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Java Java Objects Harnessing the Power of Objects Overload Methods

Create a new method named drive that accepts no arguments. It should call the newer drive method passing in a 1 for the

No idea what I am doing wrong here. Can some one explain to me what I am missing

GoKart.java
class GoKart { 
  public static final int MAX_BARS = 8; 
  private String color; private int barCount; 
  private int 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 int drive(int laps) { 
    drive(1);
  }

2 Answers

Hi there,

You should end up with two `drive methods. One takes an integer parameter and adjusts the barCount and lapsDriven variables by the amount passed in. Task one says Modify the drive method to define a parameter of how many laps should be driven. Update the method body to handle the new parameter.

So, add am integer parameter in the method heading and inside the method reduce barCount by that integer and increase lapsDriven by the same number.

Task 2 says Create a new method named drive that accepts no arguments. It should call the newer drive method passing in a 1 for the default. So you're creating a new method, leaving the other one in place. This method doesn't take a parameter and nor does it return anything. Inside the method, call the drive method from task one and pass in the value 1 as the number of laps to drive.

This way, you end up with two drive methods, one takes a parameter, the other doesn't. Neither return anything.

I hope that helps,

Steve.

class GoKart { public static final int MAX_BARS = 8; private String color; private int barCount; private int 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--; } public void drive() { //This function make the cart run one lap drive(1);
}

public void drive(int laps) { if(laps > barCount) { throw new IllegalArgumentException("Not enough energy bars!"); } lapsDriven += laps; barCount -= laps; } }