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Java Java Data Structures Efficiency! Add tags to a course

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

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.

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