What is the test for determining the rights and duties of the parties in an action for declaratory relief?

There is no merit whatever in plaintiffs' apparent suggestion that the court erred in declaring the rights and duties of the parties on the basis of the pleadings, the stipulations and the pre-trial conference order. 'The propriety of adjudicating the respective contentions of the parties upon the pleadings in an action for declaratory relief by means of a motion for judgment on the pleadings is recognized and established in this state.' (Wilson v. Board of Retirement, 156 Cal.App.2d 195, 201, 319 P.2d 426, 429.)