Performs a compile using the Javac externally.
attributes.log("Using external apt compiler", Project.MSG_VERBOSE);
// Setup the apt executable
Apt apt = getApt();
Commandline cmd = new Commandline();
cmd.setExecutable(apt.getAptExecutable());
setupModernJavacCommandlineSwitches(cmd);
AptCompilerAdapter.setAptCommandlineSwitches(apt, cmd);
int firstFileName = cmd.size();
//add the files
logAndAddFilesToCompile(cmd);
//run
return 0 == executeExternalCompile(cmd.getCommandline(),
firstFileName,
true);