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Compare text files

Monish Chandrasekar

Joined: Feb 07, 2013
Posts: 2

Im trying to compare two text files in java, I wanted the source file and target file to be displayed side by side and the line which is different needs to be highlighted

I tried with this code, But it only shows the difference, what will I need to change to display two files side by side Like in

Tony Docherty

Joined: Aug 07, 2007
Posts: 2839
If you want to do it like the link you'll need a GUI.
If you want to keep it as CLI, print out the files side by side with some marker to show lines that don't match then add a print statement to the if statement that compares the lines for equality. You will need to change the chars you insert between the two concatenated lines so you can see which lines are not the same.
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46407
And welcome to the Ranch
Ulf Dittmer

Joined: Mar 22, 2005
Posts: 42965
If you want to minimize your work, use Runtime.exec to run "diff" on the two files and do something with its output (You'd need Unix/Linux underneath, or UnxUtils installed on Windows, though.)

Or check out and
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46407
Don’t use StringTokenizer (← click here and it tells you why).
Don’t use a 10000 element array. The alternatives to tokenizer can produce an array of the right size.
I agree. Here's the link:
subject: Compare text files
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