Should I always use a constructor?

If you don’t implement a constructor, the compiler will implictly create a default constructor if the class needs a constructor. So it depends on what you’re really asking. If you’re asking if you can write a class without explicitly creating a user defined constructor, yes you can do that.

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Is a constructor mandatory for a class?

Users do not need to write constructors for every class . A constructor can be declared using any of the access modifiers. It is mandatory to have a constructor with the right access modifier. However, the compiler supplies a default if an access modifier is not defined in the class and a constructor is not declared.

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