The museum has a collection of ART_OBJECTS. Each ART_OBJECT has a unique Id_no, an Artist (if known), a Year (when it was created, if known), a Title, and a Description. The art objects are categorized in several ways.

Acolor class has three public, integer-returning accessor methods: getred, getgreen, and getblue, and three protected, void-returning mutator methods: setred, setgreen, setblue, each of which accepts an integer parameter and assigns it to the corresponding color component. the class, alphachannelcolor-- a subclass of color-- has an integer instance variable, alpha, containing the alpha channel value, representing the degree of transparency of the color. alphachannelcolor also has a method named dissolve (void-returning, and no parameters), that causes the color to fade a bit. it does this by incrementing (by 1) all three color components (using the above accessor and mutator methods) as well as the alpha component value. write the dissolve method.