About maven jdk version configuration problem

hi:

Guocheng Zhang, Guo Jiwei

I found some problems with the current maven jdk version configuration. For the 1.8 syntax, it can be compiled, but there will be problems during runtime.
for example:
The core module uses the syntax of 1.8. If you refer to the method that is only available in 1.8, it can be compiled. However, because the server is configured with the syntax of 1.7, when the server is running on jdk1.7, it will caused method not found errors because it depends on the core module.
In response to this problem, please ask Guocheng Zhang to determine the specific jdk running version of the server and client module, so as to make corresponding adjustments to the maven configuration. When the syntax is wrong, you can find and solve the problem in time during compilation