Eclipse, AppEngine: java.lang.RuntimeException: Cannot get the System Java Compiler. Please use a JDK, not a JRE

Question

I\'m getting this error when trying to deploy to Google AppEngine. I DO have JDK selected!

------------ Deploying frontend ------------

Preparing to deploy:
            


        

Answer 1

I see that the OP is using Google Plugin for Eclipse (GPE), which is deprecated, but this was once also a problem in Cloud Tools for Eclipse (CT4E), so I'll leave a relevant answer for CT4E here for reference.

It was indeed a bug of Cloud Tools for Eclipse that it did not use the JDK configured for a project but instead used the JDK used to launch Eclipse for staging. The bug has been fixed: https://github.com/GoogleCloudPlatform/google-cloud-eclipse/issues/2195.

So, others answers in this question to edit eclipse.ini to change the JDK to launch Eclipse are a temporary workaround that is no longer needed. Just update to the latest CT4E version and set a JDK for a project. You can specify whatever JDK/JRE necessary in eclipse.ini for launching Eclipse.