博客
关于我
强烈建议你试试无所不能的chatGPT,快点击我
HttpClient使用详细教程
阅读量:4680 次
发布时间:2019-06-09

本文共 36957 字,大约阅读时间需要 123 分钟。

Http协议的重要性相信不用我多说了,HttpClient相比传统JDK自带的URLConnection,增加了易用性和灵活性(具体区别,日后我们再讨论),它不仅是客户端发送Http请求变得容易,而且也方便了开发人员测试接口(基于Http协议的),即提高了开发的效率,也方便提高代码的健壮性。因此熟练掌握HttpClient是很重要的必修内容,掌握HttpClient后,相信对于Http协议的了解会更加深入。

org.apache.commons.httpclient.HttpClient与org.apache.http.client.HttpClient的区别

Commons的HttpClient项目现在是生命的尽头,不再被开发,  已被Apache HttpComponents项目HttpClient和的HttpCore  模组取代,提供更好的性能和更大的灵活性。

一、简介

HttpClient是Apache Jakarta Common下的子项目,用来提供高效的、最新的、功能丰富的支持HTTP协议的客户端编程工具包,并且它支持HTTP协议最新的版本和建议。HttpClient已经应用在很多的项目中,比如Apache Jakarta上很著名的另外两个开源项目Cactus和HTMLUnit都使用了HttpClient。

下载地址: 

二、特性

1. 基于标准、纯净的java语言。实现了Http1.0和Http1.1

2. 以可扩展的面向对象的结构实现了Http全部的方法(GET, POST, PUT, DELETE, HEAD, OPTIONS, and TRACE)。

3. 支持HTTPS协议。

4. 通过Http代理建立透明的连接。

5. 利用CONNECT方法通过Http代理建立隧道的https连接。

6. Basic, Digest, NTLMv1, NTLMv2, NTLM2 Session, SNPNEGO/Kerberos认证方案。

7. 插件式的自定义认证方案。

8. 便携可靠的套接字工厂使它更容易的使用第三方解决方案。

9. 连接管理器支持多线程应用。支持设置最大连接数,同时支持设置每个主机的最大连接数,发现并关闭过期的连接。

10. 自动处理Set-Cookie中的Cookie。

11. 插件式的自定义Cookie策略。

12. Request的输出流可以避免流中内容直接缓冲到socket服务器。

13. Response的输入流可以有效的从socket服务器直接读取相应内容。

14. 在http1.0和http1.1中利用KeepAlive保持持久连接。

15. 直接获取服务器发送的response code和 headers。

16. 设置连接超时的能力。

17. 实验性的支持http1.1 response caching。

18. 源代码基于Apache License 可免费获取。

三、使用方法

使用HttpClient发送请求、接收响应很简单,一般需要如下几步即可。

1. 创建HttpClient对象。

2. 创建请求方法的实例,并指定请求URL。如果需要发送GET请求,创建HttpGet对象;如果需要发送POST请求,创建HttpPost对象。

3. 如果需要发送请求参数,可调用HttpGet、HttpPost共同的setParams(HetpParams params)方法来添加请求参数;对于HttpPost对象而言,也可调用setEntity(HttpEntity entity)方法来设置请求参数。

4. 调用HttpClient对象的execute(HttpUriRequest request)发送请求,该方法返回一个HttpResponse。

5. 调用HttpResponse的getAllHeaders()、getHeaders(String name)等方法可获取服务器的响应头;调用HttpResponse的getEntity()方法可获取HttpEntity对象,该对象包装了服务器的响应内容。程序可通过该对象获取服务器的响应内容。

