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

Jeremy Nash
PLUS
Jeremy Nash
Courses Plus Student 2,250 Points
Posted by Jeremy Nash
Jeremy Nash
Courses Plus Student 2,250 Points

Increments and Decrements Im absolutely lost

Okay, so let's use our new isFullyCharged helper method to change our implementation details of the charge method. Let's make it so it will only charge until the battery reports being fully charged. Let's use the ! symbol and a while loop. Inside the loop increment mBarsCount

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() {
    return mBarsCount == MAX_ENERGY_BARS;
  }

}

3 Answers

Dennis Mårtensson
Dennis Mårtensson
7,400 Points
Dennis Mårtensson
Dennis Mårtensson
7,400 Points

It's asking you to rewrite the charge()-method so it will increment 'mBarsCount' variable one step at a time until it is fully charged. Like this;

public void charge() {
    while (!isFullyCharged()){
      mBarsCount++; 
    }
  }

So, while the battery is NOT (hence the ! symbol) fully charged, increment (as in, add 1 to the existing value of) 'mBarsCount', then check again if it is fully charged. Repeat until '(!isFullyCharged())' returns false (as in, it is fully charged).

Lindsay Sauer
Lindsay Sauer
12,029 Points
Lindsay Sauer
Lindsay Sauer
12,029 Points

We're wanting to keep checking to see if the battery's been charged yet, so you want to continuously check the value returned by isFullyCharged() until you receive true and the battery is charged. If it's not charged, it asks us to increment the value of mBarsCount:

while (!isFullyCharged()) {
  mBarsCount++;
}
Jeremy Nash
PLUS
Jeremy Nash
Courses Plus Student 2,250 Points
Jeremy Nash
Jeremy Nash
Courses Plus Student 2,250 Points

thanks to both of you gave me some clarity on what was asked and hopefully wont have the same problem later on