Tomcat with Java 17+

Deploying i-net Clear Reports reporting.war in Tomcat may result in errors in the log file:

[Config,ERROR ,9/28 9:37:16,#00002] java.lang.reflect.InaccessibleObjectException: Unable to make field static java.util.Hashtable accessible: module java.base does not "opens" to unnamed module @447582b6
[Config,ERROR ,9/28 9:37:16,#00002] Could not register the URL protocol: data
[Config,ERROR ,9/28 9:37:16,#00002] unknown protocol: data

The solution requires to add java.base/ to the allowed modules. You can do this in the following ways:


You have to update the catalina.bat with the following JDK_JAVA_OPTIONS:

set "JDK_JAVA_OPTIONS=%JDK_JAVA_OPTIONS% --add-opens=java.base/"

Now restart the server.

Linux / macOS

You have to update the with the following JDK_JAVA_OPTIONS:

JDK_JAVA_OPTIONS="$JDK_JAVA_OPTIONS --add-opens=java.base/"

Now restart the server.

Docker Container

In a Docker container, where the Tomcat is installed, it may suffice to set the environment variable, e.g. using:

export JDK_JAVA_OPTIONS="--add-opens=java.base/"