Magpie Chatbot Lab

Section 2.29 Magpie Chatbot Lab

This is the original College Board Magpie lab from 2014. There is a new Magpie 2.0 lab as of 2025 which is available in the AP Classroom. It is very similar to the following lab, but must be done within AP Classroom. You can use Runestone active codes below or in a Runestone assignment as your IDE to do Magpie 2.0 coding activities as described in the AP Classroom.

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For the original Magpie lab, here is the College Board Magpie Chatbot Lab Student Guide. See https://apcentral.collegeboard.org/courses/ap-computer-science-a/classroom-resources/lab-resource-page for all of the 2014 and 2019 College Board labs.

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The Magpie lab creates a simple chatbot and provides practice with String methods and conditionals. A chatbot is a computer program that tries to hold a conversation with a user. The exercises below will walk you through the activities in the original Magpie chatbot lab.

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Section 2.29.1 Activity 1: Exploring Chatbots

The first activity in Magpie is to explore some existing chatbots. We encourage you to work in pairs or groups on this activity.

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Working in pairs or groups, try out some chatbots, for example:
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- ELIZA the therapist bot from the 1970s:
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- A.L.I.C.E. from the 1990s:
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- Modern chatbots which use AI and machine learning
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Record the chatbot response to each of the following.
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- Where do you come from?
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- asdfghjkl;
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- My mother and I talked last night.
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- The weather is nice.
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- I said no!
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Ask the chatbot other questions.
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- Record the most interesting response.
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- Record the most peculiar response.
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Work with another student or group to have two chatbots chat with each other. Type the responses from one chatbot into the input area for the other and vice-versa.
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Keywords: Some chatbots look for particular keywords and respond based on those keywords. What are some of the keywords that your chatbot seems to be responding to? Why do you think it responds to those keywords?
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Section 2.29.2 Activity 2: Running Simplified Magpie Code

The College Board activity asks you to enter input using the Scanner class and record the responses. But, instead you can run this simplified version below and just call the getResponse method with each string as input as shown in the main method below.

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In this lab, the main method creates a Magpie object called maggie, and calls its methods maggie.getGreeting() and maggie.getResponse(input) where the input can be one of the following strings as input and a response is printed out.

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My mother and I talked last night.
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I said no!
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The weather is nice.
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Do you know my brother?
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Run the following code and see the responses to these 4 inputs.

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When different methods are called from the main method, the control flows to these methods and then comes back to main exactly where it was left when the methods finish. Click on the cool Java visualizer Chatbot below to step through the code. Click on the Forward button at the bottom of the code to step through the code to see the flow of control from the main method to the other methods and back.

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You can also run a version of the Magpie lab on this JuiceMind IDE or on replit.com that uses the Scanner class for input so that you can type in your own input to interact with it.

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As you can see the getResponse method of Magpie2 looks for certain keywords like "mother" and "brother". Why do you think the response to “Do you know my brother?” isn’t “Tell me more about your family.”? Discuss this with partner in pairs and see if you can figure it out.

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The response to “The weather is nice.” is one of the random responses. Look at the code to see how the if statement assigns a value to the response and returns that response. The method getRandomResponse generates a random number and uses that to assign the response. Modify the code above to add other random responses.

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Activity 2.29.1.

Run to see the results. Try changing the input in main.

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public class Magpie2
{
    public String getGreeting()
    {
        return "Hello, let's talk.";
    }

public String getResponse(String statement)
    {
        String response = "";
        if (statement.indexOf("no") >= 0)
        {
            response = "Why so negative?";
        } else if (statement.indexOf("mother") >= 0
                || statement.indexOf("father") >= 0
                || statement.indexOf("sister") >= 0
                || statement.indexOf("brother") >= 0)
        {
            response = "Tell me more about your family.";
        }
        else
        {
            response = getRandomResponse();
        }
        return response;
    }

