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Java Java Objects Harnessing the Power of Objects Increment and Decrement

Abel Sun
Abel Sun
479 Points

I have no idea what i suppose to do..

i did watch the video but still don't understand what is it about. The question is : In your newly created drive method, increment the new lapsDriven variable by 1. Use the incrementing shorthand to increase lapsDriven.

class GoKart {
  public static final int MAX_BARS = 8;
  private String color;
  private int barCount;

  public GoKart(String color) {
    this.color = color;

  public String getColor() {
    return color;

  public void charge() {
    barCount = MAX_BARS;

  public boolean isBatteryEmpty() {
    return barCount == 0;

  public boolean isFullyCharged() {
    return MAX_BARS == barCount;

  private int lapsDriven;

1 Answer

Rich Zimmerman
Rich Zimmerman
24,062 Points

The shorthand or incrementing and decrementing is pretty consistent across programming languages. it's simply

lapsDriven++; // will increment by 1
lapsDriven--; // will decrement by 1

If you want to add or subtract values, there's a shorthand for that as well

lapsDriven += 5;
lapsDrive -= 5;