Install libmsv-java by entering the following commands in the terminal:
sudo apt update sudo apt install libmsv-java
Sun multi-schema XML validator
The Sun Multi-Schema XML Validator is a Java tool to validate XML documents against several kinds of XML schemata. It supports DTD, RELAX Namespace, RELAX Core, RELAX NG, TREX, and a subset of W3C XML Schema Part 1. . It features both a command line utility that can read XML documents and validate them against a schema and a library that can be incorporated in a Java program.