This document provides steps to build a simple Struts application, including creating forms, actions, configuration files, and JSP pages. The key steps are: 1. Set up the project directory structure and files like web.xml. 2. Define forms, actions, and mappings in struts-config.xml. 3. Create ActionForm classes to handle form fields and validation. 4. Write Action classes to process requests and select views. 5. Develop JSP pages to display forms and output using Struts tags. 6. Build, deploy and test the complete application.

1. Step by Step Guide
for building a simple
Struts Application
1

2. Sang Shin
sang.shin@sun.com
www.javapassion.com/j2ee
Java™ Technology Evangelist
Sun Microsystems, Inc.
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3. Sample App We are
going to build
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4. Sample App
● Keld Hansen's submit application
● Things to do
– Creating ActionForm object
– Creating Action object
– Forwarding at either success or failure through
configuration set in struts-config.xml file
– Input validation
– Internationalizaition
● You can also build it using NetBeans
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5. Steps to follow
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6. Steps
1.Create development directory structure
2.Write web.xml
3.Write struts-config.xml
4.Write ActionForm classes
5.Write Action classes
6.Create ApplicationResource.properties
7.Write JSP pages
8.Build, deploy, and test the application
6

7. Step 1: Create Development
Directory Structure
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8. Development Directory
Structure
● Same development directory structure for
any typical Web application
● Ant build script should be written
accordingly
● If you are using NetBeans, the
development directory structure is
automatically created
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9. Step 2: Write web.xml
Deployment Descriptor
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10. web.xml
● Same structure as any other Web
application
– ActionServlet is like any other servlet
– Servlet definition and mapping of ActionServlet
needs to be specified in the web.xml
● There are several Struts specific
<init-param> elements
– Location of Struts configuration file
● Struts tag libraries could be defined
10

11. Example: web.xml
1 <?xml version="1.0" encoding="UTF-8"?>
2 <web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
3 <servlet>
4 <servlet-name>action</servlet-name>
5 <servlet-class>org.apache.struts.action.ActionServlet</servlet-class>
6 <init-param>
7 <param-name>config</param-name>
8 <param-value>/WEB-INF/struts-config.xml</param-value>
9 </init-param>
10 ...
11 </servlet>
12 <servlet-mapping>
13 <servlet-name>action</servlet-name>
14 <url-pattern>*.do</url-pattern>
15 </servlet-mapping>
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12. Step 3: Write
struts-config.xml
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13. struts-config.xml
● Identify required input forms and then define
them as <form-bean> elements
● Identify required Action's and then define them
as <action> elements within <action-mappings>
element
– make sure same value of name attribute of <form-
bean> is used as the value of name attribute of
<action> element
– define if you want input validation
● Decide view selection logic and specify them as
<forward> element within <action> element
13

14. struts-config.xml: <form-beans>
1 <?xml version="1.0" encoding="UTF-8" ?>
2
3 <!DOCTYPE struts-config PUBLIC
4 "-//Apache Software Foundation//DTD Struts Configuration 1.2//EN"
5 "http://jakarta.apache.org/struts/dtds/struts-config_1_2.dtd">
6
7
8 <struts-config>
9 <form-beans>
10 <form-bean name="submitForm"
11 type="submit.SubmitForm"/>
12 </form-beans>
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15. struts-config.xml:
<action-mappings>
1
2 <!-- ==== Action Mapping Definitions ===============-->
3 <action-mappings>
4
5 <action path="/submit"
6 type="submit.SubmitAction"
7 name="submitForm"
8 input="/submit.jsp"
9 scope="request"
10 validate="true">
11 <forward name="success" path="/submit.jsp"/>
12 <forward name="failure" path="/submit.jsp"/>
13 </action>
14
15 </action-mappings>
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16. Step 4: Write
ActionForm classes
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17. ActionForm Class
● Extend org.apache.struts.action.ActionForm
class
● Decide set of properties that reflect the input
form
● Write getter and setter methods for each
property
● Write validate() method if input validation is
desired
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18. Write ActionForm class
1 package submit;
2
3 import javax.servlet.http.HttpServletRequest;
4 import org.apache.struts.action.*;
5
6 public final class SubmitForm extends ActionForm {
7
8 /* Last Name */
9 private String lastName = "Hansen"; // default value
10 public String getLastName() {
11 return (this.lastName);
12 }
13 public void setLastName(String lastName) {
14 this.lastName = lastName;
15 }
16
17 /* Address */
18 private String address = null;
19 public String getAddress() {
20 return (this.address);
21 }
22 public void setAddress(String address) {
23 this.address = address;
24 } 18