private String getRandomResponse()
    {
        final int NUMBER_OF_RESPONSES = 4;
        double r = Math.random();
        int whichResponse = (int) (r * NUMBER_OF_RESPONSES);
        String response = "";

if (whichResponse == 0)
        {
            response = "Interesting, tell me more.";
        }
        else if (whichResponse == 1)
        {
            response = "Hmmm.";
        }
        else if (whichResponse == 2)
        {
            response = "Do you really think so?";
        }
        else if (whichResponse == 3)
        {
            response = "You don't say.";
        }
        return response;
    }

public static void main(String[] args)
    {
        Magpie2 maggie = new Magpie2();

System.out.println(maggie.getGreeting());
        System.out.println(">My mother and I talked last night.");
        System.out.println(
                maggie.getResponse("My mother and I talked last night."));
        System.out.println(">I said no.");
        System.out.println(maggie.getResponse("I said no!"));
        System.out.println(">The weather is nice.");
        System.out.println(maggie.getResponse("The weather is nice."));
        System.out.println(">Do you know my brother?");
        System.out.println(maggie.getResponse("Do you know my brother?"));
    }
}
====
// should pass if/when they run code
import static org.junit.Assert.*;

import org.junit.*;

import java.io.*;

public class RunestoneTests extends CodeTestHelper
{
    @Test
    public void testMain() throws IOException
    {
        String output = getMethodOutput("main");
        String expect = "Hello, let's talk....";
        boolean passed = getResults(expect, output, "Expected output from main", true);
        assertTrue(passed);
    }
}

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Subsection 2.29.2.1 Exercises

Alter the code above or in your own IDE (see section below) to do the following. We encourage you to work in pairs.

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Have it respond “Tell me more about your pets” when the statement contains the word “dog” or “cat”. For example, a possible statement and response would be:
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- Statement: I like my cat Mittens.
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- Response: Tell me more about your pets.
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Have it respond favorably when it sees the name of your teacher. Be sure to use appropriate pronouns! For example, a possible statement and response would be:
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- Statement: Mr. Finkelstein is telling us about robotics.
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- Response: He sounds like a good teacher.
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Have the code check that the statement has at least one character. You can do this by using the trim method to remove spaces from the beginning and end, and then checking the length of the trimmed string. If there are no characters, the response should tell the user to enter something. For example, a possible statement and response would be:
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- Statement:
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- Response: Say something, please.
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Add two more noncommittal responses to the possible random responses.
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Pick three more keywords, such as “no” and “brother” and edit the getResponse method to respond to each of these.
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What happens when more than one keyword appears in a string? Try the input My **mother** has a **dog** but **no** cat. Which response did you get – was it the one about family or the one about pets or the negative one for no? Change the order of your if-else-if statements to make it so that one of the other responses is selected and try running it again.
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Activity 2.29.2.

What happens when a keyword is included in another word? Consider statements like “I know all the state capitals” which contains no and “I like vegetables smothered in cheese” which contains mother. Explain the problem with the responses to these statements.

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Subsection 2.29.2.2 Activity 2: Actual Code - (Optional)

You can do all of Activity 2 with the actual code using the Scanner class for input instead if you prefer.

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Here is the actual code for the Magpie lab on replit.com. It uses the Scanner class to read input from the user. The Scanner class is not on the AP CSA exam. You can log in to replit.com and use this code and change it to do this lab.

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Or you can copy and paste in the code from below into any Integrated Development Environment (IDE) like DrJava or JGrasp to run on your computer.

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Here is the code for MagpieRunner2.java.

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import java.util.Scanner;

/**
 * A simple class to run the Magpie class.
 *
 * @author Laurie White
 * @version April 2012
 */
public class MagpieRunner2
{

    /** Create a Magpie, give it user input, and print its replies. */
    public static void main(String[] args)
    {
        Magpie2 maggie = new Magpie2();

        System.out.println(maggie.getGreeting());
        Scanner in = new Scanner(System.in);
        String statement = in.nextLine();

        while (!statement.equals("Bye"))
        {
            System.out.println(maggie.getResponse(statement));
            statement = in.nextLine();
        }
    }
}

Here is the code for Magpie2.java.

