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

Posted by lee lewis
lee lewis
Courses Plus Student 5,796 Points

compiler error

its saying cannot find symbol drive... to be honest it just doesnt matter how many times i look at this i just cant figure out the concept... when the guy explains it in the video he speaks really quickly over really important details and uses language thats just far too complicated... on top of this he uses too many complex terms in a row.

can somebody explain this conceptually with some level of clarity so i know what and why this stuff is doing what its doing..

thankyou

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() {
  drive += 1;
  }
  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;
  }

}

1 Answer

Ken Alger
STAFF
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

Lee;

First of all your error is due to the fact that with your code you are using drive in your drive() method as a variable without declaring it anywhere.

  public void drive() {
    drive += 1; // here is the issue. drive is an unknown variable
  }

I wrote a post on this a while back. Not to diminish answering your question directly, but have a look at that post and let me know if you have any further questions.

Happy coding,
Ken