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

Carlos Quevedo
Carlos Quevedo
5,911 Points
Posted by Carlos Quevedo
Carlos Quevedo
5,911 Points

Where to put the do/while loop?

I'm kind of stumped on where to put the do/while loop in this exercise. In the tutorial, we put it in Example.java but here, it wants me to write it in the class? This is the last half of what I have written so far and it's returning syntax errors (failure clap! yay! <--- not sarcasm!). Sorry for the messy code formatting:

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

    while wasCharged = false;
    }
    return wasCharged;
    }

  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

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,441 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,441 Points

In task 1, you're asked to make the charge() method only charge while the GoKart is "not fully charged". The while loop goes inside the charge() method.

  // Task 1 of 1
  // 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.

  public void charge() {
    // while the GoKart is not fully charged...
    while (!isFullyCharged()) {
      // increment the current charge
      mBarsCount++;
    }
  }
Carlos Quevedo
Carlos Quevedo
5,911 Points
Carlos Quevedo
Carlos Quevedo
5,911 Points

Ah! I get it now. I thought I had to add a new method for a second. Didn't see that I had to replace the code within the '''charge()''' method with the loop. This makes much more sense. Thanks!

Thomas Domajnko
Thomas Domajnko
607 Points
Thomas Domajnko
Thomas Domajnko
607 Points

Hmm. It didn't work for me. Instead, it gave me 8 errors:

./GoKart.java:25: error: class, interface, or enum expected
  public boolean isBatteryEmpty() {
         ^
./GoKart.java:27: error: class, interface, or enum expected
  }
  ^
./GoKart.java:29: error: class, interface, or enum expected
  public boolean isFullyCharged() {
         ^
./GoKart.java:31: error: class, interface, or enum expected
  }
  ^
JavaTester.java:81: error: cannot find symbol
if (!kart.isBatteryEmpty() || kart.isFullyCharged()) {
         ^
  symbol:   method isBatteryEmpty()
  location: variable kart of type GoKart
JavaTester.java:81: error: cannot find symbol
if (!kart.isBatteryEmpty() || kart.isFullyCharged()) {
                                  ^
  symbol:   method isFullyCharged()
  location: variable kart of type GoKart
JavaTester.java:86: error: cannot find symbol
if (!kart.isFullyCharged()) {
         ^
  symbol:   method isFullyCharged()
  location: variable kart of type GoKart
./GoKart.java:17: error: cannot find symbol
    while (!isFullyCharged()) {
            ^
  symbol:   method isFullyCharged()
  location: class GoKart
8 errors

Ack.