute(
                    ExecutionContext.HTTP_CONNECTION);
            if (conn.isOpen()) {
                SSLSession sslsession = conn.getSSLSession();
                if (sslsession != null) {
                    userPrincipal = sslsession.getLocalPrincipal();
                }
            }
        }
        
        return userPrincipal;
    }

    private static Principal getAuthPrincipal(final AuthState authState) {
        AuthScheme scheme = authState.getAuthScheme();
        if (scheme != null && scheme.isComplete() && scheme.isConnectionBased()) {
            Credentials creds = authState.getCredentials();
            if (creds != null) {
                return creds.getUserPrincipal(); 
            }
        }
        return null;
    }
    
}