Introduction to Struts 2.0
Jenny Ni
Joey Feng
Winddays Wang
Hewmmi Zhu
Heather Lv
1
Software School ,Fudan University
Contents
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 2.0
10. What you need to start using Struts2.0
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What is Struts?
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
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Why use framework?
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.
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Struts 2.0
Complete new framework based on webwork framework.
Struts 2.0 implements MVC 2 design pattern.
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Struts 2.0 MVC Components
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.
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Struts 2.0 MVC Components contd.
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
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Request Lifecycle in Struts 2.0
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.
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Struts 2.0 Architecture
Struts 2.0 Architecture
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Why we should use Struts 2.0?
1. Simplified Design
2. Simplified Action
3. Simplified Testability
4. Better tag features
5. Annotation introduced
6. Easy plug-in
7. AJAX Support
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Struts 1.x vs Struts 2.0
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
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Struts 1 Struts 2
Action Action
ActionForm Action or POJO’s
ActionForward Result
struts-config.xml struts.xml
ActionServlet FilterDispatcher
RequestProcessor Interceptors
What you need to start using
Struts 2.0?
1. Java 5.0
2. Tomcat 5.x(Servlet api 2.4 and jsp api
2.0)
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Let’s see something real…
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Web, Mail 2000
Web, Mail 2009
Struts Plugins
Simple Example
Struts 1
Name:
Date:
Invitees:
Description:
Save
...
Only four pages!
Struts 2
Example Revisited
...
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
Run Struts 1 Actions as Is
com.mycompany.gangstas.EditGangsterAction
gangsterForm.jsp
How do I get
started?
Where We are Going