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public class Magpie2
{
    /**
     * Get a default greeting
     *
     * @return a greeting
     */
    public String getGreeting()
    {
        return "Hello, let's talk.";
    }

    /**
     * Gives a response to a user statement
     *
     * @param statement the user statement
     * @return a response based on the rules given
     */
    public String getResponse(String statement)
    {
        String response = "";
        if (statement.indexOf("no") >= 0)
        {
            response = "Why so negative?";
        } else if (statement.indexOf("mother") >= 0
                || statement.indexOf("father") >= 0
                || statement.indexOf("sister") >= 0
                || statement.indexOf("brother") >= 0)
        {
            response = "Tell me more about your family.";
        }
        else
        {
            response = getRandomResponse();
        }
        return response;
    }

    /**
     * Pick a default response to use if nothing else fits.
     *
     * @return a non-committal string
     */
    private String getRandomResponse()
    {
        final int NUMBER_OF_RESPONSES = 4;
        double r = Math.random();
        int whichResponse = (int) (r * NUMBER_OF_RESPONSES);
        String response = "";

        if (whichResponse == 0)
        {
            response = "Interesting, tell me more.";
        }
        else if (whichResponse == 1)
        {
            response = "Hmmm.";
        }
        else if (whichResponse == 2)
        {
            response = "Do you really think so?";
        }
        else if (whichResponse == 3)
        {
            response = "You don't say.";
        }

        return response;
    }
}

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Section 2.29.3 Activity 3: Better Keyword Detection

This activity introduces you to some new String methods including some that are not on the exam, but are useful. Your teacher will tell you whether your class is doing this activity or not.

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Subsection 2.29.3.1 More String Methods

Run the StringExplorer below. It currently has code to illustrate the use of the indexOf and toLowerCase methods. Do they do what you thought they would? The method indexOf is on the exam and the method toLowerCase is not. Why do you think you might want to change the string to all lowercase characters? Why doesn’t the value of sample change?

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Activity 2.29.1.

Run the code below. Why do you think you might want to change the string to all lowercase characters? Why doesn’t the value of sample change? Do string methods change the string? Try some other string methods.

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/**
 * A program to allow students to try out different String methods.
 *
 * @author Laurie White
 * @version April 2012
 */
public class StringExplorer
{

public static void main(String[] args)
    {
        String sample = "The quick brown fox jumped over the lazy dog.";

//  Demonstrate the indexOf method.
        int position = sample.indexOf("quick");
        System.out.println("sample.indexOf(\"quick\") = " + position);

//  Demonstrate the toLowerCase method.
        String lowerCase = sample.toLowerCase();
        System.out.println("sample.toLowerCase() = " + lowerCase);
        System.out.println("After toLowerCase(), sample = " + sample);

//  Try other methods here:

}
}
====
// should pass if/when they run code
import static org.junit.Assert.*;

import org.junit.*;

import java.io.*;

public class RunestoneTests extends CodeTestHelper
{
    @Test
    public void testMain() throws IOException
    {
        String output = getMethodOutput("main");
        String expect = "sample.indexOf(\"quick\") = 4\n...";
        boolean passed = getResults(expect, output, "Expected output from main", true);
        assertTrue(passed);
    }
}

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Open the API for String in Java documentation| in another tab. Scroll down to the Method Summary section and find the indexOf(String str) method. Follow the link and read the description of the indexOf method.

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Activity 2.29.2.

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Copy the following lines to StringExplorer in the ActiveCode above in the main method above to see for yourself that indexOf behaves as specified:

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int notFoundPsn = sample.indexOf("slow");
System.out.println("sample.indexOf(\"slow\") = " + notFoundPsn);

Read the description of indexOf(String str, int fromIndex). Add lines to StringExplorer that illustrate how this version of indexOf differs from the one with one parameter.

