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Java Java Data Structures - Retired Efficiency! Changing Course

Kenzo Qui
Kenzo Qui
2,350 Points
Posted by Kenzo Qui
Kenzo Qui
2,350 Points

I cannot make this Map method

I cannot solve this problem that is in QuickFix.java and method videosByTitle(). It is aching me! I tried this but it threw that I have a bug ... Error Message: Expected map to contain 23 keys but it contained 1.

com/example/model/Course.java 
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;
  }

}
com/example/model/Video.java 
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;
  }

}
QuickFix.java 
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"

    // TODO(2):  Add the newly created video to the course videos as the second video.

    Video video = new Video("The Beginning Bits");
    course.getVideos().add(1, video);

  }

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

  }

  public Map<String, Video> videosByTitle(Course course) {
    public Map<String, Video> videosByTitle(Course course) {
    Map<String, Video> officialCourse = new HashMap<String,Video>();
    for (Video videos : course.getVideos()) {
      officialCourse.put(course.getName(), videos);
    }
    return officialCourse;
  }

}

1 Answer

Manish Giri
Manish Giri
16,266 Points
Manish Giri
Manish Giri
16,266 Points

Try to follow these steps -

  1. The Course object passed in to the videosByTitlemethod has a getter that will return a List of videos.
  2. Create a new Map object in videosByTitle method.
  3. For each video in the list of videos returned from step 1, add to the map object - the title of the video, and the video itself.
  4. Return the map object.

That should work.

Kenzo Qui
Kenzo Qui
2,350 Points
Kenzo Qui
Kenzo Qui
2,350 Points

I tried it but,,, I'll try again, I might be doing something wrong here. Thanks!!! I'll update you

Kenzo Qui
Kenzo Qui
2,350 Points
Kenzo Qui
Kenzo Qui
2,350 Points

I tried it but it threw that I have a bug Error Message: Expected map to contain 23 keys but it contained 1.

  public Map<String, Video> videosByTitle(Course course) {
    Map<String, Video> officialCourse = new HashMap<String,Video>();
    for (Video videos : course.getVideos()) {
      officialCourse.put(course.getName(), videos);
    }
    return officialCourse;
  }