org.openrdf.http.client.SesameClientImpl.java Source code

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Here is the source code for org.openrdf.http.client.SesameClientImpl.java

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/* 
 * Licensed to Aduna under one or more contributor license agreements.  
 * See the NOTICE.txt file distributed with this work for additional 
 * information regarding copyright ownership. 
 *
 * Aduna licenses this file to you under the terms of the Aduna BSD 
 * License (the "License"); you may not use this file except in compliance 
 * with the License. See the LICENSE.txt file distributed with this work 
 * for the full License.
 *
 * 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.openrdf.http.client;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

import org.apache.http.client.HttpClient;
import org.apache.http.client.utils.HttpClientUtils;
import org.apache.http.impl.client.StandardHttpRequestRetryHandler;
import org.apache.http.impl.client.SystemDefaultHttpClient;

/**
 * Uses {@link HttpClient} to manage HTTP connections.
 * 
 * @author James Leigh
 */
public class SesameClientImpl implements SesameClient {

    private HttpClient httpClient;

    private ExecutorService executor = null;

    /*--------------*
     * Constructors *
     *--------------*/

    public SesameClientImpl() {
        initialize();
    }

    /**
     * @return Returns the httpClient.
     */
    public synchronized HttpClient getHttpClient() {
        if (httpClient == null) {
            return httpClient = createHttpClient();
        }
        return httpClient;
    }

    /**
     * @param httpClient The httpClient to use for remote/service calls.
     */
    public synchronized void setHttpClient(HttpClient httpClient) {
        this.httpClient = httpClient;
    }

    private HttpClient createHttpClient() {
        SystemDefaultHttpClient client = new SystemDefaultHttpClient();
        client.setHttpRequestRetryHandler(new StandardHttpRequestRetryHandler(3, false));
        return client;
    }

    public synchronized SparqlSession createSparqlSession(String queryEndpointUrl, String updateEndpointUrl) {
        SparqlSession session = new SparqlSession(getHttpClient(), executor);
        session.setQueryURL(queryEndpointUrl);
        session.setUpdateURL(updateEndpointUrl);
        return session;
    }

    public synchronized SesameSession createSesameSession(String serverURL) {
        SesameSession session = new SesameSession(getHttpClient(), executor);
        session.setServerURL(serverURL);
        return session;
    }

    /*-----------------*
     * Get/set methods *
     *-----------------*/

    public synchronized void shutDown() {
        if (executor != null) {
            executor.shutdown();
            executor = null;
        }
        if (httpClient != null) {
            HttpClientUtils.closeQuietly(httpClient);
            httpClient = null;
        }
    }

    /**
     * (re)initializes the connection manager and HttpClient (if not already
     * done), for example after a shutdown has been invoked earlier. Invoking
     * this method multiple times will have no effect.
     */
    public synchronized void initialize() {
        if (executor == null) {
            executor = Executors.newCachedThreadPool();
        }
    }

}