使用apache HttpClient发送Http请求

在平时的工作中，经常会使用Http去访问其他系统，此时一个Http的工具类就显得非常重要了。给大家分享一个简单的HttpClient的工具类，以备不时之需。

主要包括POST请求、GET请求和如何发送XML数据。

依赖的jar包如下：

<dependency>     <groupId>org.apache.httpcomponents</groupId>     <artifactId>httpclient</artifactId>     <version>4.3.6</version></dependency><dependency>     <groupId>org.apache.httpcomponents</groupId>     <artifactId>httpcore</artifactId>     <version>4.3.3</version></dependency><dependency>     <groupId>org.apache.httpcomponents</groupId>     <artifactId>fluent-hc</artifactId><pre name="code" class="html"><pre name="code" class="html"><pre name="code" class="html">     <version>4.3.6</version></dependency><dependency>     <groupId>dom4j</groupId>     <artifactId>dom4j</artifactId>     <version>1.6.1</version></dependency>

import java.io.IOException;import java.nio.charset.Charset;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import java.util.Map;import java.util.Map.Entry;import java.util.Set;import org.apache.http.HttpEntity;import org.apache.http.HttpStatus;import org.apache.http.client.config.RequestConfig;import org.apache.http.client.entity.UrlEncodedFormEntity;import org.apache.http.client.methods.CloseableHttpResponse;import org.apache.http.client.methods.HttpGet;import org.apache.http.client.methods.HttpPost;import org.apache.http.entity.StringEntity;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClients;import org.apache.http.message.BasicNameValuePair;import org.apache.http.util.EntityUtils;import org.dom4j.Document;import org.dom4j.DocumentHelper;import org.dom4j.Element;public class HttpClientManager {private static int connectionTimeout = 1000;// 连接超时时间,毫秒private static int soTimeout = 30000;// 读取数据超时时间，毫秒/** HttpClient对象 */private static CloseableHttpClient httpclient = HttpClients.custom().disableAutomaticRetries().build();/*** 超时设置 ****/private static RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(soTimeout).setConnectTimeout(connectionTimeout).build();//设置请求和传输超时时间/** * 根据给定的URL地址和参数字符串，以Get方法调用，如果成功返回true，如果失败返回false *  * @param url *            String url地址，不含参数 * @param param *            String 参数字符串，例如：a=1&b=2&c=3 */public String executeGetMethod(String url, String param) {String strResult = "";StringBuffer serverURL = new StringBuffer(url);if (param != null && param.length() > 0) {serverURL.append("?");serverURL.append(param);}HttpGet httpget = new HttpGet(serverURL.toString());httpget.setConfig(requestConfig);CloseableHttpResponse response=null;try {response = httpclient.execute(httpget);HttpEntity entity = response.getEntity();int iGetResultCode = response.getStatusLine().getStatusCode();if (iGetResultCode >= 200 && iGetResultCode < 303) {strResult = EntityUtils.toString(entity);} else if (iGetResultCode >= 400 && iGetResultCode < 500) {strResult = "请求的目标地址不存在：" + iGetResultCode;} else {strResult = "请求错误：" + iGetResultCode;}} catch (Exception ex) {ex.printStackTrace();} finally { try {if(response !=null){response.close();}} catch (Exception e) {e.printStackTrace();}}return strResult;}/** * 根据给定的URL地址和参数字符串，以Get方法调用，如果成功返回true，如果失败返回false *  * @param url *            String url地址，不含参数 * @param param *            Map<String, Object> 参数字表单 * @return boolean true－成功，false失败，如果返回成功可以getStrGetResponseBody() *         获取返回内容字符串，如果失败，则可访问getErrorInfo()获取错误提示。 */public String executePostMethod(String strURL, Map<String, String> param) {String strResult = "";HttpPost post = new HttpPost(strURL);post.setConfig(requestConfig);List<BasicNameValuePair> paraList = new ArrayList<BasicNameValuePair>(param.size());for (Entry<String, String> pEntry : param.entrySet()) {if(null != pEntry.getValue()){BasicNameValuePair nv = new BasicNameValuePair(pEntry.getKey(), pEntry.getValue());paraList.add(nv);}}//使用UTF-8UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paraList,Charset.forName("utf-8"));post.setEntity(entity);CloseableHttpResponse response=null;try {response = httpclient.execute(post);int iGetResultCode = response.getStatusLine().getStatusCode(); if (HttpStatus.SC_OK == iGetResultCode) {HttpEntity responseEntity = response.getEntity();strResult = EntityUtils.toString(responseEntity);}} catch (Exception ex) {ex.printStackTrace();} finally {try {if(response!=null){response.close();}} catch (IOException e) {}}return strResult;}/** * 发送xml数据 * @param strURL * @param params * @return */public String postByXml(String strURL,Map<String,String> params) {String strResult = "";CloseableHttpResponse response = null;try {HttpPost post = new HttpPost(strURL);post.setConfig(requestConfig);post.setHeader("Content-Type", "text/xml;charset=utf-8");String xmlData = convertMap2Xml(params);StringEntity se = new StringEntity(xmlData);post.setEntity(se);response = httpclient.execute(post);response = httpclient.execute(post);int iGetResultCode = response.getStatusLine().getStatusCode(); if (HttpStatus.SC_OK == iGetResultCode) {HttpEntity responseEntity = response.getEntity();strResult = EntityUtils.toString(responseEntity);}} catch (Exception e) {e.printStackTrace();} finally { try {if(response !=null){response.close();}} catch (Exception e) {e.printStackTrace();}}return strResult;}/** * 将map转换为xml * @param map */private static String convertMap2Xml(Map<String,String> map) {Set<Entry<String,String>> entrys = map.entrySet();Iterator<Entry<String,String>> iter = entrys.iterator();Document doc = DocumentHelper.createDocument();Element root = DocumentHelper.createElement("xml");while(iter.hasNext()) {Entry<String,String> entry = iter.next();Element key = DocumentHelper.createElement(entry.getKey());key.addCDATA(entry.getValue());root.add(key);}doc.add(root);return doc.asXML();}}

httpclient还支持使用代理的方式发送请求：

    String proxyHost = "127.0.0.1";//代理服务器地址信息            int proxyPort = 1080;//代理服务器端口            SystemDefaultCredentialsProvider credentialsProvider = new SystemDefaultCredentialsProvider();            credentialsProvider.setCredentials(new AuthScope(proxyHost, proxyPort), new UsernamePasswordCredentials("", ""));            CloseableHttpClient httpClient = HttpClientBuilder.create().setDefaultCredentialsProvider(credentialsProvider).build();            HttpHost proxy = new HttpHost(proxyHost, proxyPort);            RequestConfig config = RequestConfig.custom().setProxy(proxy).build();//设置代理信息            HttpGet getMethod = new HttpGet(strUrl);            getMethod.setConfig(config);            CloseableHttpResponse rsp = httpClient.execute(getMethod);            str = EntityUtils.toString(rsp.getEntity());