Problem
Using your knowledge of Java and object-oriented programming, give your best implementation of a type Part. A Part has three attributes, a manufacturer of type Manufacturer, a partNumber of type String, and a price of type double. Assume the type of Manufacturer already exists in your API.
1. Ensure that when we put a value of type Part, both the manufacturer and the partNumber must be specified. Whether the price must also be specified is up to you.
2. Provide a means to separately retrieve the values of the three different attributes.
3. Provide a means to change the price and the manufacturer of the part.