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

/**
 * Read from a file given as a URL. Throw a nasty exception in any problem
 * happens when manipulating the URL.
 */

public class InputURL
{
    // the url of the file to read from
    private URL url;
    // the stream used to read from the file
    private BufferedReader in;

    public InputURL(String URLName)
    {
        // URL of the file
        try{
            url = new URL(URLName);
        }
        catch(MalformedURLException me){
            me.printStackTrace();
            throw new Error("Can't create URL");
        }

        // Create an input stream from the file
        try{
            in = new BufferedReader( new InputStreamReader(url.openStream()));
        }
        catch(IOException ioe){
            ioe.printStackTrace();
            throw new Error("Can't open a stream from the file");
        }
    }

    /**
     * Close the input stream when done with this InputURL
     */
    public void finalize()
    {
        try{
            in.close();
        }
        catch(IOException ioe){
            ioe.printStackTrace();
            throw new Error("Error while closing the file");
        }
    }

    /**
     * Read a line from the file
     */
    public String readLine()
    {
        try{
            return in.readLine();
        }
        catch(IOException ioe){
            ioe.printStackTrace();
            throw new Error("Error while reading from the file");
        }
    }
}