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

Posted by Matthew Earlywine
Matthew Earlywine
2,560 Points

For this task, let's fix the getContactInfo

Not sure where the methodName.

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
    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*
    return null;
  }

  public String getFirstName() {
    return mFirstName;
  }

  public String getLastName() {
    return mLastName;
  }

}

4 Answers

Rob Bridges
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 Points
Rob Bridges
.a{fill-rule:evenodd;}techdegree seal-36
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 Points

Hey Matthew,

For this method they are wanting us to call the get() method on mContactMethods and passing in methodName from the method argument.

So it would look something like below.

return mContactMethods.get(methodName);
Gonzalo Torres del Fierro
PLUS
Gonzalo Torres del Fierro
Courses Plus Student 16,751 Points
Gonzalo Torres del Fierro
Gonzalo Torres del Fierro
Courses Plus Student 16,751 Points

every question related to this challenge (from 1 to 3 ) is very well explained on Maps16:07 with Craig Dennis video.

ben rodriguez
ben rodriguez
6,382 Points
ben rodriguez
ben rodriguez
6,382 Points

i added an

if (methodName != Null) {

   return mContactMethods.get(methodName);

}

mongst
mongst
10,841 Points
mongst
mongst
10,841 Points

This worked for me:

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
    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*
    return null;
  }

  public String getFirstName() {
    return mFirstName;
  }

  public String getLastName() {
    return mLastName;
  }

}