Constructors

[Harris1995]

Constructors are used to assign the default values to the variables so can't we use the mutator function for doing the same ?

[razzle]

can't we use the mutator

Not if the object is immutable (cannot be changed after construction).

Avoid mutators (setters), that's a fine design principle.

[Harris1995]

Not if the object is immutable (cannot be changed after construction).

Avoid mutators (setters), that's a fine design principle.

Can You explain in more detail . Thanks

[razzle]

Can You explain in more detail .

Not this time because your other questions indicate it will be very hard to give a meaningful explanation at your current level of knowledge.

So I limit my reply to the pure technical observation that if an object is immutable using a mutator is no option because there won't be any.

And even if a mutator is available and is used to set a default value the setting must take place within the constructor because otherwise it won't be a default value.