React Native doesn't run on emulator?

Did everything in the official documentation.
Exposed environment variables.
Launch the Genymotion emulator.
In the console write react-native run-android throws this:

:app:mergeDebugAssets
:app:generateDebugResValues
:app:generateDebugResources
:app:mergeDebugResources
:app:bundleDebugJsAndAssets SKIPPED
:app:processDebugManifest
:app:processDebugResources
:app:generateDebugSources
:app:incrementalDebugJavaCompilationSafeguard
:app:compileDebugJavaWithJavac
:app:compileDebugJavaWithJavac - is not incremental (e.g. outputs have changed,
no previous execution, etc.).
:app:compileDebugJavaWithJavac FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:compileDebugJavaWithJavac'.
> Could not find tools.jar. Please check that C:\Program Files\Java\jre1.8.0_131
contains a valid JDK installation.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug
option to get more log output.

BUILD FAILED

Total time: 14 mins secs 47.488
Could not install the app on the device, read the error above for details.
Make sure you have an Android emulator running or a device connected and have
set up your Android development environment:
https://facebook.github.io/react-native/docs/andro...
June 26th 19 at 14:14
1 answer
June 26th 19 at 14:16
Solution
The thing is that, if set, as it is written in the official documentation - put the jre and the jdk you need to specify the JAVA_HOME environment variable.

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