Lacking a Maven plugin, I would do this with a small Java unit test which runs a schema validator over your example inputs - you could use a Maven filter to choose which file to parse based on your environment. If all configurations are stored in your SCM, you should be able to validate all configurations with one unit test.

If you're looking for a library to use in your unit test, have a look at the JSON schema validator:

<dependency>
    <groupId>com.github.fge</groupId>
    <artifactId>json-schema-validator</artifactId>
    <version>2.0.1</version>
    <scope>test</scope>

Another thought - if your configuration needs runtime validation, you should use the above library to validate when it changes. If you make your configuration update process interactive, you could validate as it changes and reject configuration updates which are invalid.