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

Help me on this

https://docs.oracle.com/javase/7/docs/api/java/util/Map.html i used this link but cant get it correct

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.put(method,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 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*
    return mPager;
  }

  public String getFirstName() {
    return mFirstName;
  }

  public String getLastName() {
    return mLastName;
  }

}

1 Answer

Allan Clark
Allan Clark
10,810 Points
  public String getContactInfo(String methodName) {
    // FIXME: return the value for the passed in *methodName*
    return mPager;
  }

Need to change the return statement. Try using the .get() method on the Map.

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

Allan Clark
Allan Clark
10,810 Points

pager was just an example of what argument may be passed to the methodName parameter. Use this return statement.

return mContactMethods.get(methodName);

u are a star

Allan Clark
Allan Clark
10,810 Points

Just glad I could help. May the Java force be with you! :)