DescriptorFactory.java 文件源码

private DescriptorProto createMessageDescriptorProto(String messageName, 
    UnknownFieldSet unknownFields) {
  DescriptorProto.Builder messageBuilder = DescriptorProto.newBuilder();
  return messageBuilder
      .setName(messageName)
      .setUnknownFields(unknownFields)
      .addAllEnumType(Collections.<EnumDescriptorProto>emptyList())
      .addAllExtension(Collections.<FieldDescriptorProto>emptyList())
      .addAllField(Collections.<FieldDescriptorProto>emptyList())
      .addAllNestedType(Collections.<DescriptorProto>emptyList())
      .build();
}