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Java Java Objects (Retired) Harnessing the Power of Objects Incrementing

Posted by Natenda Manyau
Natenda Manyau
3,005 Points

Increment Decrement Challenge

Hello. Am not too sure on where to put the while loop on this question. i also keep getting errors on the code I've written. please help.

GoKart.java 
public class GoKart {
  public static final int MAX_ENERGY_BARS = 8;
  private String mColor;
  private int mBarsCount;

  public GoKart(String color) {
    mColor = color;
    mBarsCount = 0;
  }

  public String getColor() {
    return mColor;
  }

  public void charge() {
    mBarsCount = MAX_ENERGY_BARS;
  }

  public boolean isBatteryEmpty() {
    return mBarsCount == 0;
  }

  public boolean isFullyCharged() {
    boolean isFullyCharged = false;
    if(!isFullyCharged()){
    mBarsCount++;
      isFullyCharged = true;
    return mBarsCount == MAX_ENERGY_BARS;
      }

   }

}

3 Answers

Ken Wagner
Ken Wagner
7,298 Points
Ken Wagner
Ken Wagner
7,298 Points

Hello! Remember to double check what is being asked in the challenge. You will need to use a "while" loop, not an "if" statement. Also challenge wants you to put your loop in the "charge" method. You have it in the "isFullyCharged" method. You were closer than you think.

remove:

boolean isFullyCharged = false;
    if(!isFullyCharged()){
    mBarsCount++;
      isFullyCharged = true;

try:

public void charge() {

          while(!isFullyCharged()) {
          mBarsCount++;
         }
  }
William Li
PLUS
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points

Hi, Natasha, a while ago, someone else asked almost the exact same question, even the code he's written is quite similar to yours. You can find the answer to that post here. https://teamtreehouse.com/forum/trying-to-use-a-helper-method-to-change-implementation-details-for-a-method-i-need-to-use-and-a-while-loop

Jess Sanders
Jess Sanders
12,086 Points
Jess Sanders
Jess Sanders
12,086 Points

Use the following snippet of code as your example to follow in changing the implementation details of the charge method:

public boolean dispense() {
    boolean wasDispensed = false;
    if (!isEmpty()) {
      mPezCount--;
      wasDispensed = true;
    }
    return wasDispensed;
  }
  • Instead of if, use while
  • increment, rather than decrement
  • The charge method doesn't need to return a boolean, so ignore all of the code involving the boolean wasDispensed

Keep isFullyCharged as it was from the previous challenge.

  public boolean isFullyCharged() {
    return mBarsCount == MAX_ENERGY_BARS;
  }