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

Todd Anderson
Todd Anderson
4,259 Points

I'm not sure how to solve task 3. I have tried everything I could think of and re-watched the video several times. :/

I thought it would be simple. If they type in the method, return the value associated with that method.

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

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

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) {
    // TODO: Add to the contact method map
    mContactMethods.put(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 mContactMethods.keySet();
  }

  /**
   * 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*
    for (String value : mContactMethods.keySet()){
      if (methodName.equals(mContactMethods.getKey()){

      }}
    return value;

  }

  public String getFirstName() {
    return mFirstName;
  }

  public String getLastName() {
    return mLastName;
  }

}

2 Answers

Yanuar Prakoso
Yanuar Prakoso
13,610 Points

HI Todd

You only need to .get the value of corresponding methodName key. You do not need to iterate using for loops.

I tried to solve your challenge and here is the code I used:

public String getContactInfo(String methodName) {
    // FIXME: return the value for the passed in *methodName*
    return mContactMethods.get(methodName);
  }

I hope this can help you a little

Todd Anderson
Todd Anderson
4,259 Points

Thank you. I actually solved it already, but I couldn't figure out how to remove my post. I really appreciate the help and hopefully it will help others if they get stuck.

Tojo Alex
PRO
Tojo Alex
Pro Student 13,331 Points

You can not remove posts when they have been answered (by that I mean if someone else has posted on your question).