anchor.diff:  
   The following example validates that the value specified for the `--prime` option is a prime number:
   
  -[source,java]
  +.Java
  +[source,java,role="primary"]
   ----
   class SingleOptionValidationExample {
       private int prime;
  
positive.code: }
  ----
  
  
  
  == Parser Configuration
  
  
negative.code: 
  The picocli wiki has a https://github.com/remkop/picocli/wiki/JSR-380-BeanValidation[full example], below is a snippet:
  
  .Java
  [source,java,role="primary"]
  ----
  import picocli.CommandLine;
  import picocli.CommandLine.Model.CommandSpec;
  