code: public static void assertTrueOfInvalidConstructor(boolean expression, ModelClass<?> entity) {
  		if (!expression) {
  			String msg = String.format(
  					"Class '%s' has no constructor without parameters (to be a mutable class) or with all parameters (to be an immutable class).",
  					entity.getElement().getQualifiedName());
  			throw (new InvalidDefinition(msg));
  		}
  
  	}
docs: When a pojo has a valid constructor
  
  @param expression
  @param entity