JDiff

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
/**
 * Diff program which can handle files of any size.
 */
public class JDiff
{
    private BufferedInputStream stream1 = null;
    private BufferedInputStream stream2 = null;
    /**
     * Constructor for objects of class JDiff
     */
    public JDiff(String[] args)
    {
        try
        {
            File file1 = new File(System.getProperty("user.dir") + "/" + args[0]);
            File file2 = new File(System.getProperty("user.dir") + "/" + args[1]);
            if (file1 == null || file2 == null)
            {
                System.out.println("One or both of these files are not valid.");
                System.out.println(file1.toString());
                System.out.println(file2.toString());
                System.out.println("Please select two valid files.");
            }
            if (file1.getAbsolutePath().equals(file2.getAbsolutePath()))
            {//same path, same file
                System.out.println("These are the exact same file.");
                System.out.println(file1.toString());
                System.out.println("Please choose two different files.");
                return;
            }
            System.out.println(file1);
            System.out.println(file2);
            stream1 = new BufferedInputStream(new FileInputStream(file1));
            stream2 = new BufferedInputStream(new FileInputStream(file2));
            if (file1.length() == file2.length())
            {//files are of the same length
                int byte1 = (stream1.read() & 0xFF);
                int byte2 = (stream2.read() & 0xFF);
                long fileCntr = 0;
                while ((byte1 != -1) && (byte2 != -1))
                {
                    if (byte1 != byte2)
                    {
                        System.out.print("Address: 0x" + Long.toHexString(fileCntr).toUpperCase());
                        if (byte1 < 16)
                        {
                           System.out.print("\t0x0" + Integer.toHexString(byte1));
                        }
                        else //byte >= 16
                        {
                           System.out.print("\t0x" + Integer.toHexString(byte1));
                        }
                        if (byte2 < 16)
                        {
                           System.out.print("\t0x0" + Integer.toHexString(byte2) + "\n");
                        }
                        else //byte >= 16
                        {
                           System.out.print("\t0x" + Integer.toHexString(byte2) + "\n");
                        }
                    }
                    byte1 = stream1.read();
                    byte2 = stream2.read();
                    fileCntr ++;
                }
            }
            else
            {//files aren't the same length
                ;
            }
            System.out.println();
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        finally
        {
            if (stream1 != null)
            {
                try
                {
                    stream1.close();
                }
                catch (Exception e) {}
            }
            if (stream2 != null)
            {
                try
                {
                    stream2.close();
                }
                catch (Exception e) {}
            }
        }
    }

    public static void main(String[] args)
    {
        JDiff jdiff = new JDiff(args);
    }
}