6. 释放连接。无论执行方法是否成功,都必须释放连接

相关jar包
commons-cli-1.2.jar  commons-codec-1.9.jar  commons-logging-1.2.jar  fluent-hc-4.5.1.jar  httpclient-4.5.1.jar  httpclient-cache-4.5.1.jar  httpclient-win-4.5.1.jar  httpcore-4.4.3.jar  httpcore-ab-4.4.3.jar  httpcore-nio-4.4.3.jar  httpmime-4.5.1.jar  jna-4.1.0.jar  jna-platform-4.1.0.jar
最简单post请求, 源自 http://
package a; import java.io.FileInputStream;import java.io.IOException;import java.util.ArrayList;import java.util.List;import java.util.Properties; import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.NameValuePair;import org.apache.http.client.HttpClient;import org.apache.http.client.config.RequestConfig;import org.apache.http.client.entity.UrlEncodedFormEntity;import org.apache.http.client.methods.HttpPost;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.message.BasicNameValuePair;import org.apache.http.util.EntityUtils; public class First {    public static void main(String[] args) throws Exception{        List
formparams = new ArrayList
(); formparams.add(new BasicNameValuePair("account", "")); formparams.add(new BasicNameValuePair("password", "")); HttpEntity reqEntity = new UrlEncodedFormEntity(formparams, "utf-8"); RequestConfig requestConfig = RequestConfig.custom() .setConnectTimeout(5000)//一、连接超时:connectionTimeout-->指的是连接一个url的连接等待时间 .setSocketTimeout(5000)// 二、读取数据超时:SocketTimeout-->指的是连接上一个url,获取response的返回等待时间 .setConnectionRequestTimeout(5000) .build(); HttpClient client = new DefaultHttpClient(); HttpPost post = new HttpPost("http://cnivi.com.cn/login"); post.setEntity(reqEntity); post.setConfig(requestConfig); HttpResponse response = client.execute(post); if (response.getStatusLine().getStatusCode() == 200) { HttpEntity resEntity = response.getEntity(); String message = EntityUtils.toString(resEntity, "utf-8"); System.out.println(message); } else { System.out.println("请求失败"); } } }

四、实例

主文件

package com.test;    import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.security.KeyManagementException;import java.security.KeyStore;import java.security.KeyStoreException;import java.security.NoSuchAlgorithmException;import java.security.cert.CertificateException;import java.util.ArrayList;import java.util.List;import javax.net.ssl.SSLContext;import org.apache.http.HttpEntity;import org.apache.http.NameValuePair;import org.apache.http.ParseException;import org.apache.http.client.ClientProtocolException;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.conn.ssl.SSLConnectionSocketFactory;import org.apache.http.conn.ssl.SSLContexts;import org.apache.http.conn.ssl.TrustSelfSignedStrategy;import org.apache.http.entity.ContentType;import org.apache.http.entity.mime.MultipartEntityBuilder;import org.apache.http.entity.mime.content.FileBody;import org.apache.http.entity.mime.content.StringBody;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.apache.http.client.config.RequestConfig;import org.junit.Test;public class HttpClientTest {  //方法见下........}

HttpClientUtils工具类

package com.bobo.code.web.controller.technology.httpcomponents;  import org.apache.http.HttpEntity;import org.apache.http.HttpHost;import org.apache.http.HttpResponse;import org.apache.http.NameValuePair;import org.apache.http.client.HttpClient;import org.apache.http.client.config.RequestConfig;import org.apache.http.client.methods.HttpUriRequest;import org.apache.http.client.methods.RequestBuilder;import org.apache.http.conn.routing.HttpRoute;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClientBuilder;import org.apache.http.impl.client.HttpClients;import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;import org.apache.http.message.BasicNameValuePair;import org.apache.http.util.EntityUtils;  import java.io.IOException;import java.util.*;  public class HttpClientUtils {      private static PoolingHttpClientConnectionManager connectionManager = null;    private static HttpClientBuilder httpBuilder = null;    private static RequestConfig requestConfig = null;      private static int MAXCONNECTION = 10;      private static int DEFAULTMAXCONNECTION = 5;      private static String IP = "cnivi.com.cn";    private static int PORT = 80;      static {        //设置http的状态参数        requestConfig = RequestConfig.custom()                .setSocketTimeout(5000)                .setConnectTimeout(5000)                .setConnectionRequestTimeout(5000)                .build();          HttpHost target = new HttpHost(IP, PORT);        connectionManager = new PoolingHttpClientConnectionManager();        connectionManager.setMaxTotal(MAXCONNECTION);//客户端总并行链接最大数        connectionManager.setDefaultMaxPerRoute(DEFAULTMAXCONNECTION);//每个主机的最大并行链接数        connectionManager.setMaxPerRoute(new HttpRoute(target), 20);        httpBuilder = HttpClients.custom();        httpBuilder.setConnectionManager(connectionManager);    }      public static CloseableHttpClient getConnection() {        CloseableHttpClient httpClient = httpBuilder.build();        return httpClient;    }        public static HttpUriRequest getRequestMethod(Map
map, String url, String method) { List
params = new ArrayList
(); Set
> entrySet = map.entrySet(); for (Map.Entry
e : entrySet) { String name = e.getKey(); String value = e.getValue(); NameValuePair pair = new BasicNameValuePair(name, value); params.add(pair); } HttpUriRequest reqMethod = null; if ("post".equals(method)) { reqMethod = RequestBuilder.post().setUri(url) .addParameters(params.toArray(new BasicNameValuePair[params.size()])) .setConfig(requestConfig).build(); } else if ("get".equals(method)) { reqMethod = RequestBuilder.get().setUri(url) .addParameters(params.toArray(new BasicNameValuePair[params.size()])) .setConfig(requestConfig).build(); } return reqMethod; } public static void main(String args[]) throws IOException { Map
map = new HashMap
(); map.put("account", ""); map.put("password", ""); HttpClient client = getConnection(); HttpUriRequest post = getRequestMethod(map, "http://cnivi.com.cn/login", "post"); HttpResponse response = client.execute(post); if (response.getStatusLine().getStatusCode() == 200) { HttpEntity entity = response.getEntity(); String message = EntityUtils.toString(entity, "utf-8"); System.out.println(message); } else { System.out.println("请求失败"); } }}

