Introduction to Struts 2.0 Jenny Ni Joey Feng Winddays Wang Hewmmi Zhu Heather Lv Software School,Fudan University 1

1. What is Struts? 2. Why to use framework? 3. Struts 2.0 Overview 4. Struts 2.0 MVC components 5. Request Lifecycle in Struts 2 6. Struts 2.0 Architecture 7. Sample Application 8. Why we should use Struts 2.0? 9. Struts 1.x vs Struts What you need to start using Struts2.0 Contents Software School,Fudan University 2

 Open Source java framework for creating web applications.  Action Based Framework  Create web application using MVC 2 architecture  Apache Struts offer two major version  Struts 1.x  Struts 2.0  Struts 2 = WebWork + Struts What is Struts? Software School,Fudan University 3

 Do we need framework?  No and Yes.  No.  In small applications where you don’t want the overhead of learning new things.  But  Yes  We have to use framework in real world application because:-  Automation of common tasks  Concentrate on higher level concerns. Why use framework? Software School,Fudan University 4

 Complete new framework based on webwork framework.  Struts 2.0 implements MVC 2 design pattern. Struts 2.0 Software School,Fudan University 5

 Controller:-  Filter Dispatcher:-  First component that start processing that is why this type of MVC is called front controller MVC  Looks at the request and apply the appropriate action.  Struts framework handles all of the controller work.  Its configured in web.xml  Interceptors:-  Can execute code before and after an Action is executed.  They can be configured per action basis.  Can be used for data validation, file upload, double submit guards. Struts 2.0 MVC Components Software School,Fudan University 6

 Model:-  Implemented by action class  For model you can use any data access technologies like JDBC,EJB,Hibernate  View  Its your result part. It can be JSP,JSTL,JSF etc.  Presentation part of the MVC Struts 2.0 MVC Components contd. Software School,Fudan University 7

1. User Sends Request 2. Filter Dispatcher determines the appropriate action 3. Interceptors are applied 4. Execution of action 5. Output Rendering 6. Return of Request 7. Display of result to user. Request Lifecycle in Struts 2.0 Software School,Fudan University 8

Struts 2.0 Architecture

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1. Simplified Design 2. Simplified Action 3. Simplified Testability 4. Better tag features 5. Annotation introduced 6. Easy plug-in 7. AJAX Support Why we should use Struts 2.0? Software School,Fudan University 11

 How Struts 1.x and Struts 2.0 differ from each other? › Configuration › Action Class › Dependency injection. › Servlet Dependency › Validation › Threading model › Testability › Expression Language Struts 1.x vs Struts 2.0 Software School,Fudan University 12

Struts 1 Action  ActionForm  ActionForward  struts-config.xml  ActionServlet  RequestProcessor  Struts 2 Action Action or POJO’s Result struts.xml FilterDispatcher Interceptors

1. Java Tomcat 5.x(Servlet api 2.4 and jsp api 2.0) What you need to start using Struts 2.0? Software School,Fudan University 14

Let’s see something real… Software School,Fudan University 15

Web, Mail 2000

Web, Mail 2009

Struts Plugins

Simple Example

Name: Date: Struts 1

Invitees: <html:select property="invitees" multiple="true"> <html:options collection="employees" property="value" labelProperty="label"/>

Description: <html:textarea property="description" rows="4" cols="50" />

...  Only four pages! Save

<s:textarea label=”Description” name="description" rows="4" cols="50" /> Struts 2

Example Revisited

<s:textfield label="Name" name="name" tooltip="Meeting name" />

<jsp:include page="/ajax/commonInclude.jsp"/>... <s:textarea theme="ajax" label="Description" name="description" rows="4" cols="50" />

But there's more...

Brian Kernighan Law of Debugging Difficulty Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it.

Prevention and Cure

struts.devMode = true

Built-in Testing Support public class MyActionTest extends StrutsTestCase { public void testExecute() throws Exception { assertTrue(true); }

any.action?debug=console

any.action?profiling=yes

Time to Upgrade?

Tutorials, Guides, and FAQs

Struts 2 Training Course

<action name="editGangster" class="org.apache.struts2.s1.Struts1Action"> com.mycompany.gangstas.EditGangsterAction gangsterForm.jsp Run Struts 1 Actions as Is

How do I get started?

Where We are Going