/*
 * RandomFileAccessor.java
 *
 * This program reads back a value from a user-specified position in the file
 * created by BinaryFileMaker.java, and displays it as all possible data types.
 * See that program for a description of the file
 *
 * Copyright (c) 2000, 2004 - Russell C. Bjork
 *
 */

import java.io.*;
import javax.swing.*;

public class RandomFileAccessor
{
    public static void main(String [] args) throws IOException
    {
        // Open the file
        
		File filename;
		JFileChooser chooser = new JFileChooser(System.getProperty("user.dir"));
		if (chooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION)
		{
			filename = chooser.getSelectedFile();
		}
		else
			return;
			
        RandomAccessFile input = new RandomAccessFile(filename, "r");
        
		do
		{
			// Get the position in the file
		
			String positionString = JOptionPane.showInputDialog(
				"Position (cancel to quit): ");
			if (positionString == null)
				break;	// Exit loop when null is entered
			long position = Long.parseLong(positionString);
			
	        // Read the values from the file
        
			input.seek(position);
			boolean booleanValue = input.readBoolean();
			input.seek(position);
			char charValue = input.readChar();
			input.seek(position);
			byte byteValue = input.readByte();
			input.seek(position);
			short shortValue = input.readShort();
			input.seek(position);
			int intValue = input.readInt();
			input.seek(position);
			long longValue = input.readLong();
			input.seek(position);
			float floatValue = input.readFloat();
			input.seek(position);
			double doubleValue = input.readDouble();
			// Don't try the string
					
			// Write out what we read
			
			System.out.println();
			System.out.println("Values read as various types at position " +
				position);
			System.out.println("boolean: " + booleanValue);
			System.out.println("char:    " + charValue);
			System.out.println("byte:    " + byteValue);
			System.out.println("short:   " + shortValue);
			System.out.println("int:     " + intValue);
			System.out.println("long:    " + longValue);
			System.out.println("float:   " + floatValue);
			System.out.println("double:  " + doubleValue);
			System.out.println();
		}
		while(true);	// Loop is mid-exit
		
        // Close the file and we're done
        
        input.close();
        System.exit(0);
        
     }
}