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Last modified: September 7, 2019

In this short tutorial, we're going to learn about the Java *XOR* operator. We'll go through a bit of theory about *XOR* operations, and then we'll see how to implement them in Java.

Let's begin with a little reminder of the semantics of the *XOR* operation. **The XOR logical operation, or exclusive or, takes two boolean operands and returns true if and only if the operands are different.** Thus, it returns false if the two operands have the same value.

So, the *XOR* operator can be used, for example, when we have to check for two conditions that can't be true at the same time.

Let's consider two conditions, *A* and *B.* Then the following table shows the possible values of *A XOR B*:

**The A XOR B operation is equivalent to (A AND !B) OR (!A AND B).** Parentheses have been included for clarity, but are optional, as the

Now, let's see how to express the *XOR* operation in Java. **Of course, we have the possibility to use the && and || operators, but this can be a bit wordy**, as we're going to see.

Imagine a *Car* class having two *boolean* attributes: *diesel* and *manual*. And now, let's say we want to tell if the car is either diesel or manual, but not both.

Let's check this using the *&&* and *||* operators:

Car car = Car.dieselAndManualCar(); boolean dieselXorManual = (car.isDiesel() && !car.isManual()) || (!car.isDiesel() && car.isManual());

**That's a bit long, especially considering that we have an alternative — the Java XOR operator, represented by the ^ symbol.** It's a bitwise operator — that is, an operator comparing the matching bits of two values in order to return a result. In the

So, instead of our cumbersome *XOR* implementation, we can directly use the *^* operator:

Car car = Car.dieselAndManualCar(); boolean dieselXorManual = car.isDiesel() ^ car.isManual();

As we can wee, the *^* operator allows us to be more concise in expressing *XOR* operations.

**Finally, it's worth mentioning that the XOR operator, like the other bitwise operators, works with every primitive type.** For example, let's consider two integers 1 and 3, whose binary representations are 00000001 and 000000011, respectively. Then, using the

assertThat(1 ^ 3).isEqualTo(2);

Only the second bit is different in those two numbers, therefore the result of the *XOR* operator on this bit will be 1. All other bits are identical, thus their bitwise *XOR* result is 0, giving us a final value of 00000010 — the binary representation of the integer 2.

In this article, we learned about the Java *XOR* operator. We saw that it offers a concise way to express *XOR *operations.

As usual, the full code of the article can be found over on GitHub.

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