This was the ultimate test. The integrated WebLogic Server (WLS) needed to boot up. This wasn’t a simple Tomcat servlet;
Modify the line SetJavaHome to point to your new JDK directory.
: JDeveloper 12.2.1.4 requires Java 8 (JDK 1.8) to run the IDE process and the integrated WebLogic Server.
Note: Some Oracle Fusion Middleware/ADF runtime components historically required specific Java versions — when building ADF applications intended for Oracle WebLogic or Oracle Application Server, align the JDK used for build and deployment with the target server's supported JDK. jdeveloper 12.2.1.4 java version
You likely updated to JDK 11 or higher in your system PATH . Go back to JDK 8 in the JAVA_HOME variable. Also, check the ide.conf file – it might have been overwritten to point to the new JDK.
Versions below 8u191 fail baseline infrastructure validation. JDK 1.8.0_211
Error: Unsupported major.minor version 52.0 – This means the compiled class version is correct (52 = JDK 8), but the server is using an older JDK. Ensure the integrated WebLogic (which runs on a separate JVM) also uses the same JDK 8u202. This was the ultimate test
Understanding Java Version Requirements for JDeveloper 12.2.1.4
Oracle's certification matrix for Fusion Middleware 12.2.1.4 confirms that the maximum certified JDK is Oracle JDK 1.8.0_211+, meaning any 1.8.0_xxx version is acceptable when using Oracle JDK as the JDK vendor.
set JAVA_HOME=C:\Program Files\Java\jdk1.8.0_202 : JDeveloper 12
: Requires a pre-installed certified JDK to run the generic installer.
: The built-in embedded WebLogic instance runs applications in a Java EE 7 container. Because WebLogic 12.2.1.4 is fundamentally certified to run under JDK 1.8, upgrading the IDE runtime beyond Java 8 breaks the local testing environments. Upgrading to Newer Java Versions
It is worth noting that while the certification primarily focuses on Oracle JDK, Oracle provides support for running JDeveloper on any platform that has Java SE Development Kit (JDK) 8 installed.