java实现使用代理服务器创建URL连接

package cn.arthurs.web;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.Authenticator;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.PasswordAuthentication;
import java.net.URL;
import java.util.Properties;
import org.apache.log4j.Logger;


public class WebUnit {
	private static final Logger log = Logger.getLogger( WebUnit.class );
	
	/**
	 * 返回一个网站的源代码,需要传入一个网站的网址
	 * @param webUrl
	 * @return
	 */
	public static String getWebContent(String webUrl){
		URL url;
		HttpURLConnection conn;
		InputStream stream;
		StringBuffer  text  =  new  StringBuffer();
		String temp="";
		try {
			url = new URL(webUrl);
			
			//如果需要代理服务器
			if(false){
				  Properties prop = System.getProperties();        
				  // 设置http访问要使用的代理服务器的地址           
				  prop.setProperty("http.proxyHost", "bmcdc.bmsa.com");        
				  // 设置http访问要使用的代理服务器的端口           
				  prop.setProperty("http.proxyPort", "1865");        
				  // 设置不需要通过代理服务器访问的主机，可以使用*通配符，多个地址用|分隔           
				  prop.setProperty("http.nonProxyHosts", "localhost|10.4.*.*");        
				  // 设置安全访问使用的代理服务器地址与端口        // 它没有https.nonProxyHosts属性，它按照http.nonProxyHosts 中设置的规则访问           
//				  prop.setProperty("https.proxyHost", "bmccisa-dc02.bmccisa.com");           
//				  prop.setProperty("https.proxyPort", "443");        
				  // 使用ftp代理服务器的主机、端口以及不需要使用ftp代理服务器的主机           
//				  prop.setProperty("ftp.proxyHost", "192.168.0.254");           
//				  prop.setProperty("ftp.proxyPort", "2121");           
//				  prop.setProperty("ftp.nonProxyHosts", "localhost|192.168.0.*");        // socks代理服务器的地址与端口           
//				  prop.setProperty("socksProxyHost", "192.168.0.254");           
//				  prop.setProperty("socksProxyPort", "8000");        
				  // 设置登陆到代理服务器的用户名和密码           
				  Authenticator.setDefault(new MyAuthenticator("[email protected]", "f3mj"));
			}
			conn = (HttpURLConnection) url.openConnection();
			conn.connect();
			stream = conn.getInputStream();
			BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
			while((temp = reader.readLine()) != null){
				text.append(temp+"\n");
			}
		} catch (MalformedURLException e) {
			log.error("输入"+webUrl+"有误!!!");
		} catch (IOException e) {
			log.error(e);
		}
		return text.toString();
	}
	 
	
	public static void main(String[] args){
//		 System.out.println(WebUnit.getWebContent("http://www.baidu.com"));
	 }
	
	static class MyAuthenticator extends Authenticator {        
		private String user = "";        
		private String password = "";        
		public MyAuthenticator(String user, String password) {            
			this.user = user;            
			this.password = password;           
		}        
		protected PasswordAuthentication getPasswordAuthentication() {           
			return new PasswordAuthentication(user, password.toCharArray());           
		}       
	}
}