get方式

/**     * 发送 get请求     */     public void get() {         CloseableHttpClient httpclient = HttpClients.createDefault();         try {             // 创建httpget.               HttpGet httpget = new HttpGet("http://www.baidu.com/");             System.out.println("executing request " + httpget.getURI());             // 执行get请求.               CloseableHttpResponse response = httpclient.execute(httpget);             try {                 // 获取响应实体                   HttpEntity entity = response.getEntity();                 System.out.println("--------------------------------------");                 // 打印响应状态                   System.out.println(response.getStatusLine());                 if (entity != null) {                     // 打印响应内容长度                       System.out.println("Response content length: " + entity.getContentLength());                     // 打印响应内容                       System.out.println("Response content: " + EntityUtils.toString(entity));                 }                 System.out.println("------------------------------------");             } finally {                 response.close();             }         } catch (ClientProtocolException e) {             e.printStackTrace();         } catch (ParseException e) {             e.printStackTrace();         } catch (IOException e) {             e.printStackTrace();         } finally {             // 关闭连接,释放资源               try {                 httpclient.close();             } catch (IOException e) {                 e.printStackTrace();             }         }     }

post方式

/**     * 发送 post请求访问本地应用并根据传递参数不同返回不同结果     */     public void post() {         // 创建默认的httpClient实例.           CloseableHttpClient httpclient = HttpClients.createDefault();         // 创建httppost           HttpPost httppost = new HttpPost("http://localhost:8080/myDemo/Ajax/serivceJ.action");         // 创建参数队列           List
formparams = new ArrayList
(); formparams.add(new BasicNameValuePair("type", "house")); UrlEncodedFormEntity uefEntity; try { uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8"); httppost.setEntity(uefEntity); System.out.println("executing request " + httppost.getURI()); CloseableHttpResponse response = httpclient.execute(httppost); try { HttpEntity entity = response.getEntity(); if (entity != null) { System.out.println("--------------------------------------"); System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8")); System.out.println("--------------------------------------"); } } finally { response.close(); } } catch (ClientProtocolException e) { e.printStackTrace(); } catch (UnsupportedEncodingException e1) { e1.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { // 关闭连接,释放资源 try { httpclient.close(); } catch (IOException e) { e.printStackTrace(); } } }

post方式乱码补充 

如果有乱码,可以偿试使用 StringEntity 来替换HttpEntity:

StringEntity content =new StringEntity(soapRequestData.toString(), Charset.forName("UTF-8"));// 第二个参数,设置后才会对,内容进行编码        content.setContentType("application/soap+xml; charset=UTF-8");        content.setContentEncoding("UTF-8");        httppost.setEntity(content);

