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A more common example of where conditional operators are used is checking for null objects before performing an operation. In the following example, if duck is null, the program will throw a NullPointerException at runtime:

if(duck!=null & duck.getAge()<5) { // Could throw a NullPointerException // Do something }

The issue is that the logical AND (&) operator evaluates both sides of the expression. We could add a second if statement, but this could get unwieldy if we have a lot of variables to check. An easy-to-read solution is to use the conditional AND operator (&&):

if(duck!=null && duck.getAge()<5) { // Do something }

In this example, if duck is null, the conditional prevents a NullPointerException from ever being thrown, since the evaluation of duck.getAge() < 5 is never reached.