httpclient调用工具类
日常工作中，经常会遇到一些需要调用http协议接口的情况，下面整理一个用apache的httpclient访问http的工具类：
package com.hx.imweb.utils;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.Map.Entry;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.HttpStatus;import org.apache.http.NameValuePair;import org.apache.http.client.entity.UrlEncodedFormEntity;import org.apache.http.client.methods.HttpPost;import org.apache.http.client.params.ClientPNames;import org.apache.http.client.params.CookiePolicy;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.message.BasicNameValuePair;import org.apache.http.params.HttpConnectionParams;import org.apache.http.protocol.HTTP;import org.apache.http.util.EntityUtils;import org.apache.log4j.Logger;import com.hx.imweb.service.ConfigParamLoadService;/** * * httpclient访问http接口的工具类 * * @author minux * */public class HttpClientUtils {public static final Logger logger = Logger.getLogger(HttpClientUtils.class);private static Map<String, String> headers = new HashMap<String, String>();static {headers.put("User-Agent","Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.1.2)");headers.put("Accept-Language", "zh-cn,zh;q=0.5");headers.put("Accept-Charset", "GB2312,utf-8;q=0.7,*;q=0.7");headers.put("Accept"," image/gif, image/x-xbitmap, image/jpeg, "+ "image/pjpeg, application/x-silverlight, application/vnd.ms-excel, "+ "application/vnd.ms-powerpoint, application/msword, application/x-shockwave-flash, */*");headers.put("Content-Type", "application/x-www-form-urlencoded");headers.put("Accept-Encoding", "gzip, deflate");}/** * 异常或者没拿到返回结果的情况下,result为"" * * @param url * @param param * @return */public static String httpPost(String url, Map<String, Object> param) {logger.info("httpPost URL [" + url + "] start ");DefaultHttpClient httpclient = null;HttpPost httpPost = null;HttpResponse response = null;HttpEntity entity = null;String result = "";StringBuffer suf = new StringBuffer();try {httpclient = new DefaultHttpClient();// 设置cookie的兼容性---考虑是否需要httpclient.getParams().setParameter(ClientPNames.COOKIE_POLICY,CookiePolicy.BROWSER_COMPATIBILITY);httpPost = new HttpPost(url);// 设置各种头信息for (Entry<String, String> entry : headers.entrySet()) {httpPost.setHeader(entry.getKey(), entry.getValue());}List<NameValuePair> nvps = new ArrayList<NameValuePair>();// 传入各种参数if (null != param) {for (Entry<String, Object> set : param.entrySet()) {String key = set.getKey();String value = set.getValue() == null ? "" : set.getValue().toString();nvps.add(new BasicNameValuePair(key, value));suf.append(" [" + key + "-" + value + "] ");}}logger.info("param " + suf.toString());httpPost.setEntity(new UrlEncodedFormEntity(nvps, HTTP.UTF_8));// 设置连接超时时间HttpConnectionParams.setConnectionTimeout(httpclient.getParams(),ConfigParamLoadService.httpConnectTimeOut);// 设置读数据超时时间HttpConnectionParams.setSoTimeout(httpPost.getParams(),ConfigParamLoadService.httpReadtimeOut);response = httpclient.execute(httpPost);int statusCode = response.getStatusLine().getStatusCode();if (statusCode != HttpStatus.SC_OK) {logger.error("HttpStatus ERROR" + "Method failed: "+ response.getStatusLine());return "";} else {entity = response.getEntity();if (null != entity) {byte[] bytes = EntityUtils.toByteArray(entity);result = new String(bytes, "UTF-8");} else {logger.error("httpPost URL [" + url+ "],httpEntity is null.");}return result;}} catch (Exception e) {logger.error("httpPost URL [" + url + "] error, ", e);return "";} finally {if (null != httpclient) {httpclient.getConnectionManager().shutdown();}logger.info("RESULT: [" + result + "]");logger.info("httpPost URL [" + url + "] end ");}}}?
该工具方法接受2个参数：
url--服务端提供访问的url地址
param--需要带上的参数
返回结果为：服务端设置的返回字符串(当然也可以是形如json之类的格式结果)
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用到的第三方jar有：
httpcore-4.2-beta1.jar
httpclient-4.2-beta1.jar
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另外工具类中引入了一个自己编写的service类ConfigParamLoadService
在这里只是传入了两个常量时间值（毫秒单位的超时时间值）
// 设置连接超时时间 HttpConnectionParams.setConnectionTimeout(httpclient.getParams(), ConfigParamLoadService.httpConnectTimeOut); // 设置读数据超时时间 HttpConnectionParams.setSoTimeout(httpPost.getParams(), ConfigParamLoadService.httpReadtimeOut);
??
jar包都可以到apache的官网下载