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Java Java Data Structures - Retired Efficiency! Changing Course

What is the error

this is what it says: ./QuickFix.java:13: error: cannot find symbol

List

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 to the course videos as the second video.
    List<Video> videoList = new ArrayList<Video>();
    videoList.add(1, video);
  }

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

  }

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

}

1 Answer

Dan Johnson
Dan Johnson
40,533 Points

You'll need to update your imports to help the compiler find the definitions:

import java.util.List;
import java.util.ArrayList;

Then you'll want to change how you're creating the updated list. Since you're adding a video to the course's list you'll want to grab that collection instead of creating a new one:

// Get the videos from the course passed in
List<Video> videoList = course.getVideos();