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Subsection 2.29.3.2 Better Keyword Detection

In activity 2, you discovered that simply searching for collections of letters in a string does not always work as intended. For example, the word “cat” is in the string “Let’s play catch!”, but the string has nothing to do with the animal. In this activity, you will trace a method that searches for a full word in the string. It will check the substring before and after the string to ensure that the keyword is actually found.

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Take a look at the findKeyword method below. It has a while loop in it which we haven’t seen before. A while loop repeats the code in the block below it while a condition is true. A block is all the code inside of an open curly brace { and a close curly brace }.

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private int findKeyword(String statement, String goal,
        int startPos)
{
   String phrase = statement.trim();
   // The only change to incorporate the startPos is in
   // the line below
   int psn = phrase.toLowerCase().indexOf(goal.toLowerCase(),
                                          startPos);

   // Refinement--make sure the goal isn't part of a word
   while (psn >= 0)
   {
      // Find the string of length 1 before and after
      // the word
      String before = " ", after = " ";
      if (psn > 0)
      {
         before = phrase.substring(psn - 1, psn).toLowerCase();
      }
      if (psn + goal.length() < phrase.length())
      {
         after = phrase.substring(
                  psn + goal.length(),
                  psn + goal.length() + 1)
                  .toLowerCase();
      }

      /* determine the values of psn, before, and after at this point */

      // If before and after aren't letters, we've
      // found the word
      if (((before.compareTo("a") < 0) ||
           (before.compareTo("z") > 0)) // before is not a letter
          && ((after.compareTo("a") < 0) ||
              (after.compareTo("z") > 0)))
      {
          return psn;
      }

      // The last position didn't work, so let's find
      // the next, if there is one.
      psn = phrase.indexOf(goal.toLowerCase(),psn + 1);

   }

   return -1;
}

Run the code below or this JuiceMind IDE or this replit.com version 3 to see this new method findKeyword in action. It is called from the getResponse method to print out an appropriate response based on a keyword. For example, looking for the word "no" to print out "Why so negative?", but it won’t match no inside of another word like "another".

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if (findKeyword(statement, "no") >= 0)
{
   response = "Why so negative?";
}

You can also step through the code in the Java visualizer or using the CodeLens button below. It may take a minute or two to load. Click the forward button at the bottom of the code to execute the next statement.

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Activity 2.29.3.

Modify the code below to print the values of psn, before, and after right after the comment on line 100 in the findKeyword method below. Record each of the values in a table. The College Board student guide for the Magpie Chatbot Lab has a table on page 8 that can be printed. Use the CodeLens button to step through the code.

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/**
 * A program to carry on conversations with a human user. This version:
 *
 * 
 * Uses advanced search for keywords
 * 
 *
 * @author Laurie White
 * @version April 2012
 */
public class Magpie3
{
    /**
     * Get a default greeting
     *
     * @return a greeting
     */
    public String getGreeting()
    {
        return "Hello, let's talk.";
    }

/**
     * Gives a response to a user statement
     *
     * @param statement the user statement
     * @return a response based on the rules given
     */
    public String getResponse(String statement)
    {
        String response = "";
        if (statement.length() == 0)
        {
            response = "Say something, please.";
        }
        else if (findKeyword(statement, "no") >= 0)
        {
            response = "Why so negative?";
        } else if (findKeyword(statement, "mother") >= 0
                || findKeyword(statement, "father") >= 0
                || findKeyword(statement, "sister") >= 0
                || findKeyword(statement, "brother") >= 0)
        {
            response = "Tell me more about your family.";
        }
        else
        {
            response = getRandomResponse();
        }
        return response;
    }

