When I started learning Java (infact I still am) I was stuck in assignment to open the net connection, which was outside our institute firewall. The document at Sun’s website explains in depth the traditional, as well as the latest way (Use of Proxy class/Proxy Selector)to use Proxies to connect to a network. To refresh what I used, here is the code using the traditional method.

package com.aminur.java.core;
import java.util.*;
import java.net.*;
import java.io.*;

public class ReadUrl {
	private static final String proxyHost = "http://yourproxyhost"; 
	private static final String proxyPort = "8080"; 
	public static void main(String args[]) {

		System.out.println("Connecting using proxy ...");

		URLConnection smrConnection = null;
		BufferedReader in = null;
		String inputLine;
		
		System.setProperty("http.proxyHost", proxyHost);
		System.setProperty("http.proxyPort", proxyPort);
		Authenticator.setDefault(new MyAuthenticator());

		try {
			URL subjectURL = new URL("http://www.aminurrashid.com");
			smrConnection = subjectURL.openConnection();
			in = new BufferedReader(new InputStreamReader(smrConnection
					.getInputStream()));
		} catch (Exception E) {
			System.out.println(E);
		}
		try {
			while ((inputLine = in.readLine()) != null) {
				System.out.println(inputLine);
			}
		} catch (Exception E) {
		}
	}
}


class MyAuthenticator extends Authenticator {

	protected PasswordAuthentication getPasswordAuthentication() {
		return new PasswordAuthentication("userName", "Password".toCharArray());
	}
}
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