code: public ASTConstructor getConstructor(ExecutableElement executableElement) {
          ImmutableList<ASTParameter> parameters = getParameters(executableElement.getParameters());
          ASTAccessModifier modifier = buildAccessModifier(executableElement);
          ImmutableSet<ASTType> throwsTypes = buildASTElementTypes(executableElement.getThrownTypes());
  
          return new ASTElementConstructor(executableElement, parameters, modifier, getAnnotations(executableElement), throwsTypes);
      }
docs: Build an ASTConstructor from the input ExecutableElement
  
  @param executableElement require input element
  @return ASTConstructor