Least knowledge

Before :

Let's say we have following Address class:

	class Address {
	String number
	String firstLine
	String secondLine
	String postCode
	String City
	String State
	}

view raw Address hosted with ❤ by GitHub

And we are using it in another class like Person:

	class Person {
	String firstName
	String lastName
	Address address
	}

view raw Person hosted with ❤ by GitHub

And at the end, A client code that is going to use it in this way:

	println person.getAddress().getFirstLine()
	println person.getAddress().getSecondLine()

view raw Main hosted with ❤ by GitHub

After:

Now Lets' change Person to add new methods to return first and second line of address:

	class Person {
	String firstName
	String lastName
	private Address address
	String getAddressFirstLine() {
	address.firstLine
	}
	String getAddressSecondLine() {
	address.secondLine
	}
	}

view raw Person hosted with ❤ by GitHub

So client can utilize new methods in this way:

	println person.getAddressFirstLine()
	println person.getAddressSecondLine()

view raw Main hosted with ❤ by GitHub

What are the pros & cons for each solution (before and after) ?

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