Lesson 5 / 38

Operators

Work through Java's arithmetic, comparison and logical operators, short-circuit evaluation, and the pitfalls of integer division and silent overflow.

The common set

+ - * / % for arithmetic, == != < > <= >= for comparison, && || ! for boolean logic (short-circuiting), and +=, ++ style compound assignment.

int a = 7, b = 2;
System.out.println(a / b);    // 3  (integer division!)
System.out.println(a % b);    // 1
System.out.println(a / 2.0);  // 3.5 (one double operand)

Integer overflow is silent

int is 32-bit and wraps around past ~2.1 billion with no error. Use long for large counts, or Math.addExact(...) to get an exception on overflow.