import java.util.*;

public class Command
{
    public static final String MASK = "mask";
    public static final String MEM = "mem";
    public static final String OPEN_BRACE = "[";
    public static final String CLOSE_BRACE = "]";
    public static final String EQUALS = "=";

    public Command (String mask, Vector<String> cmds)
    {
        _mask = mask;
        _commands = cmds;
    }

    public void execute (HashMap<Long, Long> memory)
    {

    }

    @Override
    public String toString ()
    {
        String str = _mask;

        for (int i = 0; i < _commands.size(); i++)
        {
            str += "\n" + _commands.elementAt(i);
        }

        return str;
    }

    private String _mask;
    private Vector<String> _commands;
}
@@ -446,16 +446,90 @@
 )%0A    %7B%0A
+        String theMask = _mask.substring(_mask.indexOf(EQUALS) +1).trim();
 %0A    %7D%0A%0A

Update Command.java