Choose Java 7 JRE to run App Engine Dev Server with Cloud Tools for Eclipse

[Alex R via StackOverflow]

I try to run my maven App Engine project using Google Cloud Tools for Eclipse. Using "Run As > App Engine" as suggested in the docs results in the project being run in a Java 8 runtime (same as Eclipse uses). App Engine only supports Java 7. The only execution environment in the Eclipse installation is a Java 7 JRE.

How can I make the Dev Server use the Java 7 JRE?

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http://stackoverflow.com/questions/44030994/choose-java-7-jre-to-run-app-engine-dev-server-with-cloud-tools-for-eclipse