(Phone Book Application: Functionality) Define the middle tier for the Phone Book application.

a) Opening phoneBook.jsp. Open the phoneBook.jsp file that you modified.
b) Defining the form’s method and action attributes in the phoneBook.jsp page. In the phoneBook.jsp source code, specify "post" as the form element’s method and use the action attribute to forward the client request to phoneNumber.jsp.
c) Populating the HTML menu control with names. In the phoneBook.jsp source code, add a while statement to the scriptlet in phoneBook.jsp. The loop should add each person’s name (retrieved from the ResultSet) to the HTML menu control. This step requires literal HTML markup and a JSP expression as well.
d) Closing the ResultSet. In the scriptlet that ends the while statement, add code to close the ResultSet by invoking its close method.
e) Saving the file. Save your modified source code file.
f) Opening phoneNumber.jsp. Open the phoneNumber.jsp file that you modified in
Exercise 31.11.
g) Displaying the selected name. In the phoneNumber.jsp source code, modify the h1 header element to display the selected name that is received as part of the client request.
h) Displaying the phone number. In the phoneNumber.jsp source code, modify the HTML paragraph element that contains “numbers” to display the phone number that corresponds to the selected name. Note that you need to move the cursor to the first row of the ResultSet to retrieve the phone number.
i) Closing the ResultSet. In the scriptlet that appears after the code you added in
Step h, add code to close the ResultSet by invoking its close method.
j) Saving the file. Save your modified source code file.
k) Copying phoneBook.jsp and phoneNumber.jsp to the PhoneBook directory. Copy your updated phoneBook.jsp and phoneNumber.jsp files and paste them into the C:\Program Files\Apache Group\Tomcat 4.1\webapps\PhoneBook directory.
l) Starting Tomcat. Select Start > Programs > Apache Tomcat 4.1 > Start Tomcat to start the Tomcat server.
m)Testing the application. Open a Web browser and enter the URL http:// localhost:8080/PhoneBook/phoneBook.jsp, select a name from the list and click the Get Number button to test the application.
n) Stopping Tomcat. Select Start > Programs > Apache Tomcat 4.1 > Stop Tomcat to stop the Tomcat server.

```
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4 <%-- import java.sql.* for database classes --%>
5 <%@ page import = "java.sql.*" %>
6
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12 Phone Book
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17

Phone Book Web Application

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Select a name from the list and click
23 the Get Number button

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```

```
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4 <%-- import java.sql.* for database classes --%>
5 <%@ page import = "java.sql.*" %>
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12 Phone Number
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<%= request.getParameter( "personName" ) %>

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19 <%-- begin JSP scriptlet to connect to a database --%>
20 <%
21 // setup database connection
22 try
23 {
24 // specify database location
25 System.setProperty( "db2j.system.home",
26 "C:\\Examples\\Tutorial31\\Exercises\\Databases" );
27
28 // load Cloudscape driver
29 Class.forName( "com.ibm.db2j.jdbc.DB2jDriver" );
30
31 // connect to database
32 Connection connection = DriverManager.getConnection(
33 "jdbc:db2j:phonebook" );
34
35 // obtain information from database
36 if ( connection != null )
37 {
38 // create statement
39 Statement statement = connection.createStatement();
40
41 // execute query to get all information
42 ResultSet results = statement.executeQuery(
43 "SELECT * FROM phoneNumbers WHERE name = '" +
44 request.getParameter( "personName" ) + "'" );
45
46 results.next(); // move cursor to the first row
47
48 %> <%-- end scriptlet to insert HTML --%>
49
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<%= results.getString( "phoneNumber" ) %>

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53

Phone Book

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55 <% // continue scriptlet
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57 results.close(); // close result set
58 connection.close(); // close database connection
59
60 } // end if
61
62 } // end try
63
64 // catch SQLException
65 catch( SQLException exception )
66 {
67 out.println( "Exception: " + exception + " occurred." );
68 }
69
70 %> <%-- end scriptlet --%>
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```