programatic diff tool

[Joe Von]

I'm writing a tool which (among other things) needs to determine if two text files are different and, if different, which line has changed.
Does anyone know of a tool or an API which I can code to which has this sort of functionality?
Thanks,
Joe

[BJ Grau]

Just use the io package. Do something like this to read your files:
File f = new File("c:\\file.txt");
FileReader fr = new FileReader(f);
LineNumberReader lnr = new LineNumberReader(fr);
String lineText = "";
int lineNumber = 0;
while(text != null)
{
line = lnr.getLineNumber();
text = lnr.readLine();
}
This bit of code should read a file and grab each line, putting it into a String. Just do this to the two files you are interested in, and do a .equals between each line you read in.
Hope this helps.

[BJ Grau]

Oops! An error in my code:
line = lnr.getLineNumber();
text = lnr.readLine();
should read
lineNumber = lnr.getLineNumber();
lineText = lnr.readLine();

[Joe Von]

Cool.
Thanks BJ.