Executing methods using an input text file

Question

Hello all,
I was just wondering if I could get a little help with giving the input commands to my program through a provided text file. I have already made a stack program and want to test it by feeding it a text file with commands in it. Here is an example of the text that it would contain:
bluePush 100
blueIsEmpty
print
bluePush 101
bluePush 102
bluePush 103
blueSize
bluePush 104
print
bluePop
print
redIsEmpty
Etc..
Problem is, I'm not really sure how to make my test file. I've never taken a text file as input before and once it's in, I'm not sure how to parse the commands.
Any help would be greatly appreciated.
Thanks,
Tyler

Answer 1

You would open the file like such:
  String fileName = "c:\path\to\file.txt";
  BufferedReader input = new BufferedReader(
                           new FileReader(fileName));You would create a loop to read the text, line by line, something like this:
  String line = null;
  while ((line = input.readLine()) != null){
    //... do processing here
  }Inside the while loop, you would parse the string into command and value pairs. Maybe look into StringTokenizer... Something like this:
    //inside while loop
    StringTokenizer parser = new StringTokanizer(line, " ");
    String command = parser.nextToken();
    String value = null;
    if (doesCommandHaveValue(command)) value = nextToken();
    //Determine course of action based on command
//*** Then have the method doesCommandHaveValue...
// Returns true if "Push" is found inside of command,
// since it looks like only push statements have values after them
private boolean doesCommandHaveValue(String command) {
  return (command.indexOf("Push") != -1);
}Then mabe do a series of ifs based on command, to call different methods, using the value read in.