科尔多瓦FCM构建失败+原因：Dex无法解析版本52字节代码

Question

我在创建构建时遇到构建问题。但是，如果我删除了FCM插件，它就可以正常工作。在当前版本中几乎没有代码更改。使用FCM之前的版本效果很好。请帮助修复。

 :transformClassesWithDexForDebugDex: Error converting bytecode to dex:
   Cause: Dex cannot parse version 52 byte code.
   This is caused by library dependencies that have been compiled using Java 
 8 
    or above.
   If you are using the 'java' gradle plugin in a library submodule add
   targetCompatibility = '1.7'
   sourceCompatibility = '1.7'
   to that submodule's build.gradle file.
    UNEXPECTED TOP-LEVEL EXCEPTION: