I'm searching within Java files for some occurrence of a phrase:
find . -name '*.java' | xargs grep -l 'string'
How do I change this command to print to the shell all of the lines which contain a match?
If your filenames contain space, ' or " you should look at GNU Parallel www.gnu.org/software/parallel/
Depending on your system this may run faster than the sequential grep as this can use multiple CPUs. Often, though, the speed of the disk will be the limiting factor.
Watch the intro video to GNU Parallel: http://www.youtube.com/watch?v=OpaiGYxkSuQ