Gradle - Could not target platform: 'Java SE 8' using tool chain: 'JDK 7 (1.7)'

Finally I imported my Gradle project. These are the steps:

1. I switched from local Gradle distrib to Intellij Idea Gradle Wrapper (gradle-2.14).
2. I pointed system variable JAVA_HOME to JDK 8 (it was 7th previously) as I had figured out by experiments that Gradle Wrapper could process the project with JDK 8 only.
3. I deleted previously manually created file gradle.properties (with org.gradle.java.homevariable) in windows user .gradle directory as, I guessed, it didn't bring any additional value to Gradle.

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

For IntelliJ 2019:

Intellij IDEA -> Preferences -> Build, Execution, Deployment -> Build Tools -> Gradle -> Gradle JVM

Select correct version.

For IntelliJ 2019, JDK 13 and gRPC:

Intellij IDEA -> Preferences -> Build, Execution, Deployment -> Build Tools -> Gradle -> Gradle JVM

and Select correct version.

you might also have to adding below line in your build.gradle dependencies

compileOnly group: 'javax.annotation', name: 'javax.annotation-api', version: '1.3.2'