HttpClient的相关例子

摘自 ：http://hi.baidu.com/kinsonhe/blog/item/4a77d411ff00288a6538db96.html

1、HttpClient使用GET方式通过代理服务器读取页面的例子

import java.io.BufferedReader;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.conn.params.ConnRoutePNames;
import org.apache.http.impl.client.DefaultHttpClient;

/**
* HttpClient使用GET方式通过代理服务器读取页面的例子。
* 
* @author JAVA世纪网(java2000.net, laozizhu.com)
*/
public class HttpClientGet {
public static void main(String[] args) throws Exception {
DefaultHttpClient httpclient = new DefaultHttpClient();
// 访问的目标站点，端口和协议
HttpHost targetHost = new HttpHost("www.java2000.net");
// 代理的设置
HttpHost proxy = new HttpHost("10.60.8.20", 8080);
httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
// 目标地址
HttpGet httpget = new HttpGet("/");
System.out.println("目标: " + targetHost);
System.out.println("请求: " + httpget.getRequestLine());
// 执行
HttpResponse response = httpclient.execute(targetHost, httpget);
HttpEntity entity = response.getEntity();
System.out.println("----------------------------------------");
System.out.println(response.getStatusLine());
if (entity != null) {
System.out.println("Response content length: " + entity.getContentLength());
}
// 显示结果
BufferedReader reader = new BufferedReader(new InputStreamReader(entity.getContent(), "UTF-8"));
String line = null;
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
if (entity != null) {
entity.consumeContent();
}
}
}

 2、HttpClient 4 使用POST方式提交普通表单数据的例子

import java.io.BufferedReader;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.params.ConnRoutePNames;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;

/**
* HttpClient 4 使用POST方式提交普通表单数据的例子.
* 
* @author JAVA世纪网(java2000.net, laozizhu.com)
*/
public class HttpClientPost {
public static void main(String[] args) throws Exception {
DefaultHttpClient httpclient = new DefaultHttpClient();
// 代理的设置
HttpHost proxy = new HttpHost("10.60.8.20", 8080);
httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
// 目标地址
HttpPost httppost = new HttpPost("http://www.java2000.net/login.jsp");
System.out.println("请求: " + httppost.getRequestLine());
// 构造最简单的字符串数据
StringEntity reqEntity = new StringEntity("username=test&password=test");
// 设置类型
reqEntity.setContentType("application/x-www-form-urlencoded");
// 设置请求的数据
httppost.setEntity(reqEntity);
// 执行
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
System.out.println("----------------------------------------");
System.out.println(response.getStatusLine());
if (entity != null) {
System.out.println("Response content length: " + entity.getContentLength());
}
// 显示结果
BufferedReader reader = new BufferedReader(new InputStreamReader(entity.getContent(), "UTF-8"));
String line = null;
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
if (entity != null) {
entity.consumeContent();
}
}
}

 3、HttpClient 4.0通过代理访问Https的代码例子

import java.io.BufferedReader;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.conn.params.ConnRoutePNames;
import org.apache.http.impl.client.DefaultHttpClient;

/**
* HttpClient 4.0通过代理访问Https的代码例子。
* 
* @author JAVA世纪网(java2000.net, laozizhu.com)
*/
public class HttpsProxyGet {
public static void main(String[] args) throws Exception {
DefaultHttpClient httpclient = new DefaultHttpClient();
// 认证的数据
// 我这里是瞎写的，请根据实际情况填写
httpclient.getCredentialsProvider().setCredentials(new AuthScope("10.60.8.20", 8080),
new UsernamePasswordCredentials("username", "password"));
// 访问的目标站点，端口和协议
HttpHost targetHost = new HttpHost("www.google.com", 443, "https");
// 代理的设置
HttpHost proxy = new HttpHost("10.60.8.20", 8080);
httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
// 目标地址
HttpGet httpget = new HttpGet("/adsense/login/zh_CN/?");
System.out.println("目标: " + targetHost);
System.out.println("请求: " + httpget.getRequestLine());
System.out.println("代理: " + proxy);
// 执行
HttpResponse response = httpclient.execute(targetHost, httpget);
HttpEntity entity = response.getEntity();
System.out.println("----------------------------------------");
System.out.println(response.getStatusLine());
if (entity != null) {
System.out.println("Response content length: " + entity.getContentLength());
}
// 显示结果
BufferedReader reader = new BufferedReader(new InputStreamReader(entity.getContent(), "UTF-8"));
String line = null;
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
if (entity != null) {
entity.consumeContent();
}
}
}

 4、HttpClient读取页面的使用例子

package com.laozizhu.apache.httpclient;

import java.net.Socket;

import org.apache.http.ConnectionReuseStrategy;
import org.apache.http.Header;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.HttpVersion;
import org.apache.http.impl.DefaultConnectionReuseStrategy;
import org.apache.http.impl.DefaultHttpClientConnection;
import org.apache.http.message.BasicHttpRequest;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpParams;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.BasicHttpProcessor;
import org.apache.http.protocol.ExecutionContext;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.HttpRequestExecutor;
import org.apache.http.protocol.RequestConnControl;
import org.apache.http.protocol.RequestContent;
import org.apache.http.protocol.RequestExpectContinue;
import org.apache.http.protocol.RequestTargetHost;
import org.apache.http.protocol.RequestUserAgent;
import org.apache.http.util.EntityUtils;