/**
     * Search for one word in phrase. The search is not case sensitive. This method
     * will check that the given goal is not a substring of a longer string (so,
     * for example, "I know" does not contain "no").
     *
     * @param statement the string to search
     * @param goal the string to search for
     * @param startPos the character of the string to begin the search at
     * @return the index of the first occurrence of goal in statement or -1 if it's
     *     not found
     */
    private int findKeyword(String statement, String goal, int startPos)
    {
        String phrase = statement.trim();
        // The only change to incorporate the startPos is in
        // the line below
        int psn = phrase.toLowerCase().indexOf(goal.toLowerCase(), startPos);

// Refinement--make sure the goal isn't part of a
        // word
        while (psn >= 0)
        {
            // Find the string of length 1 before and after
            // the word
            String before = " ", after = " ";
            if (psn > 0)
            {
                before = phrase.substring(psn - 1, psn).toLowerCase();
            }
            if (psn + goal.length() < phrase.length())
            {
                after =
                        phrase.substring(
                                        psn + goal.length(),
                                        psn + goal.length() + 1)
                                .toLowerCase();
            }

/* determine the values of psn, before, and after at this point */

// If before and after aren't letters, we've
            // found the word
            if (((before.compareTo("a") < 0)
                            || (before.compareTo("z") > 0)) // before is not a
                    // letter
                    && ((after.compareTo("a") < 0)
                            || (after.compareTo("z") > 0)))
            {
                return psn;
            }

// The last position didn't work, so let's find
            // the next, if there is one.
            psn = phrase.indexOf(goal.toLowerCase(), psn + 1);
        }

return -1;
    }

/**
     * Search for one word in phrase. The search is not case sensitive. This method
     * will check that the given goal is not a substring of a longer string (so,
     * for example, "I know" does not contain "no"). The search begins at the
     * beginning of the string.
     *
     * @param statement the string to search
     * @param goal the string to search for
     * @return the index of the first occurrence of goal in statement or -1 if it's
     *     not found
     */
    private int findKeyword(String statement, String goal)
    {
        return findKeyword(statement, goal, 0);
    }

/**
     * Pick a default response to use if nothing else fits.
     *
     * @return a non-committal string
     */
    private String getRandomResponse()
    {
        final int NUMBER_OF_RESPONSES = 4;
        double r = Math.random();
        int whichResponse = (int) (r * NUMBER_OF_RESPONSES);
        String response = "";

return response;
    }

public static void main(String[] args)
    {
        Magpie3 maggie = new Magpie3();

maggie.findKeyword("yesterday is today's day before.", "day", 0);
    }
}
====
// should pass if/when they run code
import static org.junit.Assert.*;

import org.junit.*;

import java.io.*;

public class RunestoneTests extends CodeTestHelper
{
    @Test
    public void testMain() throws IOException
    {
        String output = getMethodOutput("main");
        String expect = "6...";
        boolean passed = getResults(expect, output, "Expected output from main", true);
        assertTrue(passed);
    }
}

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Subsection 2.29.3.3 Exercise: Use the new method

Repeat the changes you made to the program in Activity 2, using this new method to detect keywords. You can use the active code window above, or the JuiceMind IDE or the replit.com version 3 or your own IDE.

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Subsection 2.29.3.4 Questions: Prepare for the next activity

Single keywords are interesting, but better chatbots look for groups of words. Consider statements like “I like cats,” “I like math class,” and “I like Spain.” All of these have the form “I like something.” The response could be “What do you like about something?” The next activity will expand on these groups. You will get to add one of your own, so it’s a good idea to start paying close attention to common phrases in your own conversations.

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Section 2.29.4 Activity 4: Responses that Transform Statements

If your class has time, your teacher may have you do Activity 4 below.

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As stated previously, single keywords are interesting, but better chatbots look for groups of words. Statements like “I like cats”, “I like math class”, and “I like Spain” all have the form “I like something”. The response could be “What do you like about something?” This activity will respond to groupings of words.

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Try each of the following as the value for the statement in the main method and see what they print. Or you can try it on JuiceMind IDE or on replit.com version 4.

