Server does not run on Eclipse

Question

I am developing a REST API with Java using Wildfly as a server. After installing JBoss Tools and configuring the Wildfly files, I create my server and go run it, but always get the same error:

 Error occurred during initialization of boot layer java.lang.module.FindException: Module java.se not found



  The server "WildFly 21" requires a JDK to run properly. The VM used to launch
 this server is not recognized as a valid JDK.
 C:\Users\jorge\AppData\Local\Temp\eoi7210.tmp\plugin\
org.eclipse.justj.openjdk.hotspot.jre.minimal.stripped.win32.x86_64_15.0.1.v20201027-0507\jre

Besides, if instead of running the server I debug it, it ends up on a [Starting, Synchronized] state but I also get an exception:

Cannot connect to VM
Socket closed

And again:

 Error occurred during initialization of boot layer java.lang.module.FindException: Module java.se not found

Thank you in advance to any of you that can give me a little help with this.

Answer 1

Which Java do you use when running Wildfly? The error indicates that some JRE is used while a full JDK is required.

Be aware you can install multiple versions of both JRE and JDK on a server, and the startup script will have to decide which of them to use. Typically you can set the JAVA_HOME environment variable prior to invoking Wildfly.