19. Write validate() method
1 public final class SubmitForm extends ActionForm {
2
3 ...
4 public ActionErrors validate(ActionMapping mapping,
5 HttpServletRequest request) {
6
7 ...
8
9 // Check for mandatory data
10 ActionErrors errors = new ActionErrors();
11 if (lastName == null || lastName.equals("")) {
12 errors.add("Last Name", new ActionError("error.lastName"));
13 }
14 if (address == null || address.equals("")) {
15 errors.add("Address", new ActionError("error.address"));
16 }
17 if (sex == null || sex.equals("")) {
18 errors.add("Sex", new ActionError("error.sex"));
19 }
20 if (age == null || age.equals("")) {
21 errors.add("Age", new ActionError("error.age"));
22 }
23 return errors;
24 } 19

20. Step 5: Write
Action classes
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21. Action Classes
● Extend org.apache.struts.action.Action class
● Handle the request
– Decide what kind of server-side Model objects
(EJB, JDO, etc.) can be invoked
● Based on the outcome, select the next view
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22. Example: Action Class
1 package submit;
2
3 import javax.servlet.http.*;
4 import org.apache.struts.action.*;
5
6 public final class SubmitAction extends Action {
7
8 public ActionForward execute(ActionMapping mapping,
9 ActionForm form,
10 HttpServletRequest request,
11 HttpServletResponse response) {
12
13 SubmitForm f = (SubmitForm) form; // get the form bean
14 // and take the last name value
15 String lastName = f.getLastName();
16 // Translate the name to upper case
17 //and save it in the request object
18 request.setAttribute("lastName", lastName.toUpperCase());
19
20 // Forward control to the specified success target
21 return (mapping.findForward("success"));
22 }
23 } 22

23. Step 6: Create
ApplicationResource.properties
and Configure web.xml
accordingly
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24. Resource file
● Create resource file for default locale
● Create resource files for other locales
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25. Example:
ApplicationResource.properties
1 errors.header=<h4>Validation Error(s)</h4><ul>
2 errors.footer=</ul><hr>
3
4 error.lastName=<li>Enter your last name
5 error.address=<li>Enter your address
6 error.sex=<li>Enter your sex
7 error.age=<li>Enter your age
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26. Step 7: Write JSP pages
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27. JSP Pages
● Write one JSP page for each view
● Use Struts tags for
– Handing HTML input forms
– Writing out messages
27

28. Example: submit.jsp
1 <%@ page language="java" %>
2 <%@ taglib uri="/WEB-INF/struts-bean.tld" prefix="bean" %>
3 <%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>
4 <%@ taglib uri="/WEB-INF/struts-logic.tld" prefix="logic" %>
5
6 <html>
7 <head><title>Submit example</title></head>
8 <body>
9
10 <h3>Example Submit Page</h3>
11
12 <html:errors/>
13
14 <html:form action="submit.do">
15 Last Name: <html:text property="lastName"/><br>
16 Address: <html:textarea property="address"/><br>
17 Sex: <html:radio property="sex" value="M"/>Male
18 <html:radio property="sex" value="F"/>Female<br>
19 Married: <html:checkbox property="married"/><br>
20 Age: <html:select property="age">
21 <html:option value="a">0-19</html:option>
22 <html:option value="b">20-49</html:option>
23 <html:option value="c">50-</html:option>
24 </html:select><br>
25 <html:submit/>
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26 </html:form>

29. Example: submit.jsp
1 <logic:present name="lastName" scope="request">
2 Hello
3 <logic:equal name="submitForm" property="age" value="a">
4 young
5 </logic:equal>
6 <logic:equal name="submitForm" property="age" value="c">
7 old
8 </logic:equal>
9 <bean:write name="lastName" scope="request"/>
10 </logic:present>
11
12 </body>
13 </html>
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30. Step 8: Build, Deploy,
and Test Application
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31. Accessing Web Application
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32. Accessing Web Application
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33. Accessing Web Application
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34. Passion!
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