Got “unsupported class file version 52.0” after including a module to a project

Question

After creating an empty project within Android Studio and including a pure java module, which compiles and works perfectly on its own, I get the following error on every sin

Answer 1

I've faced similar errors while building the project.

Error:PARSE ERROR
Error:unsupported class file version 52.0

I faced these errors after I've switched from Java 1.8 to Java 1.7. My project consists of several libraries, 1 app module, 3 Android library modules and 2 Java library modules. I didn't change anything in Android libraries, but added the following lines in dependencies of build.gradle files of Java libraries.

sourceCompatibility = 1.7
targetCompatibility = 1.7

It solved the problem for me. Parsing error was mainly because the Java 1.8 classes couldn't be parsed into Java 1.7 classes.