Language Basics: Operators

Question 1

What does the ternary operator ?: operator do?

Answer 1

This operator is also known as the ternary operator because it uses three operands. If first operand is true, then do second operand. Otherwise, do third operand.

Question 2

What does the instanceof operator do?

Answer 2

The instanceof operator compares an object to a specified type. You can use it to test if an object is an instance of a class, an instance of a subclass, or an instance of a class that implements a particular interface.

Question 3

What is the difference between prefix (++i) and postfix(i++)?

Answer 3

++i will give the result of the new i.

i++ will give the result of the original i and store the new i for the next action.

Question 4

What does the unary bitwise complement operator ~ do?

Answer 4

Inverts a bit pattern; it can be applied to any of the integral types, making every “0” a “1” and every “1” a “0”. For example, a byte contains 8 bits; applying this operator to a value whose bit pattern is “00000000” would change its pattern to “11111111”.

Question 5

result -= 1;

Answer 5

Result = result - 1;

Question 6

result *= 2;

Answer 6

result = result*2;