Unfortunately Apache NetBeans 11.0 does not currently support the addition or use of a WebLogic server. See open Apache NetBeans Bug Report 2476: Netbeans 11 EE Support Weblogic Server
I don't know for sure, but I suspect that this is a legal problem is related to licensing issues rather than any technical obstacles. The absence of licensing on Apache NetBeans 11.0 also impacts other important products such as Hibernate (NETBEANS-2719 Resolve Hibernate Support), and Wildfly (NETBEANS-2415
Bring back support for WildFly server).
There are licensing issues because Apache assumed ownership of NetBeans releases from Oracle last year.
Also, because WebLogic was supported "out of the box" in NetBeans 8.2 there is no old WebLogic plugin available for use on Apache NetBeans 11.0.
Your options are:
- Regress NetBeans to use the most recent NetBeans release which does support WebLogic: Oracle NetBeans 8.2. Note that this means you cannot develop using Java EE 8, nor use any JDK version > 8.
- Stick with Apache NetBeans 11.0, and instead of WebLogic use one of the four application servers which it formally supports "out of the box": Payara, Glassfish, Apache Tomcat and Apache TomEE.
- Install your WebLogic server outside of Apache NetBeans 11.0, and deploy your NetBeans web applications to that external server.