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Java Java Data Structures - Retired Efficiency! Changing Course

Kyle Salisbury
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.a{fill-rule:evenodd;}techdegree
Kyle Salisbury
Full Stack JavaScript Techdegree Student 16,363 Points

3 0f 3 challenge for last Java data structures quiz.

I'm really lost to even know where to begin. Craig gives a hint that I should use the videosByTitle method, but I have no idea how to search for a video title and switch it.

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.TreeMap;

import java.util.ArrayList;
import java.util.Arrays;


public class QuickFix {

  public void addForgottenVideo(Course course) {
    Video newVideo = new Video("What up?");

    course.getVideos().add(1, newVideo);

  }

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


  }

  public Map<String, Video> videosByTitle(Course course) {
   Map<String, Video> byTitle = new TreeMap<String, Video>();


    for (Video video : course.getVideos()) {
            byTitle.put(video.getTitle(), video);
        }
    return byTitle;
  }

}

1 Answer

Christopher Augg
Christopher Augg
21,223 Points

Kyle,

No problem. I will provide you with some pseudocode to get you on track.

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

            // Create a map and assign it the videosByTitle method. Make sure to pass in course.

            // Create a video and assign it using the map's get method. Pass in the oldTitle to get the video we want.

            // set the title of this video to the newTitle using the video's set method

            // use the map's put method to place the newTitle and video back into the map

  }

Please let me know if this helps. I will explain it in more detail if you need.

Regards,

Chris

Dustin Bryce Flanary
Dustin Bryce Flanary
17,663 Points

I'm having a hard time knowing what parameters to put into the map I create. I assume course and string?