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Java Java Data Structures Efficiency! Add tags to a course

Mayur Lalwani
Mayur Lalwani
1,502 Points
Posted by Mayur Lalwani
Mayur Lalwani
1,502 Points

HOW TO SOLVE IT??????

Totally stuck on this code challenge..NO idea what to do..

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

import java.util.HashSet;
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

    mTags = new HashSet<String>();
  }

  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

Kourosh Raeen
Kourosh Raeen
23,732 Points
Kourosh Raeen
Kourosh Raeen
23,732 Points

For the first task you need to initialize mTags in the constructor. Use the new operator and an implementation of set like HashSet:

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

Also, don't forget to import HashSet.

Mariette Grans
Mariette Grans
4,279 Points

Awesome. I tend to make it more difficult than it really is.