android - Execution failed for task ':app:compileDebugJavaWithJavac'

Question

New to Android Studio + Gradle.

I'm trying to run my app from the command line using:

gradlew installDebug

The app gets installed on my device only when I execute that command when Studio just got opened and do that initial syncing/building thing.

Whenever I modified my code, and try to run that command again, the build fails and shows this error:

Execution failed for task ':app:compileDebugJavaWithJavac'
> Could not find tools.jar

How do I solve this problem? Thanks in advance.

Answer 1

Setting the JAVA_HOME variable to C:\Program Files\Java\jdkX.XX worked for me.

It was previously set to the JRE directory for some reason.

Answer 2

Are you on Linux? What does echo $JAVA_HOME outputs?

I had a similar issue when running react-native run-android. After setting $JAVA_HOME (which hadn't existed) to a JDK folder, the problem was solved. In my case, I added the following line to the end of .bashrc file:

export JAVA_HOME="path/to/a/folder/with/JDK/jdk1.8.0_60"

and restarted the terminal.