Java Java Data Structures Efficiency! Using a Map to store Contact Methods

this code is not working can some1 explain?

In the next couple of steps, let's fix up this work in progress Contact model. This is going to be used in a Web application where the user can add different ways to contact a person.

In this first step, modify the addContactMethod method to store the information in the mContactMethods Map.

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

import java.util.Map;
import java.util.Set;
import java.util.HashMap;

public class Contact {
  private String mFirstName;
  private String mLastName;
  private Map<String, String> mContactMethods;

  public Contact(String firstName, String lastName) {
    mFirstName = firstName;
    mLastName = lastName;
    /* This stores contact methods by name
     * eg:  "phone" => "(555) 555-1234"
     */
    mContactMethods = new HashMap<String, String>();
  }

  public void addContactMethod(String method, String value) {
    mContactMethods.add(method, value);
  }

  /**
   * Returns the available contact methods.  eg: phone, pager,
   *
   * @return The name of the contact methods that are available
   */
  public Set<String> getAvailableContactMethods() {
    // FIXME: This should return the current contact method names.
    return null;
  }

  /**
   * Returns the value for the contact method if it exists, 
   *
   * @param methodName  The name of the contact method to look up.
   * @return The name of the contact methods that are available
   */
  public String getContactInfo(String methodName) {
    // FIXME: return the value for the passed in *methodName*
    return null;
  }

  public String getFirstName() {
    return mFirstName;
  }

  public String getLastName() {
    return mLastName;
  }

}

2 Answers

Rob Bridges
Rob Bridges
13,602 Points

Hey Admire, I'd be happy to help you with the first part, you did a really good job getting through it and you're super close on getting past it, however when adding items to a map the command is .put()

give

mContactMethods.put(method, value);

a try and see how that works. No big deal, just looks like a little confusion.

Don't hesitate to give me a shout if you have any more questions. Also for the other questions in this challenge I recommend you use this.

Sean M
MOD
Sean M
Treehouse Moderator 7,327 Points

You are calling the mContactMethods, and specifying the string's method and value. Therefore:

 public void addContactMethod(String method, String value) {
    // TODO: Add to the contact method map
    mContactMethods.put(method, value);
  }