Unnamed

package test;

import java.util.HashMap;

/**
 *
 * @author Matt Torvalds
 */
public class HexToBinary {

    private static final HashMap<Character, String> map = 
            new HashMap<Character,String>();
    
    static {
        map.put('0', "0000");
        map.put('1', "0001");
        map.put('2', "0010");
        map.put('3', "0011");
        map.put('4', "0100");
        map.put('5', "0101");
        map.put('6', "0110");
        map.put('7', "0111");
        map.put('8', "1000");
        map.put('9', "1001");
        map.put('A', "1010");
        map.put('B', "1011");
        map.put('C', "1100");
        map.put('D', "1101");
        map.put('E', "1110");
        map.put('F', "1111");
    }
    
    public static void main(String[] args) {
        final char[] hex = args[0].toCharArray();
        final StringBuilder sb = new StringBuilder();
        for (int i = 0; i < hex.length; i++) {
            sb.append(map.get(hex[i]));
        }
        System.out.println(sb.toString());
    }
}