// CSE 143, Autumn 2013
// A Downloader object stores a URL and can download a web page
// from that URL to save it to a given file on the local hard disk.

import java.io.*;
import java.net.*;

public class Downloader {
	private URL url;
	
	// Constructs a new Downloader to download from the given web site URL.
	// Precondition: urlString != null
    public Downloader(String url) throws MalformedURLException {
    	this.url = new URL(url);
    }
    
    // Saves the web page from this Downloader's URL to the given file name.
    // Throws an IOException if the web page does not exist or if anything
    // goes wrong when trying to save the file.
    public void download (String target) throws IOException {
    	InputStream in = url.openStream();
    	FileOutputStream out = new FileOutputStream(target);
    	
    	// read each byte from the URL and write it to the stream
    	int n = in.read();
    	while(n != -1) {
    		out.write(n);
    		n = in.read();
    	}
    	in.close();
    	out.close();
    }
}