日期:2014-05-16  浏览次数:20855 次

apacheco httpclient 4 学习和例子
package com.eecn.warehouse.api.action;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.entity.ContentType;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

public class HttpTest {

	    public final static void main(String[] args) throws Exception {
	 
	        // 初始化,此处构造函数就与3.1中不同
	        HttpClient httpclient = new DefaultHttpClient();
	 
	        HttpHost targetHost = new HttpHost("www.google.com.hk");
	        //HttpGet httpget = new HttpGet("http://www.apache.org/");
	        HttpGet httpget = new HttpGet("/");
	 
	        // 查看默认request头部信息
	        System.out.println("Accept-Charset:" + httpget.getFirstHeader("Accept-Charset"));
	        // 以下这条如果不加会发现无论你设置Accept-Charset为gbk还是utf-8,他都会默认返回gb2312(本例针对google.cn来说)
	        httpget.setHeader("User-Agent", "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.1.2)");
	        // 用逗号分隔显示可以同时接受多种编码
	        httpget.setHeader("Accept-Language", "zh-cn,zh;q=0.5");
	        httpget.setHeader("Accept-Charset", "GB2312,utf-8;q=0.7,*;q=0.7");
	        // 验证头部信息设置生效
	        System.out.println("Accept-Charset:" + httpget.getFirstHeader("Accept-Charset").getValue());
	 
	        // Execute HTTP request
	        System.out.println("executing request " + httpget.getURI());
	        HttpResponse response = httpclient.execute(targetHost, httpget);
	        //HttpResponse response = httpclient.execute(httpget);
	 
	        System.out.println("----------------------------------------");
	        System.out.println("Location: " + response.getLastHeader("Location"));
	        System.out.println(response.getStatusLine().getStatusCode());
	        System.out.println(response.getLastHeader("Content-Type"));
	        System.out.println(response.getLastHeader("Content-Length"));
	        
	        System.out.println("----------------------------------------");
	 
	        // 判断页面返回状态判断是否进行转向抓取新链接
	        int statusCode = response.getStatusLine().getStatusCode();
	        if ((statusCode == HttpStatus.SC_MOVED_PERMANENTLY) ||
	                (statusCode == HttpStatus.SC_MOVED_TEMPORARILY) ||
	                (statusCode == HttpStatus.SC_SEE_OTHER) ||
	                (statusCode == HttpStatus.SC_TEMPORARY_REDIRECT)) {
	            // 此处重定向处理  此处还未验证
	            String newUri = response.getLastHeader("Location").getValue();
	            httpclient = new DefaultHttpClient();
	            httpget = new HttpGet(newUri);
	            response = httpclient.execute(httpget);
	        }
	 
	        // Get hold of the response entity
	        HttpEntity entity = response.getEntity();
	        
	        // 查看所有返回头部信息
	        Header headers[] = response.getAllHeaders();
	        int ii = 0;
	        while (ii < headers.length) {
	            System.out.println(headers[ii].getName() + ": " + headers[ii].getValue());
	            ++ii;
	        }
	        
	        // If the response does not enclose an entity, there is no need
	        // to bother about connection release
	        if (entity != null) {
	            // 将源码流保存在一个byte数组当中,因为可能需要两次用到该流,
	            byte[] bytes = EntityUtils.toByteArray(entity);
	            String charSet = "";
	            
	            // 如果头部Content-Type中包含了编码信息,那么我们可以直接在此处获取
	            charSet = ContentType.getOrDefault(entity).getCharset().name();
	 
	            System.out.println("In header: &