Tuesday, May 27, 2014

Caveats on Using WebLogic Server with JDK7

Now JDK 7 has been out for a while (JDK 8 is out too as of writing). There are some caveats using WebLogic Server with JDK 7 you might want to know, not matter it's on 10.3.6 or 12c.

1. Out of memory error on starting Admin Server. This error is caused by the fact that the new JVM requires more PermGen space. Depending on your RAM, you can set it >350m. In my case, I would set the perm size to 512M.

-XX:MaxPermSize=512m

2. In some cases, the new compiler generates larger byte code. It is possible that a large method may exceed the 64KB limit per method. In this situation, you may need to refactor the method. This seems to only affect WebLogic 10.3.6

3. Classes may have been removed that are from the internal package sun.*, or that have been marked as deprecated in a previous version of the JVM. If an application uses these removed methods, a ClassNotFound exception will occur.

4. JDBC 4.1 is introduced in JDK7. JDBC 4.1 methods are not currently supported in WebLogic Server with JDK 7. Calls to these methods will result in an SQLException indicating that the method is not supported.

If you are using WebLogic 10.3.6, after installing WebLogic Server, copy the following files from WL_HOME/modules to JAVA_HOME/jre/lib/endorsed, where WL_HOME is the WebLogic Server installation home directory:
  • javax.annotation_1.0.0.0_1-0.jar
  • javax.xml.bind_2.1.1.jar
  • javax.xml.ws_2.1.1.jar

Reference:

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