Shorthand operators Shorthand operators Shorthand operator A shorthand

Shorthand operators

Shorthand operators • Shorthand operator: • A shorthand operator is a shorter way to express something that is already available in the Java programming language • Shorthand operations do not add any feature to the Java programming language (So it's not a big deal).

Shorthand operators +=, -=, *=, /= and *= • A frequent construct is the following: x is a variable in the program x = x + value ; // Add value to the variable x x = x - value ; // Subtract value to the variable x x = x * value ; // Increase the variable x by value times and so on. . . Java has a shorthand operator for these kinds of assignment statements

Shorthand operators +=, -=, *=, /= and *= (cont. ) • Operator assignment short hands: Operator symbol Name of the operator Example Equivalent construct += Addition assignment x += 4; x = x + 4; -= Subtraction assignment x -= 4; x = x - 4; *= Multiplication x *= 4; assignment x = x * 4; /= Division assignment x /= 4; x = x / 4; %= Remainder assignment x %= 4; x = x % 4;

Shorthand operators +=, -=, *=, /= and *= (cont. ) • Exercise: what is printed by the following program public class Shorthand 1 { public static void main(String[] args) { int x; x = 7; x += 4; System. out. println(x); x = 7; x -= 4; System. out. println(x);

Shorthand operators +=, -=, *=, /= and *= (cont. ) x = 7; x *= 4; System. out. println(x); x = 7; x /= 4; System. out. println(x); x = 7; x %= 4; System. out. println(x); } }

Shorthand operators +=, -=, *=, /= and *= (cont. ) • Example Program: (Demo above code) – Prog file: http: //mathcs. emory. edu/~cheung/Courses/170/Syllabus/04/Progs/ Shorthand 1. java • How to run the program: • Right click on link and save in a scratch directory • To compile: javac Shorthand 1. java • To run: java Shorthand 1 (You will see the answers on the terminal)

Increment and decrement shorthand operators • Two very commonly used assignment statements are: 1. x = x + 1; and 2. x = x - 1; x is a variable in the program • Java has shorthand operators to increment and decrement a variable by 1 (one).

Increment and decrement shorthand operators (cont. ) • Increment and decrement operators: Operator symbol Name of the operator Example Equivalent construct ++ Increment x++; x = x + 1; -- Decrement x--; x = x - 1;

Increment and decrement shorthand operators (cont. ) • Exercise: what is printed by the following program public class Shorthand 2 { public static void main(String[] args) { int x; x = 7; x++; System. out. println(x); x = 7; x--; System. out. println(x); } }

Increment and decrement shorthand operators (cont. ) • Example Program: (Demo above code) – Prog file: http: //mathcs. emory. edu/~cheung/Courses/170/Syllabus/04/Progs/ Shorthand 2. java • How to run the program: • Right click on link and save in a scratch directory • To compile: javac Shorthand 2. java • To run: java Shorthand 2 (You will see the answers on the terminal)