Gradle doesn't run because it can't find tools.jar in JRE

Today, when I was uploading new version of EasyFlipView library on jCenter, then I found this strange error which was not rebuilding my whole library module. The error was

Execution failed for task ':app:compileDebugJavaWithJavac'.
    Could not find tools.jar. Please check that C:\Program Files\Java\jre1.8.0_121 contains a valid JDK installation.

I tried googling around and found answers on StackOverflow like this and this. I tried different solutions. Here’s the one which was very simple and worked for me in an instant.


Add this to\\Program Files\\Java\\jdk1.8.0_91

Don’t forget to use double back slashes. For example:\\Program Files\\Java\\jdk1.8.0_144\ .

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Wajahat Karim is Pakistan’s first Google Developer Expert in Android. As an experience Android developer, he deeply cares about it and keeps writing and speaking about it. He has written two worldwide 300+ pages books on Android development with more than 100 articles around the internet either on his website or his Medium publications. He is also a passionate contributor in open source and has created many Android libraries used by thousands of developers in their apps worldwide. As active public speaker, he spends lots of time giving talks in conferences and motivating people on Android development. You can find Wajahat most active on Twitter @WajahatKarim where he regularly shares all the good stuff about Android and community building.

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Wajahat Karim

🔥 Google Dev Expert (GDE) in Android .
📱 Android Dev. 💻 Open Source Contributor . 📝 Technical Writer . 🎤 Public Speaker

Senior Android Developer

Karachi, Pakistan