Should a SETTER always have "this" keyword? Or can it even work without it?

Question

class Animal
{
private int age;
void setAge(int x)
{
age = x; //instead of THIS.AGE = X;
/* Wrote the above line in uppercase just to highlight and that's it. No syntax issues */
}

int getAge ( )
{
return age;
}
}

Answer 1

Yes, it can work even without this keyword.

Answer 2

You need to use "this" for example, when the object variable and the constructor parameter have the same name:
class A {
int variable;
public A (int variable) {
this.variable = variable;
}
}

Answer 3

To my knowledge, you don't have to use the "this" keyword to set a value, though it's always best to.

Answer 4

Thanks a lot everyone. :)