1、HttpClient示例一、HttpClient簡介HttpClient 是 Apache Jakarta Common 下的子項目，用來提供高效的、最新的、功能豐富的支持 HTTP 協議的客戶端編程工具包，并且它支持 HTTP 協議最新的版本和建議。HttpClient 已經應用在很多的項目中，比如 Apache Jakarta 上很著名的另外兩個開源項目 Cactus 和 HTMLUnit 都使用了 HttpClient。現在HttpClient最新版本為 HttpClient 4.3.二、HttpClient特性基于標準,純凈的java語言.實現了Http1.0和Http1.1以可擴展的

2、面向對象的結構實現了Http全部的方法 (GET, POST, PUT, DELETE, HEAD, OPTIONS, and TRACE).支持HTTPS協議.通過Http代理建立透明的連接.利用CONNECT 方法通過Http代理建立隧道的https連接.Basic, Digest, NTLMv1, NTLMv2, NTLM2 Session, SNPNEGO/Kerberos 認證方案.插件式的自定義認證方案.便攜可靠的套接字工廠使它更容易的使用第三方解決方案.連接管理器支持多線程應用.支持設置最大連接數,同時支持設置每個主機的最大連接數.發現并關閉過期的連接.Automatic Coo

3、kie handling for reading Set-Cookie: headers from the server and sending them back out in a Cookie: header when appropriate.插件式的自定義Cookie策略.Request output streams to avoid buffering any content body by streaming directly to the socket to the server.Response input streams to efficiently read the resp

4、onse body by streaming directly from the socket to the server.在http1.0和http1.1中利用KeepAlive保持持久連接.直接獲取服務器發送的response code和 headers.設置連接超時的能力.實驗性的支持http1.1 response caching.源代碼基于Apache License 可免費獲取.三、詳細講解這里為了更好的理解，新建了一個java se的工程，如下圖所示 HttpClientTest類package com.yulore.httpproxy; import java.io.

5、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.Unrec

6、overableKeyException; import java.security.cert.CertificateException; import java.util.ArrayList; import java.util.List; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.NameValuePair; import org.apache.http.ParseException; import org.apache.http.client.

7、ClientProtocolException; import org.apache.http.client.HttpClient; 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.conn.scheme.Scheme; import org.apache.http.conn.ssl.SSLS

8、ocketFactory; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import org.apache.http.util.EntityUtils; import org.junit.Test; public class HttpClientTest Test public void jUnitTest() get(); /* * HttpClient連接SSL */ private void ssl() DefaultHtt

9、pClient httpclient = new DefaultHttpClient(); try KeyStore trustStore = KeyStore.getInstance(KeyStore .getDefaultType(); FileInputStream instream = new FileInputStream(new File( "d:tomcat.keystore"); try / 加載keyStore d:tomcat.keystore trustStore.load(instream, "123456".toCharArra

10、y(); catch (CertificateException e) e.printStackTrace(); finally try instream.close(); catch (Exception ignore) / 穿件Socket工廠,將trustStore注入 SSLSocketFactory socketFactory = new SSLSocketFactory(trustStore); / 創建Scheme Scheme sch = new Scheme("https", 8443, socketFactory); / 注冊Scheme httpcli

11、ent.getConnectionManager().getSchemeRegistry().register(sch); / 創建http請求(get方式) HttpGet httpget = new HttpGet( "https:/localhost:8443/myDemo/Ajax/serivceJ.action"); System.out.println("executing request" + httpget.getRequestLine(); HttpResponse response = httpclient.execute(httpg

12、et); HttpEntity entity = response.getEntity(); System.out.println("-"); System.out.println(response.getStatusLine(); if (entity != null) System.out.println("Response content length: " + entity.getContentLength(); String ss = EntityUtils.toString(entity); System.out.println(ss); E

13、ntityUtils.consume(entity); catch (ParseException e) e.printStackTrace(); catch (IOException e) e.printStackTrace(); catch (KeyManagementException e) e.printStackTrace(); catch (UnrecoverableKeyException e) e.printStackTrace(); catch (NoSuchAlgorithmException e) e.printStackTrace(); catch (KeyStoreE

