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

Having trouble with the "hasTag" method in Course.java.

I have tried several different solutions for the "hasTag" method problem, but none have worked. I have used the .contains method from the Set class and also the .contains method. Most recently, as you'll see below, I tried using an if-else statement and that didn't work. I deleted the else part of the statement and decided to give up and ask the forum. The current answers in the forum didn't help me with question 3 of the problem. Can someone help me find a good solution? I've gotten this far in the java training without getting stuck and finally hit a road block :( Thanks for any help you can give!

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

import java.util.List;
import java.util.Set;
import java.util.HashSet;
import java.util.ArrayList;

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

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

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

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

  public boolean hasTag(String tag) {
    // TODO: Return whether or not the tag has been added
    if (mTags.contains(tag)) {
     System.out.println("Tag already exists");

    }
    return false;

  }

  public String getTitle() {
    return mTitle;
  }


}

1 Answer

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher

What if you return the result of that expression?

This seemed to fix it:

public boolean hasTag(String tag) {
    // TODO: Return whether or not the tag has been added
      if (!mTags.contains(tag)) {
     return false;
      }
    return true;
  } 

Although I'm sure there's a much better way. I have a long way to go to truly understand the syntax. Thanks for your help Craig! I really enjoy your teaching.

Sincerely, Micah Green

Craig Dennis
Craig Dennis
Treehouse Teacher

Remember you can return the result of an expression like so:

return mTags.contains(tag);

Even better! Thanks again Craig!