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

olu adesina
olu adesina
23,007 Points

Map.Entry.getKey() returning type Object instead of the key corresponding to this entry.

Map.Entry.getKey() is returning type object isn't it meant to return the key which can be any type im expecting a string but it returns an object

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) {

    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> keys = new HashSet<String>();
    for(Map.Entry entry : mContactMethods.entrySet()){
      String key = entry.getKey();  
      keys.add(key);
    }
    return keys;
  }


  /**
   * 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;
  }

}