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I want to understand French.
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Do you like me?
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You confuse me.
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You can also step through the code in the Java visualizer. It may take a minute or two to load. Click the forward button at the bottom of the code to execute the next statement.

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Activity 2.29.1.

Try Mapgpie4 below.

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/**
 * A program to carry on conversations with a human user. This version:
 *
 * 
 *   Uses advanced search for keywords
 *   Will transform statements as well as react to keywords
 * 
 *
 * @author Laurie White
 * @version April 2012
 */
public class Magpie4
{

/**
     * Get a default greeting
     *
     * @return a greeting
     */
    public String getGreeting()
    {
        return "Hello, let's talk.";
    }

// Responses which require transformations
        else if (findKeyword(statement, "I want to", 0) >= 0)
        {
            response = transformIWantToStatement(statement);
        }

// ADD Responses which require transformations!

else
        {
            // Look for a two word (you <something> me)
            // pattern
            int psn = findKeyword(statement, "you", 0);

if (psn >= 0 && findKeyword(statement, "me", psn) >= 0)
            {
                response = transformYouMeStatement(statement);
            }
            else
            {
                response = getRandomResponse();
            }
        }
        return response;
    }

/**
     * Take a statement with "I want to <something>." and transform it into "What
     * would it mean to <something>?"
     *
     * @param statement the user statement, assumed to contain "I want to"
     * @return the transformed statement
     */
    private String transformIWantToStatement(String statement)
    {
        //  Remove the final period, if there is one
        statement = statement.trim();
        String lastChar = statement.substring(statement.length() - 1);
        if (lastChar.equals("."))
        {
            statement = statement.substring(0, statement.length() - 1);
        }
        int psn = findKeyword(statement, "I want to", 0);
        String restOfStatement = statement.substring(psn + 9).trim();
        return "What would it mean to " + restOfStatement + "?";
    }

/**
     * ADD CODE HERE! Take a statement with "I want <something>." and transform it
     * into Would you really be happy if you had <something>?
     *
     * @param statement the user statement, assumed to contain "I want"
     * @return the transformed statement
     */
    private String transformIWantStatement(String statement)
    {
        // ADD CODE HERE

return "Would you really be happy if you had ...";
    }

/**
     * Take a statement with "you <something> me" and transform it into "What makes
     * you think that I <something> you?"
     *
     * @param statement the user statement, assumed to contain "you" followed by
     *     "me"
     * @return the transformed statement
     */
    private String transformYouMeStatement(String statement)
    {
        //  Remove the final period, if there is one
        statement = statement.trim();
        String lastChar = statement.substring(statement.length() - 1);
        if (lastChar.equals("."))
        {
            statement = statement.substring(0, statement.length() - 1);
        }

int psnOfYou = findKeyword(statement, "you", 0);
        int psnOfMe = findKeyword(statement, "me", psnOfYou + 3);

String restOfStatement = statement.substring(psnOfYou + 3, psnOfMe).trim();
        return "What makes you think that I " + restOfStatement + " you?";
    }

/**
     * ADD THIS Take a statement with "I <something> you" and transform it into
     * "Why do you <something> me?"
     *
     * @param statement the user statement, assumed to contain "I" followed by
     *     something "you"
     * @return the transformed statement
     */
    private String transformIMeStatement(String statement)
    {
        // ADD CODE HERE
        return "Why do you...";
    }

/**
     * Search for one word in phrase. The search is not case sensitive. This method
     * will check that the given goal is not a substring of a longer string (so,
     * for example, "I know" does not contain "no").
     *
     * @param statement the string to search
     * @param goal the string to search for
     * @param startPos the character of the string to begin the search at
     * @return the index of the first occurrence of goal in statement or -1 if it's
     *     not found
     */
    private int findKeyword(String statement, String goal, int startPos)
    {
        String phrase = statement.trim();
        //  The only change to incorporate the startPos is in the line below
        int psn = phrase.toLowerCase().indexOf(goal.toLowerCase(), startPos);

