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Java Java Objects (Retired) Harnessing the Power of Objects Helper Methods

jinhwa yoo
jinhwa yoo
10,042 Points

java Objects

Objects -----> it kills me .. I don't know

3 Answers

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,457 Points

It may help to think of an object as a instantiation of a class. Functions or methods defined within the class can be be associated with the class (class functions) or with the object instantiated from the class (instance functions). When programming, a class method is signified with the word "static".

How I approach the solution is to consider the general form for a method, then fill it in based on the task description.

// general method structure 
<access> <returns> <name>(<arguments>) {
    <action code>
    return <result>
}

For the challenge, you are asked to create two helper methods. Let's build it by filling in the sections above based on the task description:

  // Task 1 of 2
  // Create a helper method that returns whether or not the GoKart needs
  // to be charged (<action>)
  // This is asking for a True or False result so return a boolean <(returns)>
  // Make it public (<access>) and name it isBatteryEmpty (<name>).
  // so:
  // access is "public"
  // returns is "boolean"
  // name is "isBatteryEmpty()"
  // arguments is None
  // action code is "GoKart needs charging"
  //    This is determined by "mBarsCount == 0"
  // result is boolean value
  public boolean isBatteryEmpty() {
    // combining the return result and action code
    return mBarsCount == 0;
  }


  // Task 2 of 2
  // Now create a helper method named isFullyCharged (<name>). It should
  // return true (<returns>) if the GoKart is at max capacity (<action code>).
  // so:
  // access is not specified so assume "public"
  // returns is "boolean"
  // name is "isFullyCharged()"
  // arguments is None
  // action code is "GoKart is at max capacity"
  //    This is determined by "mBarsCount == MAX_BARS"
  // 
  public boolean isFullyCharged() {
    // combining the return result and action code
    return mBarsCount == MAX_BARS;
  }

Very Nice Explanation Chris Freeman

jinhwa yoo
jinhwa yoo
10,042 Points

perferct... I understand everything.. now.. omg...