HttpClient使用代理IP

在爬取网页的时候，有的网站会有反爬虫措施，导致服务器请求拒接，可以使用代理IP来访问，解决请求拒绝的问题

代理IP分 透明代理、匿名代理、混淆代理、高匿代理

　　1、透明代理(Transparent Proxy)：透明代理虽然可以“隐藏”IP地址，但是还是可以从HTTP_X_FORWARDED_FOR来查到IP
　　　　REMOTE_ADDR = Proxy IP
　　　　HTTP_VIA = Proxy IP
　　　　HTTP_X_FORWARDED_FOR = Your IP
　　2、匿名代理(Anonymous Proxy)：匿名代理比透明代理进步了一点：别人只能知道你用了代理，无法知道你是谁
　　　　REMOTE_ADDR = proxy IP
　　　　HTTP_VIA = proxy IP
　　　　HTTP_X_FORWARDED_FOR = proxy IP
　　3、混淆代理(Distorting Proxies)：如果使用了混淆代理，别人还是能知道你在用代理，但是会得到一个假的IP地址，伪装的更逼真
　　　　REMOTE_ADDR = Proxy IP
　　　　HTTP_VIA = Proxy IP
　　　　HTTP_X_FORWARDED_FOR = Random IP address
　　4、高匿代理(Elite proxy或High Anonymity Proxy)：高匿代理让别人根本无法发现你是在用代理
　　　　REMOTE_ADDR = Proxy IP
　　　　HTTP_VIA = not determined
　　　　HTTP_X_FORWARDED_FOR = not determined

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.junit.Test;
/**
 * @author test
 * @Title: JunitHttpClient
 * @ProjectName JunitHttpClient
 * @Description: TODO
 * @date 2018/12/1216:07
 */
public class JunitHttpClient {

    @Test
    public void test()throws Exception{
        // 创建httpget实例
        HttpGet httpGet=new HttpGet("https://www.****.com");
        CloseableHttpClient client = setProxy(httpGet, "192.168.1.1", 8888);
        //设置请求头消息
        httpGet.setHeader("User-Agent","Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36");
        // 执行http get请求  也可以使用psot
        CloseableHttpResponse response=client.execute(httpGet);
        // 获取返回实体
        if (response != null){
            HttpEntity entity = response.getEntity();
            if (entity != null){
                System.out.println("网页内容为:"+ EntityUtils.toString(entity,"utf-8"));
            }
        }
        //关闭response
        response.close();
        //关闭httpClient
        client.close();

    }
    /**
     * 设置代理
     * @param httpGet
     * @param proxyIp
     * @param proxyPort
     * @return
     */
    public CloseableHttpClient setProxy(HttpGet httpGet,String proxyIp,int proxyPort){
        // 创建httpClient实例
        CloseableHttpClient httpClient= HttpClients.createDefault();
        //设置代理IP、端口
        HttpHost proxy=new HttpHost(proxyIp,proxyPort,"http");
        //也可以设置超时时间   RequestConfig requestConfig = RequestConfig.custom().setProxy(proxy).setConnectTimeout(3000).setSocketTimeout(3000).setConnectionRequestTimeout(3000).build();
        RequestConfig requestConfig=RequestConfig.custom().setProxy(proxy).build();
        httpGet.setConfig(requestConfig);
        return httpClient;
    }
}