Sorry for my poor English. I use the spigot 1.7.10. But it tells that can't find the class com/google/gson/JsonSyntaxException. It must be higher version to execute this plugin?

Yea I encountered the same problem. 1.7.10 is missing some methods and is terribly outdated. I may fix this in the future, but right now 1.7 isn't supported.

Sorry to comment on a closed issue. To fix this you need to include the gson library within the plugin. Gson wasn't added to the server jar until version 1.8.3. I've had this problem before myself and managed to fix it doing this.

Yea. I will take a look at it, on rather just disabling the 2 methods that use gson for 1.7, or putting gson into the plugin. Kinda annoying to have patch around this much to get it working on a 3-year-old mc version^^.