Variable assignment: int x = x = 1 [duplicate]

Question

This is allowed by the Java compiler, what is it doing?

int x = x = 1;

I realize that x is assigned to x, but how can it have two =s?

Answer 1

x = 1 both assigns the value 1 to x and also 'returns' 1, it allows for things like this:

while ((line = reader.readLine()) != null)