Return True or False Randomly

(Math.random() < 0.5) returns true or false randomly

The class java.util.Random already has this functionality:

public boolean getRandomBoolean() {
    Random random = new Random();
    return random.nextBoolean();
}

However, it's not efficient to always create a new Random instance each time you need a random boolean. Instead, create a attribute of type Random in your class that needs the random boolean, then use that instance for each new random booleans:

public class YourClass {

    /* Oher stuff here */

    private Random random;

    public YourClass() {
        // ...
        random = new Random();
    }

    public boolean getRandomBoolean() {
        return random.nextBoolean();
    }

    /* More stuff here */

}