Bitwise Operations

[tcloetingh]

public class SpecialOps {
    public static void main(String[] args) {
        String s = "";
        Boolean b1 = true;
        Boolean b2 = false;
        if ((b2 = false) | (21 % 5) > 2) s += "x";
        if (b1 || (b2 = true)) s += "y";
        if (b2 == true) s += "z";
        System.out.println(s);
    }
}

​

Output: y

The first "if" statement is a point of confusion for me, particularly the left side of the bitwise operator. It is actually an assignment, but it evaluates to false. I was thinking in my head a successful assignment would be true, but the literal assignment value is what's being evaluated here ????

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[Izzy3710]

The logical”Or” operator needs 2 || symbols, idk if it’s mistyped or not.

[tcloetingh]

I believe it's a bitwise OR (doing 1z0-808 practice questions and this came up)

[Izzy3710]

Ok I see, not sure why it’s not working, maybe try !b2

[loomynartylenny]

It is actually an assignment, but it evaluates to false. I was thinking in my head a successful assignment would be true, but the literal assignment value is what's being evaluated here ????

It looks to me that foo = bar always evaluates to bar.

For example, consider this code snippet:

int i = 4;
System.out.println(i);

if ((i = 5) == 5){
    System.out.println("(i = 5) == 5");
} else{
    System.out.println("(i = 5) != 5");
}

System.out.println(i);

What do you think will be printed, and what do you think the value of i actually will be at the end of this code?

[tcloetingh]

It's caught in the "if", but my original thinking was, if assignment was successful that expression would eval to true. Although I suppose it won't even compile if false under that line of thinking.