Conditional Operator

When the only operation being performed inside of an if and else pair is setting the initial value of a variable, you can use the "conditional operator"1 to perform that assignment instead.

int age = 22;

String message = age < 25 
    ? "You cannot rent a car!"
    : "You might be able to rent a car";

You write a condition followed by a ?, a value to use when that condition evaluates to true, a :, and then a value to use when that condition evaluates to false.

CONDITION ? WHEN_TRUE : WHEN_FALSE
1

Some people will call this a ternary expression. Ternary meaning "three things." Same idea as tres leches.