Compare Two Files in Netbeans6

1. In the Projects tab, click and select with the ctrl key pressing two files.
2. Right-click one of the selected files, and select Tools > Diff from the context menu.
3. The graphical Diff view appears and lets you step through all differences.

Diffrent code blocks will be selected in different colors...

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this is very important when you want to edit a file..
clone the orginal document(Rgt on doc tab>Clone Document) and edit.. then compare...

Note :

Diff only appears in the Tools menu when two files are selected and in focus.