Gradle – Could not target platform: ‘Java SE 8’ using tool chain: ‘JDK 7 (1.7)’

This is what worked for me (Intellij Idea 2018.1.2):

1) Navigate to: File -> Settings -> Build, Execution, Deployment -> Build Tools -> Gradle

2) Gradle JVM: change to version 1.8

3) Re-run the gradle task