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

isaac schwartzman
isaac schwartzman
963 Points

Bummer! Expected [pager, phone] from getAvailableContactMethods, but got [(555) 555-5555, (222) 222-2222].

I don't know how else it would want me to return a map with this method

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

import java.util.Map;
import java.util.HashSet;
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.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.
    Set<String> contactMethods = new HashSet <>(mContactMethods.values());
    return contactMethods;
  }

  /**
   * 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;
  }

}
Binyamin Friedman
Binyamin Friedman
14,615 Points

You made a new HashSet with the contact method values. Maps have key-value pairs and they want you to return the keys, not the values. You can use mContactMethods.keySet() to get a set of the keys.

isaac schwartzman
isaac schwartzman
963 Points

Thanks, I had completely forgotten about that method.