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Java Java Objects (Retired) Harnessing the Power of Objects Method Signatures

Posted by MUZ140151 Gilbert Chapara
MUZ140151 Gilbert Chapara
2,621 Points

harnessing the power of objects

I have added a method drive that defines a parameter laps. These high-powered GoKarts use 1 energy bar off their battery per lap. Using method signatures, add a new default method called drive that performs just 1 lap and takes no arguments.

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

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

  public String getColor() {
    return mColor;
  }

  public void drive(int laps) {
    // Other driving code omitted for clarity purposes
    mBarsCount -= laps;
  }

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

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

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

}
Tom Schinler
Tom Schinler
21,052 Points
Tom Schinler
Tom Schinler
21,052 Points

Are you just looking for the answer or are you not understanding the task at hand and looking for hints and a breakdown?

The task is looking for you to create a default method that runs 1 lap. The method should be made available to other classes, and return nothing.

Gloria Dwomoh
Gloria Dwomoh
13,116 Points

MUZ140151 Chapara Try posting your effort ie. how you tried to solve it. So that others can be able to help you better :)

Spencer Saunders
Spencer Saunders
1,981 Points

I'm not understanding this concept either. If somebody could please help me, it would be much appreciated.

Thomas Biddulph
Thomas Biddulph
2,184 Points
Thomas Biddulph
Thomas Biddulph
2,184 Points

Pay special attention to these statements: GoKarts use 1 energy bar off their battery per lap, Using method signatures, add a new default method called drive that performs just 1 lap and takes no arguments.

In other words, write a new drive method with no parameters that decrements (decreases by 1) mBarsCount.

2 Answers

Victor Levytskiy
Victor Levytskiy
7,608 Points
Victor Levytskiy
Victor Levytskiy
7,608 Points

You just need to create a drive method in which you call drive method with parameter

public void drive()
{
   drive(1);
}
Pavel Piskunov
Pavel Piskunov
2,410 Points
Pavel Piskunov
Pavel Piskunov
2,410 Points

Why it works? We have two methods with same name. Why Java compiler not change stuff in method, when you declare it in second time, or get an error?

Andrew Winkler
Andrew Winkler
37,739 Points
Andrew Winkler
Andrew Winkler
37,739 Points

We are looking to "perform" a method called drive that takes 1 lap with no arguments. It is considered a public method and it is not looking to return anything either so public void starts of the method notation:

public void drive() { drive(1); }

To break it down piece by piece: It's a public function/ that doesn't return anything/ where drive is the method name/ takes no arguments/ and it runs the other method signature (taking 1 lap as the parameter).