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Java Java Data Structures - Retired Efficiency! Changing Course

Posted by Nirbhay Agarwal
Nirbhay Agarwal
2,852 Points

Cannot find the symbol error

You can use the same list used in different class referencing it with the same name

List<Video> mVideos Im using this List of Course class

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) {
    List<Video> mVideos = new ArrayList<>();
    for(mVideos video : videos) {
    video.addVideo("The Beginning Bits");
    video.add(1, video);
    } 
    // 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.

  }

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

  }

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

}
Nirbhay Agarwal
Nirbhay Agarwal
2,852 Points

The access specifer is private it can only be accessed in the same class

2 Answers

J.D. Sandifer
J.D. Sandifer
18,813 Points
J.D. Sandifer
J.D. Sandifer
18,813 Points

The problem is in your QuickFix class:

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

import java.util.Map;

public class QuickFix {

  public void addForgottenVideo(Course course) {
    // I removed your stuff here...

    // TODO(1):  Create a new video called "The Beginning Bits"
    // Create a new video using the "new" syntax (replacing <> values with appropriate names):
    Video <name> = new Video("<title>");

    // TODO(2):  Add the newly created video to the course videos as the second video.
    // Use the getVideos() method from the Course class to get a reference to the course 
    // video list (replace <> with a name for the reference). Then you can add the new video to the list.
    List<Video> <name> = course.getVideos();

    // Add code to add your video here.


  }

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

  }

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

}
Nirbhay Agarwal
Nirbhay Agarwal
2,852 Points
Nirbhay Agarwal
Nirbhay Agarwal
2,852 Points

I got it thank

List<Video> videoList = course.getVideo();
Video video = new Video("The Beginning Bits");
videoList.add(1, video);