Question

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Why use getters and setters?

Yes, It’s a very simple thing but I am not finding a good reson for this. I know it is a good practice to make a variable private and providing getter to setter to access that variable. Still Is there any reason other than this ?

Answer 1

Lookup “encapsulation” and “information hiding”.

Basically, a class manages data and provides operations on them/ give access to them, but the internal representation of that data should kept private to the class. Like this, a class can change its internal representation without breaking other code.

E.g. consider:

A)

    public Date date;

B)

    private Date date;


    public Date getDate(){...}
    public setDate(Date date){...}

Later you choose to use Calendar instead of Date.
In case A) you cannot change the data type without breaking code.

In case B) you can do:

    private Calendar calendar;


    public Date getDate(){...}
    public setDate(Date date){...}
    public Calendar getCalendar (){...}
    public setCalendar(Calendar calendar){...}

You can provide a conversion in the get/setDate methods. Client code doesn’t break.

Another reason you sometimes want to use getter and setter is the use of libraries/

frameworks which base on JavaBeans patterns.