1. Don't put your code under cop5555_token/
Put your code in cop5555 package.
This means that your java files should be under cop5555directory.
cop5555 directory should be at the same level as cop5555_token.

.../PLP/HomeWork/.../
    cop5555/Your java files include Scanner.java, SimpleParser.java, ...
    cop5555_token/Token.java, IdentToken.java, ...
       . . .
2. jar at top level of your project directory with name cop5555.jar.
Don't use zip or Homework.jar, etc.

1. Don't change public method signature.
2. Don't call System.exit() unless directed to do.
In HW2, you may call System.exit(1) when the Scanner next() throws IOException.
Except this, never call System.exit. If error occurrs so that your program cannot continue, then you can throw RuntimeException instead of System.exit(). Test drive will handle this.

  if ( error )
   throw new RuntimeException(error_msg);

instead of

  if ( error ) {
   System.err.println(error_msg);
   System.exit(-1);
  }