代理上网

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.PasswordAuthentication;
import java.net.URL;

public class ProxyConnTest {
	public static void initProxy(String host, int port, final String username,
			final String password) {
		Authenticator.setDefault(new Authenticator() {
			protected PasswordAuthentication getPasswordAuthentication() {
				return new PasswordAuthentication(username,
						new String(password).toCharArray());
			}
		});
		System.setProperty("http.proxyType", "4");
		System.setProperty("http.proxyPort", Integer.toString(port));
		System.setProperty("http.proxyHost", host);
		System.setProperty("http.proxySet", "true");
	}

	public static void main(String[] args) throws IOException {
		String url = "http://www.luoxiaoping.com";
		String proxy = "192.168.0.3";
		int port = 8080;
		String username = "";
		String password = "";
		String curLine = "";
		String content = "";
		URL server = new URL(url);
		initProxy(proxy, port, username, password);
		HttpURLConnection connection = (HttpURLConnection) server
				.openConnection();
		connection.connect();
		System.out.print(connection.getResponseMessage());
		InputStream is = connection.getInputStream();
		BufferedReader reader = new BufferedReader(new InputStreamReader(is,
				"utf-8"));
		while ((curLine = reader.readLine()) != null) {
			content += curLine;
		}
		System.out.println("content= " + content);
		is.close();
	}
}