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Java Java Objects Harnessing the Power of Objects Increment and Decrement

Posted by Armando Escarcega
Armando Escarcega
537 Points

For this final task, in your drive method, decrement the battery's status that we maintain in the private field barCount

what am i supose to do

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

  public void drive() { 
    lapsDriven++;        
  }

  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;
  }
}

4 Answers

Joseph Wasden
Joseph Wasden
20,406 Points
Joseph Wasden
Joseph Wasden
20,406 Points

This one is pretty straight forward. You have already incremented successfully by using the increment short hand of the variable name followed by a double-plus sign (for example, lapsDriven++). We just need to declare the shorthand of a decrement using the barCount variable in the same method.

public void drive() {
    lapsDriven++;
    barCount--; // <-- note the decrement notation here
  }
Nourez Rawji
Nourez Rawji
3,303 Points
Nourez Rawji
Nourez Rawji
3,303 Points

Basically, what they want you to do is is have the barCount variable decrease whenever you drive (which also increases the lapsDriven variable. Take a look at your drive() method, that's where you have to make the changes. Let me know if that helps, or if not I can help you out a little more specifically, but you're so close to getting it yourself I think a hint might just be enough.

Muhammad Asif
PLUS
Muhammad Asif
Courses Plus Student 557 Points
Muhammad Asif
Muhammad Asif
Courses Plus Student 557 Points

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

public void drive() { lapsDriven++;
}

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; } public void drive() { lapsDriven++; barCount--; // <-- note the decrement notation here } }