//  Refinement--make sure the goal isn't part of a word
        while (psn >= 0)
        {
            //  Find the string of length 1 before and after the word
            String before = " ", after = " ";
            if (psn > 0)
            {
                before = phrase.substring(psn - 1, psn).toLowerCase();
            }
            if (psn + goal.length() < phrase.length())
            {
                after =
                        phrase.substring(
                                        psn + goal.length(),
                                        psn + goal.length() + 1)
                                .toLowerCase();
            }

//  If before and after aren't letters, we've found the word
            if (((before.compareTo("a") < 0)
                            || (before.compareTo("z")
                                    > 0)) //  before is not a letter
                    && ((after.compareTo("a") < 0)
                            || (after.compareTo("z") > 0)))
                            {
                return psn;
            }

//  The last position didn't work, so let's find the next, if there is
            // one.
            psn = phrase.indexOf(goal.toLowerCase(), psn + 1);
        }

return -1;
    }

/**
     * Search for one word in phrase. The search is not case sensitive. This method
     * will check that the given goal is not a substring of a longer string (so,
     * for example, "I know" does not contain "no"). The search begins at the
     * beginning of the string.
     *
     * @param statement the string to search
     * @param goal the string to search for
     * @return the index of the first occurrence of goal in statement or -1 if it's
     *     not found
     */
    private int findKeyword(String statement, String goal)
    {
        return findKeyword(statement, goal, 0);
    }

return response;
    }

public static void main(String[] args)
    {
        Magpie4 maggie = new Magpie4();
        String statement = "I want to build a robot.";
        System.out.println("Statement: " + statement);
        System.out.println("Response: " + maggie.getResponse(statement));
    }
}

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Subsection 2.29.4.1 Exercises:

In this activity, the chatbot is altered to look not only for keywords, but also specific phrases. Magpie4.java adds two new methods, transformIWantToStatement and transformYouMeStatement and getResponse has been modified to add tests to find “I want to something” statements and “You something me” statements.

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Look at the code. See how it handles “I want to” and you/me statements.

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Then add two new methods, transformIWantStatement and transformIYouStatement, and calls to each as described below. Alter the code either above in the active code window or on JuiceMind IDE or on replit.com version 4 or in an IDE of your choice:

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In a method transformIWantStatement, have it respond to “I want something” statements with “Would you really be happy if you had something?” You can use the already written transformIWantToStatement method as a guide. In doing this, you need to be careful about where you place the call to the method so it calls the right one. Test with the following:
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- Statement: I want fried chicken.
  🔗
  
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- Response: Would you really be happy if you had fried chicken?
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🔗
In a method transformIYouStatement, have it respond to statements of the form “I something you” with the restructuring “Why do you something me?”. You can use the transformYouMeStatement method as a guide. Test with the following:
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- Statement: I like you.
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- Response: Why do you like me?
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Find an example of when this structure does not work well. How can you improve it?

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Section 2.29.5 Mixed Up Code Practice

Activity 2.29.1.

The following program segment should print 4 random responses using if/else statements, but the blocks have been mixed up. Drag the blocks from the left and put them in the correct order on the right. Click the Check button to check your solution.

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private String getRandomResponse()
{
---
    final int NUMBER_OF_RESPONSES = 4;
    double r = Math.random();
---
    int whichResponse = (int)(r * NUMBER_OF_RESPONSES);
    String response = "";
---
    if (whichResponse == 0)
    {
        response = "Interesting, tell me more.";
---
    }
    else if (whichResponse == 1)
    {
        response = "Hmmm.";
---
    }
    else if (whichResponse == 2)
    {
        response = "Do you really think so?";
---
    }
    else if (whichResponse == 3)
    {
        response = "You don't say.";
    }
---
    return response;
---
}

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You have attempted of activities on this page.

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