The MXBean spec says:
"
  . . .
Otherwise, if the MXBean interface has an MXBeanMappingFactoryClass annotation, then that annotation must identify a subclass of MXBeanMappingFactory with a no-argument constructor. Then f is the result of calling this constructor. *If the class does not have a no-argument constructor, or if calling the constructor produces an exception, then the MXBean is invalid and an attempt to register it in the MBean Server will produce a NotCompliantMBeanException.*
  . . .
"

  An attempt to register such MXBean (which interface is annotated with @MXBeanMappingFactoryClass defining a class that either does not have a no-argument constructor, or calling the constructor produces an exception) causes:
 
"java.lang.IllegalArgumentException: Could not instantiate MXBeanMappingFactory javasoft.sqe.tests..."