Important question

Question

It the class must always have a default constructor??

Answer 1

Every class written in java by default has its parent class 'Object'. So when ever you create a new instance of your class it will directly calls it's parents class constructor .. so the answer for your question is not required. But if you want your own implementation for your constructor.. you need to create one which will override your parent class constructor.

Answer 2

You can try it yourself in code Playground

Answer 3

Benjamin Jürgens So it is false?

Answer 4

"You don't have to provide any constructors for your class, but you must be careful when doing this. The compiler automatically provides a no-argument, default constructor for any class without constructors. This default constructor will call the no-argument constructor of the superclass. In this situation, the compiler will complain if the superclass doesn't have a no-argument constructor so you must verify that it does. If your class has no explicit superclass, then it has an implicit superclass of Object, which does have a no-argument constructor."

https://docs.oracle.com/javase/tutorial/java/javaOO/constructors.html

Answer 5

Thanks all of you

Answer 6

Default constructor will be added by the compiler if you create an object in that class

Answer 7

there's no need for that ... If u don't include that compiler automatically creates default constructor

Answer 8

Benjamin Jürgens :) i want help just tell me it is true or false?

Answer 9

public class Program
{
public static void main(String[] args) {

}
}

No constructor

Answer 10

Yes, a program has its own default constructor which is called automatically at the time of object creation.
For example:-
Like we have a program of class name Counter
Then,as we create a object(object name- count)of class Counter a default constructor will be called by itself.
e.g.- Counter count=new Counter();
You can see that in above object creation statement, at the last Counter() constructor is called.

Answer 11

Not necessary when you are not calling for a custom class. And complier also creates a default constructor from its own when it doesn't get the default constructor

Answer 12

You don't have to provide any construction for your class , but you must be careful when doing this.

Answer 13

Good for 33 330 l. 0%l0....