4. Write a class called mySphere that contains instance data that represents the sphere's diameter. Define the Sphere constructor to accept and initialize the diameter, and include getter and setter methods for the diameter. Include methods that calculate and return the volume and surface area of the sphere. Include a toString method that returns a one-line description of the sphere. Write another program (a driver class or main class), which instantiates and updates several of the mySphere objects.( in java)