具体SOAP协议代码如下:

package com.isoftstone.core.service.impl; import java.io.BufferedReader;import java.io.File;import java.io.FileInputStream;import java.io.FileReader;import java.io.IOException;import java.io.InputStreamReader;import java.nio.charset.Charset;import java.util.Scanner; import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.client.ClientProtocolException;import org.apache.http.client.HttpClient;import org.apache.http.client.entity.EntityBuilder;import org.apache.http.client.methods.HttpPost;import org.apache.http.entity.ContentType;import org.apache.http.entity.StringEntity;import org.apache.http.impl.client.HttpClients;import org.apache.http.util.EntityUtils;import org.apache.log4j.Logger;import org.jdom.Document;import org.jdom.Element; import com.isoftstone.core.common.constant.RequestConstants;import com.isoftstone.core.common.tools.XmlTool;import com.isoftstone.core.service.intf.ServiceOfStringPara;/** * 德勤定价系统,由核心主动调用 * @author King * */public class DeloittePricingSingleCarImpl implements ServiceOfStringPara {    private  String serviceUrl = "http://10.30.0.35:7001/ZSInsUW/Auto/PricingService";     private static Logger log = Logger.getLogger(DeloittePricingSingleCarImpl.class.getName());     public String invoke(String sRequest) {                StringBuffer soapRequestData = new StringBuffer();        soapRequestData.append("
"); soapRequestData.append("
"); soapRequestData.append("
"); soapRequestData.append("
"); soapRequestData.append("
"); soapRequestData.append(""); soapRequestData.append("
"); soapRequestData.append("
"); soapRequestData.append("
"); soapRequestData.append(""); HttpClient httpclient = HttpClients.createDefault(); HttpPost httppost = new HttpPost(serviceUrl); StringEntity content =new StringEntity(soapRequestData.toString(), Charset.forName("UTF-8"));// 第二个参数,设置后才会对,内容进行编码 content.setContentType("application/soap+xml; charset=UTF-8"); content.setContentEncoding("UTF-8"); httppost.setEntity(content); //用下面的服务器端以UTF-8接收到的报文会乱码,原因未知// HttpEntity reqEntity = EntityBuilder.create().setContentType(// ContentType.TEXT_PLAIN) // .TEXT_PLAIN// .setText(soapRequestData.toString()).build();// httppost.setEntity(reqEntity);// httppost.addHeader("Content-Type",// "application/soap+xml; charset=utf-8"); HttpResponse response = null; Document doc = null; String returnXml = null; String sentity = null; try { response = httpclient.execute(httppost); HttpEntity resEntity = response.getEntity(); if (resEntity != null) { sentity = EntityUtils.toString(resEntity, "UTF-8"); doc = XmlTool.getDocument(sentity, RequestConstants.ENCODE); System.out.println(doc.toString()); Element eRoot = doc.getRootElement(); Element body = eRoot.getChild("Body", eRoot.getNamespace()); Element resp = (Element) body.getChildren().get(0); Element returnele = resp.getChild("return"); returnXml = returnele.getText().toString(); } } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } finally { log.info("发送给德勤定价系统的请求报文:\n" + soapRequestData.toString()); log.info("德勤定价系统返回的响应报文:\n" + sentity); log.info("返回给核心的的报文:\n" + returnXml); } return returnXml; } public String getServiceUrl() { return serviceUrl; } public void setServiceUrl(String serviceUrl) { this.serviceUrl = serviceUrl; } public static void main(String[] args) throws Exception{ File file = new File("D:/浙商项目资料/z浙江资料/t唐建华/德勤定价调试报文.txt"); System.out.println(file.exists()); String temp2 = null; StringBuilder sb2 = new StringBuilder(); InputStreamReader isr = new InputStreamReader(new FileInputStream(file),"GBK"); BufferedReader br = new BufferedReader(isr); temp2 = br.readLine(); while( temp2 != null ){ sb2.append(temp2); temp2 = br.readLine(); } String sss = sb2.toString();// System.out.println(sss.toString()); new DeloittePricingSingleCarImpl().invoke(sss); }}

post提交表单

/**     * post方式提交表单(模拟用户登录请求)     */     public void postForm() {         // 创建默认的httpClient实例.           CloseableHttpClient httpclient = HttpClients.createDefault();         // 创建httppost           HttpPost httppost = new HttpPost("http://localhost:8080/myDemo/Ajax/serivceJ.action");         // 创建参数队列           List
formparams = new ArrayList
(); formparams.add(new BasicNameValuePair("username", "admin")); formparams.add(new BasicNameValuePair("password", "123456")); UrlEncodedFormEntity uefEntity; try { uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8"); httppost.setEntity(uefEntity); System.out.println("executing request " + httppost.getURI()); CloseableHttpResponse response = httpclient.execute(httppost); try { HttpEntity entity = response.getEntity(); if (entity != null) { System.out.println("--------------------------------------"); System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8")); System.out.println("--------------------------------------"); } } finally { response.close(); } } catch (ClientProtocolException e) { e.printStackTrace(); } catch (UnsupportedEncodingException e1) { e1.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { // 关闭连接,释放资源 try { httpclient.close(); } catch (IOException e) { e.printStackTrace(); } } }

