Xalan-Java: exception

How to handle this:
com.sun.org.apache.xml.internal.serializer.utils.WrappedRuntimeException: Could not load the propery file 'output_xml.properties' for output method 'xml' (check CLASSPATH)
at java.xml/com.sun.org.apache.xml.internal.serializer.OutputPropertiesFactory.getDefaultMethodProperties(OutputPropertiesFactory.java:343)
at java.xml/com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.setDefaults(TransformerImpl.java:1178)
at java.xml/com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.createOutputProperties(TransformerImpl.java:1138)

https://xalan.apache.org/xalan-j/faq.html#faq-25
https://xalan.apache.org/xalan-j/faq.html#jdk14
https://xalan.apache.org/xalan-j/faq.html#environmentcheck