Blogs

Just a quick one today that will hopefully save you some time if you hit this yourself...

I'm updating a workspace to use JDK-21 (it was previously working fine w/ JDK-11).

When I started Tomcat, I immediately got an error:

10-Oct-2024 15:36:08.783 SEVERE [main] org.apache.catalina.startup.HostConfig.
    deployDescriptor Error deploying deployment descriptor 
    [tomcat/conf/Catalina/localhost/ROOT.xml]
  java.lang.IllegalStateException: Error starting child
    [snip]
  Caused by: org.apache.catalina.LifecycleException: Failed to start component 
      [StandardEngine[Catalina].StandardHost[localhost].StandardContext[]]
    [snip]
  Caused by: java.lang.ExceptionInInitializerError
    at com.liferay.petra.reflect.ReflectionUtil.(ReflectionUtil.java:125)
    at com.liferay.portal.kernel.util.ProxyUtil.(ProxyUtil.java:200)
    [snip]
  Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make field 
      static final java.lang.invoke.MethodHandles$Lookup 
      java.lang.invoke.MethodHandles$Lookup.IMPL_LOOKUP accessible: module 
      java.base does not "opens java.lang.invoke" to unnamed module @2f860823
    [snip]
10-Oct-2024 15:36:08.798 INFO [main] org.apache.catalina.startup.Catalina.start 
    Server startup in [241] milliseconds

The key here, and the one that I hope Google is indexing and that's how you got here, is this exception:

java.lang.reflect.InaccessibleObjectException: Unable to make field static final java.lang.invoke.MethodHandles$Lookup java.lang.invoke.MethodHandles$Lookup.IMPL_LOOKUP accessible: module java.base does not "opens java.lang.invoke" to unnamed module

When you get this message, it's a sign that your JDK Java options are too restrictive.

In my case, I had an existing setenv.sh file that I had pulled forward and was using. It contained the one line:

JDK_JAVA_OPTIONS="$JDK_JAVA_OPTIONS --add-opens=jdk.zipfs/jdk.nio.zipfs=ALL-UNNAMED"

Remember that old fix for JDK 11.0.20+ that we needed to fix zip file access? Well, that's what this line was for.

However, for JDK 17 and JDK 21, Liferay needs a few more additions... The complete list is:

• --add-opens=java.base/java.lang=ALL-UNNAMED
• --add-opens=java.base/java.lang.invoke=ALL-UNNAMED
• --add-opens=java.base/java.lang.reflect=ALL-UNNAMED
• --add-opens=java.base/java.net=ALL-UNNAMED
• --add-opens=java.base/sun.net.www.protocol.http=ALL-UNNAMED
• --add-opens=java.base/sun.net.www.protocol.https=ALL-UNNAMED
• --add-opens=java.base/sun.util.calendar=ALL-UNNAMED
• --add-opens=jdk.zipfs/jdk.nio.zipfs=ALL-UNNAMED

When you add these to your setenv.sh/setenv.bat file, those exceptions above will fall away.

Now it is quite possible that, due to your own customizations, you might encounter a similar exception...

When that happens, you're going to need to adjust your --add-opens list to include your referenced module, and have it access ALL-UNNAMED.

But how do you do it? Mostly it's going to come from the exception message itself.

We already know we're going to need an --add-opens argument, and it will equal the module which is being flagged and the "opens package" values to complete the line, and then we set it equal to ALL-UNNAMED.

So from my original exception above, the portion of the message I have to look at is module java.base does not "opens java.lang.invoke". I'm going to extract the relevant pieces to come up with --add-opens=java.base/java.lang.invoke=ALL-UNNAMED.

Hope this helps as you migrate to JDK-17 or JDK-21...