code: @Override
      public void execute ()
      {
          if (_checking) {
              log("Only checking if generation would change files", Project.MSG_VERBOSE);
          }
          for (FileSet fs : _filesets) {
              DirectoryScanner ds = fs.getDirectoryScanner(getProject());
              File fromDir = fs.getDir(getProject());
              String[] srcFiles = ds.getIncludedFiles();
              for (String srcFile : srcFiles) {
                  File source = new File(fromDir, srcFile);
                  try {
                      processClass(source, loadClass(source));
                  } catch (Exception e) {
                      throw new BuildException(e);
                  }
              }
          }
          if (_checking && !_modifiedPaths.isEmpty()) {
              throw new BuildException("Generation would produce changes!");
          }
  
      }
docs: Performs the actual work of the task.