Now that you have added fields to a class and can store data, you need to consider the validity of that data. As you saw in Listing 5.3, it is possible to instantiate an object using the
new operator. The result, however, is the ability to create an employee with invalid data. Immediately following the assignment of
employee, you have an
Employee object whose name and salary are not initialized. In this particular listing, you assigned the uninitialized fields immediately following the instantiation of an employee, but if you failed to do the initialization, you would not receive a warning from the compiler. As a result, you could end up with an
Employee object with an invalid name.
Declaring a Constructor
To correct this problem, ...