Is the left-to-right order of operations guaranteed in Java?

Question

Consider this function:

public static final int F(int a, int b) {
    a = a - 1 + b;
    // and some stuff
    return a;
}

Is it required

Answer 1

Yes, although the bigger question is does it really matter? Subtraction and addition have the same precedence in any scientific mathematical operation and are commutable. That is:

x = input - 1 + q;

is the same as

x = input + q - 1;