Lessons 6 & 7

Bekjava · August 5th, 2015, 02:46 AM

Hi
I am fairly new to Java. Trying to learn on my own. Please help me with the following two questions:

(1) Why do we need to place the executable class in a separate package in both lessons 6 & 7?
(2) The subclasses(Employee, Contractor etc.) that implement the interface payable have a method declared as a Boolean that returns in "true" or "false". I tried to change the return values and there was no difference in the output. My question is when do we return true or false and why?

Thanks,
Bek

Cristina · August 7th, 2015, 02:38 PM

Hi Bek,

Indeed, the boolean return value of the increasePay method is not used in the program. To see a difference in the output determined by the result of increasePay, I modified the code in the main method as follows:

Code:

for (Person p: workers){
	        System.out.println(((Payable)p).increasePay(30)?"Done":"Failed");
	 		}

Regarding your first question, I think placing the class that contains the main method in a separate package is a matter of choice. You can organize the files in your project according to your own design. For example, if you want to change the location of the compiled classes in Eclipse, you can do so by selecting Project->Properties->Java Build Path->Source and modifying the name of the Default Output Folder.

Happy learning!

Cristina