/**
* HttpClient读取页面的使用例子
* @author 老紫竹(java2000.net)
*
*/
public class HttpGet {
public static void main(String[] args) throws Exception {

    HttpParams params = new BasicHttpParams();
// HTTP 协议的版本,1.1/1.0/0.9
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
// 字符集
HttpProtocolParams.setContentCharset(params, "UTF-8");
// 伪装的浏览器类型
// IE7 是 
// Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 6.0)
//
// Firefox3.03
// Mozilla/5.0 (Windows; U; Windows NT 5.2; zh-CN; rv:1.9.0.3) Gecko/2008092417 Firefox/3.0.3
//
HttpProtocolParams.setUserAgent(params, "HttpComponents/1.1");
HttpProtocolParams.setUseExpectContinue(params, true);

    BasicHttpProcessor httpproc = new BasicHttpProcessor();

    httpproc.addInterceptor(new RequestContent());
httpproc.addInterceptor(new RequestTargetHost());

    httpproc.addInterceptor(new RequestConnControl());
httpproc.addInterceptor(new RequestUserAgent());
httpproc.addInterceptor(new RequestExpectContinue());

    HttpRequestExecutor httpexecutor = new HttpRequestExecutor();

    HttpContext context = new BasicHttpContext(null);
HttpHost host = new HttpHost("www.java2000.net", 80);

    DefaultHttpClientConnection conn = new DefaultHttpClientConnection();
ConnectionReuseStrategy connStrategy = new DefaultConnectionReuseStrategy();

    context.setAttribute(ExecutionContext.HTTP_CONNECTION, conn);
context.setAttribute(ExecutionContext.HTTP_TARGET_HOST, host);

    try {

      String[] targets = { "/", "/help.jsp" };

      for (int i = 0; i < targets.length; i++) {
if (!conn.isOpen()) {
Socket socket = new Socket(host.getHostName(), host.getPort());
conn.bind(socket, params);
}
BasicHttpRequest request = new BasicHttpRequest("GET", targets[i]);
System.out.println(">> Request URI: " + request.getRequestLine().getUri());

        context.setAttribute(ExecutionContext.HTTP_REQUEST, request);
request.setParams(params);
httpexecutor.preProcess(request, httpproc, context);
HttpResponse response = httpexecutor.execute(request, conn, context);
response.setParams(params);
httpexecutor.postProcess(response, httpproc, context);

        // 返回码
System.out.println("<< Response: " + response.getStatusLine());
// 返回的文件头信息
Header[] hs = response.getAllHeaders();
for (Header h : hs) {
System.out.println(h.getName() + ":" + h.getValue());
}
// 输出主体信息
System.out.println(EntityUtils.toString(response.getEntity()));
System.out.println("==============");
if (!connStrategy.keepAlive(response, context)) {
conn.close();
} else {
System.out.println("Connection kept alive...");
}
}
} finally {
conn.close();
}
}
}

 5、httpclient中文乱码解决

httpclient默认使用ISO-8859-1读取http响应的内容，如果内容中包含汉字的话就得动用丑陋的new String(str.getBytes("ISO-8859-1"),"GBK");语句了。 

解决办法就是使用以下配置。

private static final String CONTENT_CHARSET = "GBK";// httpclient读取内容时使用的字符集

HttpClient client = new HttpClient();
client.getParams().setParameter(HttpMethodParams.HTTP_CONTENT_CHARSET, CONTENT_CHARSET);

 6、HttpClient 4处理文件上传的例子(MultipartEntity)

import java.io.File;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.mime.MultipartEntity;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.entity.mime.content.StringBody;
import org.apache.http.impl.client.DefaultHttpClient;

/**
* HttpClient 4处理文件上传的例子(MultipartEntity).<br>
* 需要 James Mime4j 0.5的版本，0.6的不行。
* 
* @author JAVA世纪网(java2000.net, laozizhu.com)
*/
public class HttpClientMultipartFormPost {
public static void main(String[] args) throws Exception {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://localhost");
// 一个本地的文件
FileBody bin = new FileBody(new File("d:/BIMG1181.JPG"));
// 一个字符串
StringBody comment = new StringBody("A binary file of some kind");
// 多部分的实体
MultipartEntity reqEntity = new MultipartEntity();
// 增加
reqEntity.addPart("bin", bin);
reqEntity.addPart("comment", comment);
// 设置
httppost.setEntity(reqEntity);
System.out.println("执行: " + httppost.getRequestLine());
HttpResponse response = httpclient.execute(httppost);
HttpEntity resEntity = response.getEntity();
System.out.println("----------------------------------------");
System.out.println(response.getStatusLine());
if (resEntity != null) {
System.out.println("返回长度: " + resEntity.getContentLength());
}
if (resEntity != null) {
resEntity.consumeContent();
}
}
}