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

Enyang Mercy
PLUS
Enyang Mercy
Courses Plus Student 2,339 Points

Building Model modify the addContactMethod Not sure of what is needed here

Help please

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) {

    // TODO: Add to the contact method map
  }

  /**
   * 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;
  }

}

3 Answers

Samuel Ferree
Samuel Ferree
31,722 Points

In the method "addContactMethod(String method, String value)" fill in the code that would add the value to the mContactMethods Map.

Remember you add items with the put method

map.put(key, value);
Enyang Mercy
PLUS
Enyang Mercy
Courses Plus Student 2,339 Points

Thanks. Wrote this line of code but still couldnt compile or run the code.

Samuel Ferree
Samuel Ferree
31,722 Points

You don't want to write what I wrote exactly, you want to use the name of your map mContactMethods, with the method string as the key, and the value string as the value.

Here is what you would write for your code

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