文件上传

/**     * 上传文件     */     public void upload() {         CloseableHttpClient httpclient = HttpClients.createDefault();         try {             HttpPost httppost = new HttpPost("http://localhost:8080/myDemo/Ajax/serivceFile.action");                FileBody bin = new FileBody(new File("F:\\image\\sendpix0.jpg"));             StringBody comment = new StringBody("A binary file of some kind", ContentType.TEXT_PLAIN);                HttpEntity reqEntity = MultipartEntityBuilder.create().addPart("bin", bin).addPart("comment", comment).build();                httppost.setEntity(reqEntity);                System.out.println("executing request " + httppost.getRequestLine());             CloseableHttpResponse response = httpclient.execute(httppost);             try {                 System.out.println("----------------------------------------");                 System.out.println(response.getStatusLine());                 HttpEntity resEntity = response.getEntity();                 if (resEntity != null) {                     System.out.println("Response content length: " + resEntity.getContentLength());                 }                 EntityUtils.consume(resEntity);             } finally {                 response.close();             }         } catch (ClientProtocolException e) {             e.printStackTrace();         } catch (IOException e) {             e.printStackTrace();         } finally {             try {                 httpclient.close();             } catch (IOException e) {                 e.printStackTrace();             }         }     }

ssl连接

/**     * HttpClient连接SSL     */     public void ssl() {         CloseableHttpClient httpclient = null;         try {             KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());             FileInputStream instream = new FileInputStream(new File("d:\\tomcat.keystore"));             try {                 // 加载keyStore d:\\tomcat.keystore                   trustStore.load(instream, "123456".toCharArray());             } catch (CertificateException e) {                 e.printStackTrace();             } finally {                 try {                     instream.close();                 } catch (Exception ignore) {                 }             }             // 相信自己的CA和所有自签名的证书             SSLContext sslcontext = SSLContexts.custom().loadTrustMaterial(trustStore, new TrustSelfSignedStrategy()).build();             // 只允许使用TLSv1协议             SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslcontext, new String[] { "TLSv1" }, null,                     SSLConnectionSocketFactory.BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);             httpclient = HttpClients.custom().setSSLSocketFactory(sslsf).build();             // 创建http请求(get方式)             HttpGet httpget = new HttpGet("https://localhost:8443/myDemo/Ajax/serivceJ.action");             System.out.println("executing request" + httpget.getRequestLine());             CloseableHttpResponse response = httpclient.execute(httpget);             try {                 HttpEntity entity = response.getEntity();                 System.out.println("----------------------------------------");                 System.out.println(response.getStatusLine());                 if (entity != null) {                     System.out.println("Response content length: " + entity.getContentLength());                     System.out.println(EntityUtils.toString(entity));                     EntityUtils.consume(entity);                 }             } finally {                 response.close();             }         } catch (ParseException e) {             e.printStackTrace();         } catch (IOException e) {             e.printStackTrace();         } catch (KeyManagementException e) {             e.printStackTrace();         } catch (NoSuchAlgorithmException e) {             e.printStackTrace();         } catch (KeyStoreException e) {             e.printStackTrace();         } finally {             if (httpclient != null) {                 try {                     httpclient.close();                 } catch (IOException e) {                     e.printStackTrace();                 }             }         }     }

关于RequestConfig的配置:  