14、xception e) e.printStackTrace(); finally httpclient.getConnectionManager().shutdown(); /* * post方式提交表單（模擬用戶登錄請求） */ private void postForm() / 創建默認的httpClient實例. HttpClient httpclient = new DefaultHttpClient(); / 創建httppost HttpPost httppost = new HttpPost( "http:/localhost:8080/myDemo/Ajax/seri

15、vceJ.action"); / 創建參數隊列 List<NameValuePair> formparams = new ArrayList<NameValuePair>(); formparams.add(new BasicNameValuePair("username", "admin"); formparams.add(new BasicNameValuePair("password", "123456"); UrlEncodedFormEntity uefEntity; t

16、ry uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8"); httppost.setEntity(uefEntity); System.out.println("executing request " + httppost.getURI(); HttpResponse response; response = httpclient.execute(httppost); HttpEntity entity = response.getEntity(); if (entity != null)

17、System.out.println("-"); System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8"); System.out.println("-"); catch (ClientProtocolException e) e.printStackTrace(); catch (UnsupportedEncodingException e1) e1.printStackTrace(); catch (IOExc

18、eption e) e.printStackTrace(); finally / 關閉連接,釋放資源 httpclient.getConnectionManager().shutdown(); /* * 發送 post請求訪問本地應用并根據傳遞參數不同返回不同結果 */ private void post() / 創建默認的httpClient實例. HttpClient httpclient = new DefaultHttpClient(); / 創建httppost HttpPost httppost = new HttpPost( "http:/localhost:8080/

19、myDemo/Ajax/serivceJ.action"); / 創建參數隊列 List<NameValuePair> formparams = new ArrayList<NameValuePair>(); formparams.add(new BasicNameValuePair("type", "house"); UrlEncodedFormEntity uefEntity; try uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8"

20、); httppost.setEntity(uefEntity); System.out.println("executing request " + httppost.getURI(); HttpResponse response; response = httpclient.execute(httppost); HttpEntity entity = response.getEntity(); if (entity != null) System.out.println("-"); System.out.println("Response

21、content: " + EntityUtils.toString(entity, "UTF-8"); System.out.println("-"); catch (ClientProtocolException e) e.printStackTrace(); catch (UnsupportedEncodingException e1) e1.printStackTrace(); catch (IOException e) e.printStackTrace(); finally / 關閉連接,釋放資源 httpclient.getConn

22、ectionManager().shutdown(); /* * 發送 get請求 */ private void get() HttpClient httpclient = new DefaultHttpClient(); try / 創建httpget. HttpGet httpget = new HttpGet(" System.out.println("executing request " + httpget.getURI(); / 執行get請求. HttpResponse response = httpclient.execute(httpget);

23、 / 獲取響應實體 HttpEntity entity = response.getEntity(); System.out.println("-"); / 打印響應狀態 System.out.println(response.getStatusLine(); if (entity != null) / 打印響應內容長度 System.out.println("Response content length: " + entity.getContentLength(); / 打印響應內容 System.out.println("Response

24、 content: " + EntityUtils.toString(entity); System.out.println("-"); catch (ClientProtocolException e) e.printStackTrace(); catch (ParseException e) e.printStackTrace(); catch (IOException e) e.printStackTrace(); finally / 關閉連接,釋放資源 httpclient.getConnectionManager().shutdown(); 詳細信息請看

25、程序中的注釋注意事項JUnit運行測試時報錯，錯誤日志信息如下：java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactoryat org.apache.http.impl.client.AbstractHttpClient.<init>(AbstractHttpClient.java:182)at org.apache.http.impl.client.DefaultHttpClient.<init>(DefaultHttpClient.java:150)at com.yulore.httpp

26、roxy.HttpClientTest.get(HttpClientTest.java:180)at com.yulore.httpproxy.HttpClientTest.jUnitTest(HttpClientTest.java:36)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)at sun.reflect.DelegatingMethodAccesso

27、rImpl.invoke(DelegatingMethodAccessorImpl.java:25)at java.lang.reflect.Method.invoke(Method.java:597)at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)at ernal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)at org.junit.runners.model

28、.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)at ernal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4Clas

29、sRunner.java:71)at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)at org.junit.runners.P