使用ResponseHandler简化处理HTTP响应和释放相关资源的过程apachehttp客户端

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/** 来自 时代Java - N o w  J a v a . c o m**/

package org.apache.http.examples.client;


import java.io.IOException;


import org.apache.http.HttpEntity;

import org.apache.http.HttpResponse;

import org.apache.http.client.ClientProtocolException;

import org.apache.http.client.ResponseHandler;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.impl.client.CloseableHttpClient;

import org.apache.http.impl.client.HttpClients;

import org.apache.http.util.EntityUtils;
/** 时代Java - nowjava.com 提供 **/

/**

 * This example demonstrates the use of the {@link ResponseHandler} to simplify

 * the process of processing the HTTP response and releasing associated resources.

 */

public class ClientWithResponseHandler {


    public final static void main(String[] args) throws Exception {

        CloseableHttpClient httpclient = HttpClients.createDefault();

        try {

            HttpGet httpget = new HttpGet("http://localhost/");


            System.out.println("Executing request "

                    + httpget.getRequestLine());


            // Create a custom response handler

            ResponseHandler<String> responseHandler = new ResponseHandler<String>() {


                @Override

                public String handleResponse(final HttpResponse response)

                        throws ClientProtocolException, IOException {

                    int status = response.getStatusLine().getStatusCode();

                    if (status >= 200 && status < 300) {

                        HttpEntity entity = response.getEntity();

                        return entity != null ? EntityUtils

                                .toString(entity) : null;