if (!line.trim().equals("")) {
StringTokenizer tokenizer = new StringTokenizer(line);
instructionName = tokenizer.nextToken();
opCode = instructionSet.instructionStringToCode(instructionName);
if (opCode == HVMInstructionSet.UNKNOWN_INSTRUCTION)
throw new ProgramException("in line " + lineNumber +
": unknown instruction - " + instructionName);
switch (opCode) {