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Java

Java Data Structures Efficiency!

I'm stuck with // TODO(2): Add to the course videos as the second video. arrayList to List? I can't just add. It has to be the second. Please someone explain what I'm missing.

import com.example.model.Course;
import com.example.model.Video;

import java.util.Map;

public class QuickFix {

  public void addForgottenVideo(Course course) {
    // TODO(1):  Create a new video called "The Beginning Bits"
         Video video = new Video("The Beginning Bits");

    // TODO(2):  Add to the course videos as the second video.
          video.add(1);
  }

  public void fixVideoTitle(Course course, String oldTitle, String newTitle) {

  }

  public Map<String, Video> videosByTitle(Course course) {
    return null;
  }

}
package com.example.model;

import java.util.List;

public class Course {
  private String mName;
  private List<Video> mVideos; 

  public Course(String name, List<Video> videos) {
    mName = name;
    mVideos = videos;
  }

  public String getName() {
    return mName;
  }

  public List<Video> getVideos() {
    return mVideos;
  }

}
package com.example.model;

public class Video {
  private String mTitle;

  public Video(String title) {
    mTitle = title;
  }

  public String getTitle() {
    return mTitle;
  }

  public void setTitle(String title) {
    mTitle = title;
  }

}

2 Answers

Nicolas Hampton
Nicolas Hampton
44,725 Points

You have to add to the course, not to the video. You're adding video to the course. The way you have it written, you're adding the number one to video, which doesn't make sense.

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher

Remember that its all just object references. Also, remember that there is an overloaded method for add in the List interface