Debug Trace

A debug flag can print intermediate values while leaving the final result unchanged.

DebugTrace.java

public class DebugTrace {
    public static void main(String[] args) {
        boolean debug = ;
        int width = 6;
        int height = 4;
        int area = width * height;

        if (debug) {
            System.out.println("debug width=" + width + " height=" + height);
        }

        System.out.println("area=" + area);
    }
}

public class DebugTrace {
    public static void main(String[] args) {
        boolean debug = ;
        int width = 6;
        int height = 4;
        int area = width * height;

        if (debug) {
            System.out.println("debug width=" + width + " height=" + height);
        }

        System.out.println("area=" + area);
    }
}

debug flag A flag lets diagnostic output be turned on or off without changing the calculation.

intermediate value Printing the intermediate values helps confirm how the result was built.