What is difference between the instanck block and constructor?

Answer 1

Both will be execute when you create an object. At first the instance block and then the constructor.

A constructor can get values. For example:
public myClass(int num){
this.num = num;
}

In an instance block you could do this:
{
num = 7;
}

But without an constructor it is not possible to create an object with a specific value. You would need to write a setter for int num and to call this method.

//with constructor
MyClass my = new MyClass(4);

//without constructor
MyClass my = new MyClass();
my.setNum(4);

Here is a code about static and instance block:

https://code.sololearn.com/cRKxAwr2rE6t/?ref=app

Answer 2

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