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Java Java Data Structures - Retired Efficiency! Add tags to a course

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

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);