code: public String createJavaSignature(CtMethod overridenMethod) throws NotFoundException {
          return extractModifier(overridenMethod) + " "
                  + extractReturnType(overridenMethod) + " "
                  + overridenMethod.getName() + "("
                  + extractParametersAndTypes(overridenMethod) + ")"
                  + extractThrowClause(overridenMethod);
      }
docs: Returns the signature of a method like "public abstract foo(Object o) throws Exception, Throwable".
  @param overridenMethod the method to generate the signature of.
  @return the signature of overridenMethod like "public abstract foo(Object o) throws Exception, Throwable".
  @throws NotFoundException if a type is not found (like parameter types).