源自:  

public void requestConfig(){//      新建一个RequestConfig:        RequestConfig defaultRequestConfig = RequestConfig.custom()            //一、连接目标服务器超时时间:ConnectionTimeout-->指的是连接一个url的连接等待时间            .setConnectTimeout(5000)            //二、读取目标服务器数据超时时间:SocketTimeout-->指的是连接上一个url,获取response的返回等待时间            .setSocketTimeout(5000)            //三、从连接池获取连接的超时时间:ConnectionRequestTimeout            .setConnectionRequestTimeout(5000)            .build();         //      这个超时可以设置为客户端级别,作为所有请求的默认值:        CloseableHttpClient httpclient = HttpClients.custom()            .setDefaultRequestConfig(defaultRequestConfig)            .build();//       httpclient.execute(httppost);的时候可以让httppost直接享受到httpclient中的默认配置.         //      Request不会继承客户端级别的请求配置,所以在自定义Request的时候,需要将客户端的默认配置拷贝过去:        HttpGet httpget = new HttpGet("http://www.apache.org/");        RequestConfig requestConfig = RequestConfig.copy(defaultRequestConfig)            .setProxy(new HttpHost("myotherproxy", 8080))            .build();        httpget.setConfig(requestConfig);//      httpget可以单独地使用新copy的requestConfig请求配置,不会对别的request请求产生影响    }

httpGet或httpPost 的abort()和releaseConnection()差异

//httpPost.abort();//中断请求,接下来可以开始另一段请求,所以个人理应,用这个应该可以在session中虚拟登录 //httpPost.releaseConnection();//释放请求.如果释放了相当于要清空session

 根所以上差异,可知模拟登录可以如下:  源自 

package com.bms.core;   import java.io.IOException;import java.util.ArrayList;import java.util.List;   import org.apache.http.Consts;import org.apache.http.HttpEntity;import org.apache.http.HttpResponse;import org.apache.http.NameValuePair;import org.apache.http.client.ClientProtocolException;import org.apache.http.client.entity.UrlEncodedFormEntity;import org.apache.http.client.methods.HttpGet;import org.apache.http.client.methods.HttpPost;import org.apache.http.impl.client.DefaultHttpClient;import org.apache.http.message.BasicNameValuePair;import org.apache.http.util.EntityUtils;   import com.bms.util.CommonUtil;   public class Test2 {       /**     * @param args     * @throws IOException     * @throws ClientProtocolException     */    public static void main(String[] args) throws ClientProtocolException, IOException {        DefaultHttpClient httpclient = new DefaultHttpClient();            HttpGet httpGet = new HttpGet("http://www.baidu.com");         String body = "";         HttpResponse response;         HttpEntity entity;         response = httpclient.execute(httpGet);         entity = response.getEntity();         body = EntityUtils.toString(entity);//这个就是页面源码了         httpGet.abort();//中断请求,接下来可以开始另一段请求         System.out.println(body);         //httpGet.releaseConnection();//释放请求.如果释放了相当于要清空session         //以下是post方法         HttpPost httpPost = new HttpPost("http://www.baidu.com");//一定要改成可以提交的地址,这里用百度代替         List 
nvps = new ArrayList
(); nvps.add(new BasicNameValuePair("name", "1"));//名值对 nvps.add(new BasicNameValuePair("account", "xxxx")); httpPost.setEntity(new UrlEncodedFormEntity(nvps, Consts.UTF_8)); response = httpclient.execute(httpPost); entity = response.getEntity(); body = EntityUtils.toString(entity); System.out.println("Login form get: " + response.getStatusLine());//这个可以打印状态 httpPost.abort(); System.out.println(body); httpPost.releaseConnection(); } }

源自  

其它相关资料:

我项目中用到的HttpClientUtil (2016/12/17)

