Why &= operator doesn't work the same as &&

I'm just curious how java works. Can someone explain why getBoolean is called in Case 1 and not called in Case 2?

public class Main {

    public static void main(String[] args) {
        System.out.println("---------- Case 1 ----------");
        boolean b = false;
        b &= getBoolean(true);

        System.out.println("---------- Case 2 ----------");
        b = false;
        b = b && getBoolean(true);
    }

    private static boolean getBoolean(boolean bool) {
        System.out.println("getBoolean(" + bool + ") was calledn");
        return bool;
    }

}

Output:

---------- Case 1 ----------
getBoolean(true) was called

---------- Case 2 ----------

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b &= a is a shortcut to b = b & a not to b = b && a

It is because of the difference between & and && operators.

The & operator always evaluates both sides of conditions.

The && operator evaluates the second only if needed.

So, getBoolean(true) will not run in the 2nd case.

---

In Case 2 getBoolean(true); is not evaluated, because the && is a short-circuit operator, eg if the expression will be false it stops evaluating

Case 1 just sets the result of the getBoolean() method to the b variable.

---

Update, thanks to @KisHan:

Note that b &= a is equal to b = b & a and not b = b && a

---

In second case b is false and for && if first condition is false it won't move ahead.

 b = b && getBoolean(true);//b is false

So && (Logical AND) first checks the left side of the operation, if it's true than it continues to the right side.

While & (Bitwise AND) operator evaluates both sides of expression as it's bitwise AND operator.As it performs AND operation between leftside and right side.

So in first case it will be

b = b & getBoolean(true);//will perform AND operation to evaluate Expression

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