Java Java Data Structures Efficiency! Changing Course

Felipe Murillo
Felipe Murillo
3,605 Points

not sure if I'm updating the map correctly. Any hints?

I'm getting the video using the old key and then putting the same video with the new key and then erasing the old key. Is this approach wrong?

Thanks!!

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;
import java.util.HashMap;
import java.util.List;

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 the newly created video to the course videos as the second video.
   course.getVideos().add(1,video);

  }

  public void fixVideoTitle(Course course, String oldTitle, String newTitle) {
    Video v;
    Map<String, Video> vtmap; 

    vtmap= videosByTitle(course);
    v= vtmap.get(oldTitle);
    vtmap.put(newTitle, v);
    vtmap.remove(oldTitle);
  }

  public Map<String, Video> videosByTitle(Course course) {
    Map<String, Video> vtMap= new HashMap<>();
    List<Video> videosList;

    videosList= course.getVideos();
    for (Video v: videosList){
      vtMap.put( v.getTitle(), v);
    }

    return vtMap;
  }

}