A utility that figures out which classes need recompiling and submits them to the
compiler. A make utility is unnecessary in Java. You just pass everything to javac.exe and it figures out for itself what needs recompiling.
What if everything won’t fit on the command line? Use the sun.tools.javac.Main interface to javac.exe. Then you can pass it a command line as long as you
want. There is no need to resort to make. This technique is
much faster than using make because the javac.exe compiler gets loaded into RAM (Random Access Memory)
only once, not once per class.