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Java Java Data Structures Efficiency! Changing Course

Posted by Kenneth Phillips
Kenneth Phillips
Courses Plus Student 10,188 Points

Changing Course

Error :

./QuickFix.java:12: error: cannot find symbol course.add(1, video); ^ symbol: method add(int,Video) location: variable course of type Course 1 error

I don't see what the problem is because that is how you add to a list on a specific spot. So what is the problem?

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"
   Video video = new Video("The Beginning Bits");
    // TODO(2):  Add the newly created video to the course videos as the second video.
    course.add(1, video);
  }

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

  }

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

}
Miguel Rivas
Miguel Rivas
4,902 Points
Miguel Rivas
Miguel Rivas
4,902 Points

Hi Kenneth, try importing the list at the beginning of the method 'addForgottenVideo' that Craig made for you.

That way you have a list to add it, right now I believe you are not using any list.

//add this:
List<Video> videoList = course.getVideos();

// 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.add(1, video);

Edit: sorry, you can't add a video to a 'course' list, you need to add it to a videoList, fix that also:

videoList.add(1,video);

PS: don't forget your imports:

import java.util.List;

Have a great day.

M.