Necessity of getter methods [duplicate]

Question

Possible Duplicate:
Why use getters and setters?

This is a newbie question. Is it very much necessary to use getmethods to access property values? Once the value has been assigned, one can get the values directory. For example, in the below code, displayName() can display firstName value without the help of any getter method. Or it is a standard coding standards that one must have getter and setter method or any other methods which gives that value?

class Test{

    private String firstName;

    public void setName(String fname){
        firstName = fname;
    }

    public void displayName() {
        System.out.println("Your name is " + firstName);
    }
}          

Answer 1

Tell, Don't Ask is an important principle in object-oriented design. Generally you should tell objects to do things rather than ask them questions. getters/setters every where discourage this practise because you are encouraged to reach inside an object and get to the fields (or even worse reach in and poke things about in the case of setters). This breaks encapsulation and makes your code harder to reason about.

In your particular case, I'd create an object called Name that has a constructor taking the name and single method to display it.

Answer 2

In Your case (to display the display name) it is not neccessary to provide Getter.

But if your want use the field in another class We need to provide the Getter method.

Answer 3

Getter and setters are a part of the standard interface for Java Beans and many frameworks like Hibernate expect them in place. That being said it is of course up to you to decide if and when you need them and for what purpose. They provide access to your private member variables and they can even give you the chance to do more than just plain get and set.

The point of OO software is reuse. This means that other programmers, or you years from now, can use the code for other systems.

When you have private member variables, and use get/set functions, you can change the internal implementation of the function without breaking all the other code that uses it.