code: public static int execute(String programName,
                                PrintWriter errWriter,
                                PrintWriter warnWriter,
                                PrintWriter noticeWriter,
                                String defaultDocletClassName,
                                ClassLoader docletParentClassLoader,
                                String... args) {
          Start jdoc = new Start(programName,
                                 errWriter, warnWriter, noticeWriter,
                                 defaultDocletClassName,
                                 docletParentClassLoader);
          return jdoc.begin(args);
      }
docs: Programmatic interface.
  @param programName  Name of the program (for error messages).
  @param errWriter    PrintWriter to receive error messages.
  @param warnWriter    PrintWriter to receive error messages.
  @param noticeWriter    PrintWriter to receive error messages.
  @param defaultDocletClassName  Fully qualified class name.
  @param docletParentClassLoader The parent class loader used when
  creating the doclet classloader. If null, the class loader used
  to instantiate doclets will be created without specifying a parent
  class loader.
  @param args   The command line parameters.
  @return The return code.
  @since 1.7