code: @Override
  	public ZooClass getClass(String className) {
  		DBTracer.logCall(this, className);
  		checkValidityRead();
  		return sm.locateSchema(className);
  	}
docs: Locate the class definition for the given class.
  @param className The name of the 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(String)