GamepackDownloader.java

package org.utils;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.jar.JarFile;

public class WebUtility {
	public static String getGamepackURL() throws IOException
	{
		String line;
		ArrayList<String> list = new ArrayList<String>();
		/*
		 * 
		 * Build the URL and open the connection
		 * 
		 */
		String location = "http://www.oldschool.runescape.com/jav_config.ws";
		URL url = new URL(location);
		URLConnection connection = url.openConnection();
		
		/*
		 * 
		 * Set up the reader and read out
		 * 
		 */
		
		InputStream in = connection.getInputStream();
		InputStreamReader inr = new InputStreamReader(in);
		
		BufferedReader bufr = new BufferedReader(inr);

		while((line = bufr.readLine()) != null)
		{
			list.add(line);
		}
		bufr.close();
		
		/*
		 * 
		 * Gets the codebase and initial jar location
		 * 
		 */
		
		String codebase = getCodebase(list);
		String jar = getInitialJar(list);
		return codebase + jar;
	}
	
	private static String getCodebase(ArrayList<String> list)
	{
		String raw = list.get(2);
		String[] filtered = raw.split("codebase=");
		for(String s : filtered)
		{
			if(s.startsWith("http"))
			{
				return s;
			}
		}
		return null;
	}
	
	private static String getInitialJar(ArrayList<String> list)
	{
		String raw = list.get(5);
		String[] filtered = raw.split("initial_jar=");
		for(String s : filtered)
		{
			if(s.startsWith("gamepack"))
			{
				return s;
			}
		}
		
		return null;
	}
	
	public static JarFile downloadGamepack(String location) throws IOException
	{
		try
		{
			OutputStream out;
			InputStream in;
			int read;
			
			URL url = new URL(location);
			URLConnection connection = url.openConnection();
			in = connection.getInputStream();
			
			out = new FileOutputStream("/home/pi/Downloads/downloadedJar.jar");
			
			while((read = in.read()) != -1)
			{
				out.write(read);
			}
			
			out.flush();
			out.close();
			
			JarFile file = new JarFile("/home/pi/Downloads/downloadedJar.jar");
	
			return file;
		} catch(Exception e)
		{
			e.printStackTrace();
		}
		return null;
	}

}