Java – How to set sourceCompatability to javaVersion.VERSION_1_8

I installed jdk1.8.0_112 and wrote the following code in build.gradle

 compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

I get this error

Error:Jack is required to support java 8 language features. Either enable Jack or remove sourceCompatibility JavaVersion.VERSION_1_8.

Can anyone help me?

From https://developer.android.com/guide/platform/j8-jack.html, you also need the following:

  defaultConfig {
    ...
    jackOptions {
      enabled true
    }
  }

Update

Note that the Jack toolchain is now deprecated https://android-developers.googleblog.com/2017/03/future-of-java-8-language-feature.html