package com.isoftstone.pcis.isc.util; import java.io.IOException;import java.io.InterruptedIOException;import java.net.UnknownHostException; import javax.net.ssl.SSLException;import javax.net.ssl.SSLHandshakeException; import org.apache.http.HttpEntityEnclosingRequest;import org.apache.http.HttpRequest;import org.apache.http.NoHttpResponseException;import org.apache.http.client.HttpRequestRetryHandler;import org.apache.http.client.protocol.HttpClientContext;import org.apache.http.config.Registry;import org.apache.http.config.RegistryBuilder;import org.apache.http.conn.ConnectTimeoutException;import org.apache.http.conn.socket.ConnectionSocketFactory;import org.apache.http.conn.socket.LayeredConnectionSocketFactory;import org.apache.http.conn.socket.PlainConnectionSocketFactory;import org.apache.http.conn.ssl.SSLConnectionSocketFactory;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClients;import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;import org.apache.http.protocol.HttpContext;import com.isoftstone.pcis.isc.util.ProperUtil; public class HttpClientUtil {        private static CloseableHttpClient httpclient = null;         static final int maxTotal=Integer.valueOf(ProperUtil.get("maxTotal")).intValue();//总最大连接数    static final int defaultMaxPerRoute=Integer.valueOf(ProperUtil.get("corePoolSize")).intValue();//每条线路最大连接数 = 本系统核心线程数 , 这样永远不会超过最大连接         public static CloseableHttpClient getHttpClient() {                        if (null == httpclient) {                synchronized (HttpClientUtil.class) {                    if (null == httpclient) {                        httpclient = getNewHttpClient();                    }                }            }                        return httpclient;        }            private static CloseableHttpClient getNewHttpClient() {                       // 设置连接池            ConnectionSocketFactory plainsf = PlainConnectionSocketFactory.getSocketFactory();            LayeredConnectionSocketFactory sslsf = SSLConnectionSocketFactory.getSocketFactory();            Registry
registry = RegistryBuilder.
create().register("http", plainsf).register("https", sslsf).build(); PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager(registry); // 配置最大连接数 cm.setMaxTotal(maxTotal); // 配置每条线路的最大连接数 cm.setDefaultMaxPerRoute(defaultMaxPerRoute); // 请求重试处理 HttpRequestRetryHandler httpRequestRetryHandler = new HttpRequestRetryHandler() { @Override public boolean retryRequest(IOException exception, int executionCount, HttpContext context) { if (executionCount >= 2) {
// 如果已经重试了2次,就放弃 return false; } if (exception instanceof NoHttpResponseException) {
// 如果服务器丢掉了连接,那么就重试 return true; } if (exception instanceof SSLHandshakeException) {
// 不要重试SSL握手异常 return false; } if (exception instanceof InterruptedIOException) {
// 超时 return false; } if (exception instanceof UnknownHostException) {
// 目标服务器不可达 return false; } if (exception instanceof ConnectTimeoutException) {
// 连接被拒绝 return false; } if (exception instanceof SSLException) {
// SSL握手异常 return false; } HttpClientContext clientContext = HttpClientContext.adapt(context); HttpRequest request = clientContext.getRequest(); if (!(request instanceof HttpEntityEnclosingRequest)) { return true; } return false; } }; CloseableHttpClient newHttpclient=null; newHttpclient = HttpClients.custom() .setConnectionManager(cm)// .setDefaultRequestConfig(requestConfig) .setRetryHandler(httpRequestRetryHandler) .build(); return newHttpclient; }}

我自己整理的HttpClientTool (2017/06/01)

