I am trying to create a simple program where i have to guess a number. Now in one of the classes i am declaring only a variable in the below format;

class player  {
    int num;  //Declaration
    num = (int) (Math.random() * 10);
}

This throws me an error that identifier required and suggests me to create another class with the name number.

But if i do

class player  {
    int num = (int) (Math.random() * 10);  //Declaration + Initialisation
}

It gets accepted without any error. I did look this up and people have asked to get the initialisation done under a method but i could not understand why. Could you please explain me the difference between the above two approach? Java

The problem is actually this line:

num = (int) (Math.random() * 10);

this can not be just done in the Class scope.

You are allowed to split declaration and initialization of a variable only if you are in a method/constructor

otherwise must be done in the same line

Note that you will see/hear about things like

class player  {
    int num;
    {
        num = (int) (Math.random() * 10);
    }
}

but it is better/ cleaner/ more clear to do that inside the constructor or a method.

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