code: @Override
  	public ZooClass getClass(Class<?> cls) {
  		DBTracer.logCall(this, cls);
  		checkValidityRead();
  		return sm.locateSchema(cls, null);
  	}
docs: Locate the class definition for the given class.
  @param cls The Java class whose schema should be returned
  @return The class definition or {@code null} if the class is not defined in the database
  @see ZooSchema#getClass(Class)