package com.isoftstone.core.util; import java.io.IOException;import java.io.InterruptedIOException;import java.net.UnknownHostException; import javax.net.ssl.SSLException;import javax.net.ssl.SSLHandshakeException; import org.apache.http.HttpEntityEnclosingRequest;import org.apache.http.HttpHost;import org.apache.http.HttpRequest;import org.apache.http.NoHttpResponseException;import org.apache.http.client.HttpRequestRetryHandler;import org.apache.http.client.config.RequestConfig;import org.apache.http.client.protocol.HttpClientContext;import org.apache.http.config.Registry;import org.apache.http.config.RegistryBuilder;import org.apache.http.conn.ConnectTimeoutException;import org.apache.http.conn.routing.HttpRoute;import org.apache.http.conn.socket.ConnectionSocketFactory;import org.apache.http.conn.socket.LayeredConnectionSocketFactory;import org.apache.http.conn.socket.PlainConnectionSocketFactory;import org.apache.http.conn.ssl.SSLConnectionSocketFactory;import org.apache.http.impl.client.CloseableHttpClient;import org.apache.http.impl.client.HttpClients;import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;import org.apache.http.protocol.HttpContext; /** * org.apache.http.impl.client.CloseableHttpClient链接池生成工具 * @reference http://www.cnblogs.com/whatlonelytear/articles/4835538.html * @author King * @date 20170601 */public class HttpClientTool {     // org.apache.http.impl.client.CloseableHttpClient    private static CloseableHttpClient httpclient = null;     // 这里就直接默认固定了,因为以下三个参数在新建的method中仍然可以重新配置并被覆盖.    static final int connectionRequestTimeout = 5000;// ms毫秒,从池中获取链接超时时间    static final int connectTimeout = 5000;// ms毫秒,建立链接超时时间    static final int socketTimeout = 30000;// ms毫秒,读取超时时间     // 总配置,主要涉及是以下两个参数,如果要作调整没有用到properties会比较后麻烦,但鉴于一经粘贴,随处可用的特点,就不再做依赖性配置化处理了.    // 而且这个参数同一家公司基本不会变动.    static final int maxTotal = 500;// 最大总并发,很重要的参数    static final int maxPerRoute = 100;// 每路并发,很重要的参数     // 正常情况这里应该配成MAP或LIST    // 细化配置参数,用来对每路参数做精细化处理,可以管控各ip的流量,比如默认配置请求baidu:80端口最大100个并发链接,    static final String detailHostName = "http://www.baidu.com";// 每个细化配置之ip(不重要,在特殊场景很有用)    static final int detailPort = 80;// 每个细化配置之port(不重要,在特殊场景很有用)    static final int detailMaxPerRoute = 100;// 每个细化配置之最大并发数(不重要,在特殊场景很有用)     public static CloseableHttpClient getHttpClient() {        if (null == httpclient) {            synchronized (HttpClientTool.class) {                if (null == httpclient) {                    httpclient = init();                }            }        }        return httpclient;    }     /**     * 链接池初始化 这里最重要的一点理解就是. 让CloseableHttpClient 一直活在池的世界里, 但是HttpPost却一直用完就消掉.     * 这样可以让链接一直保持着.     *      * @return     */    private static CloseableHttpClient init() {        CloseableHttpClient newHttpclient = null;         // 设置连接池        ConnectionSocketFactory plainsf = PlainConnectionSocketFactory.getSocketFactory();        LayeredConnectionSocketFactory sslsf = SSLConnectionSocketFactory.getSocketFactory();        Registry
registry = RegistryBuilder.
create().register("http", plainsf).register("https", sslsf).build(); PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager(registry); // 将最大连接数增加 cm.setMaxTotal(maxTotal); // 将每个路由基础的连接增加 cm.setDefaultMaxPerRoute(maxPerRoute); // 细化配置开始,其实这里用Map或List的for循环来配置每个链接,在特殊场景很有用. // 将每个路由基础的连接做特殊化配置,一般用不着 HttpHost httpHost = new HttpHost(detailHostName, detailPort); // 将目标主机的最大连接数增加 cm.setMaxPerRoute(new HttpRoute(httpHost), detailMaxPerRoute); // cm.setMaxPerRoute(new HttpRoute(httpHost2), // detailMaxPerRoute2);//可以有细化配置2 // cm.setMaxPerRoute(new HttpRoute(httpHost3), // detailMaxPerRoute3);//可以有细化配置3 // 细化配置结束 // 请求重试处理 HttpRequestRetryHandler httpRequestRetryHandler = new HttpRequestRetryHandler() { @Override public boolean retryRequest(IOException exception, int executionCount, HttpContext context) { if (executionCount >= 2) {
// 如果已经重试了2次,就放弃 return false; } if (exception instanceof NoHttpResponseException) {
// 如果服务器丢掉了连接,那么就重试 return true; } if (exception instanceof SSLHandshakeException) {
// 不要重试SSL握手异常 return false; } if (exception instanceof InterruptedIOException) {
// 超时 return false; } if (exception instanceof UnknownHostException) {
// 目标服务器不可达 return false; } if (exception instanceof ConnectTimeoutException) {
// 连接被拒绝 return false; } if (exception instanceof SSLException) {
// SSL握手异常 return false; } HttpClientContext clientContext = HttpClientContext.adapt(context); HttpRequest request = clientContext.getRequest(); // 如果请求是幂等的,就再次尝试 if (!(request instanceof HttpEntityEnclosingRequest)) { return true; } return false; } }; // 配置请求的超时设置 RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(connectionRequestTimeout).setConnectTimeout(connectTimeout).setSocketTimeout(socketTimeout).build(); newHttpclient = HttpClients.custom().setConnectionManager(cm).setDefaultRequestConfig(requestConfig).setRetryHandler(httpRequestRetryHandler).build(); return newHttpclient; }}

异常列表

 

而服务端返回HTTP/1.1 404 Not Found 代表能连上主机,只是目标主机没有提供这个服务(请求的服务路径可能写错)

 

FROM:http://www.cnblogs.com/whatlonelytear/articles/4835538.html

 

转载于:https://www.cnblogs.com/jepson6669/p/9358244.html

你可能感兴趣的文章