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Java Java Data Structures Efficiency! Add tags to a course

Posted by Gabriel E
Gabriel E
8,916 Points

How do I add a new Tag?

Hi there,

I'm on this 3-part challenge, and I'm not sure of any of the steps. I've been doing some new pretty challenging code for me and wondering if you could help. Thanks!

com/example/model/Course.java 
package com.example.model;

import java.util.List;
import java.util.Set;

public class Course {
  private String mTitle;
  private Set<String> mTags;

  public Course(String title) {
    mTitle = title;
    // TODO: initialize the set mTags
  }

  public void addTag(String tag) {
    // TODO: add the tag
  }

  public void addTags(List<String> tags) {
    // TODO: add all the tags passed in
  }

  public boolean hasTag(String tag) {
    // TODO: Return whether or not the tag has been added
    return false;
  }

  public String getTitle() {
    return mTitle;
  }

}

1 Answer

Cory Madden
Cory Madden
7,120 Points
Cory Madden
Cory Madden
7,120 Points

First you have to initialize the mTags Set. This means give it the initial value. Do this in the constructor function

public Course(String title){
  // Make sure to import TreeSet
  mTags = new TreeSet<>();
}

To add to the mTags set just use the add method:

mTags.add(tag);