The logical operators for AND (&&) and OR (||) are used to combine simple relational statements into more complex expressions. The NOT (!) operator is used to negate a boolean statement.
Original Processing.org Example: LogicalOperators
// All Examples Written by Casey Reas and Ben Fry // unless otherwise stated. size(200, 200); background(126); boolean op = false; for(int i=5; i<=195; i+=5) { // Logical AND stroke(0); if((i > 35) && (i < 100)) { line(5, i, 95, i); op = false; } // Logical OR stroke(76); if((i <= 35) || (i >= 100)) { line(105, i, 195, i); op = true; } // Testing if a boolean value is "true" // The expression "if(op)" is equivalent to "if(op == true)" if(op) { stroke(0); point(width/2, i); } // Testing if a boolean value is "false" // The expression "if(!op)" is equivalent to "if(op == false)" if(!op) { stroke(255); point(width/4, i); } }