Struts 2 Actions
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Transcript Struts 2 Actions
Struts 2 Actions
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By,
Srinivas Reddy.S
Agenda
•
•
•
•
•
Action and its role
Packages and namespaces
Results
Action and ActionSupport
Using wildcards
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A Simple Birthday Action
URL: http://localhost:8080/struts2actions/greetings/birthday
When accessed, a page asking for the persons name should be displayed
URL: http://localhost:8080/struts2actions/greetings/happybirthday
This displays the success page which greets the person.
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A Simple Birthday Action
Step 1: Create a JSP:
birthday.jsp
<%@ page contentType="text/html; charset=UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<body>
<h1>Enter the Birthday Boys name:</h1>
<s:form action ="happybirthday">
<s:textfield name="birthdayBoy" label="Birthday Boy
Name:"/>
<s:submit/>
</s:form>
</body>
</html>
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A Simple Birthday Action
Step 2: Create an Action class to handle the form
HappyBirthday.java
package greetings;
public class HappyBirthday {
private String birthdayBoy;
public String execute(){
if(this.getBirthdayBoy().equals(“”)||this.getBirthdayBoy()==null){
return “failure";
}else{
return “SUCCESS";
}
}
public String getBirthdayBoy() {
return birthdayBoy;
}
public void setBirthdayBoy(String birthdayBoy) {
this.birthdayBoy = birthdayBoy;
}
}
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A Simple Birthday Action
Step 3: Create the Success and failure JSPs
birthdaySuccess.jsp
<%@ page contentType="text/html; charset=UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<body>
<h1>Wish you a Very Happy Birthday to You :-) <s:property value="birthdayBoy"/></h1>
</body>
</html>
noBirthday.jsp
<%@ page contentType="text/html; charset=UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<body>
<h1>LOOKS LIKE NO BODY IS CELEBRATING BIRTHDAY TODAY</h1>
</body>
</html>
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A Simple Birthday Action
Step 4: Configure the Struts.xml
<package name="default" namespace="/greetings" extends="struts-default">
<action name ="birthday" >
<result>/pages/birthday.jsp</result>
</action>
<action name ="happybirthday" class ="greetings.HappyBirthday">
<result name ="SUCCESS">/pages/birthdaySuccess.jsp</result>
<result name ="failure">/pages/noBirthday.jsp</result>
</action>
</package>
Note: Struts.xml should be in WEB-INF/classes folder
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Role of Action
• Controller
• Data carrier
• Result to be invoked
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Action as Controller
public String execute(){
if(this.getBirthdayBoy().equals(“”)||this.getBirthdayBoy()==null){
return “failure";
}else{
BirthdayUtil.calculateAge(birthDate); Other business layer or service layer
return “SUCCESS";
}
}
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Action as Data Carrier
public class HappyBirthday { A simple POJO
private String birthdayBoy;
public String getBirthdayBoy() {
return birthdayBoy;
}
public void setBirthdayBoy(String birthdayBoy) {
this.birthdayBoy = birthdayBoy;
}
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Action as Result render
public String execute(){
if(this.getBirthdayBoy().equals(“”)||this.getBirthdayBoy()==null){
return “failure";
}else{
return “SUCCESS";
}
}
<action name ="happybirthday" class ="greetings.HappyBirthday">
<result name ="SUCCESS">/pages/birthdaySuccess.jsp</result>
<result name ="failure">/pages/noBirthday.jsp</result>
</action>
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No execute() method
• You can specify a different method other
than execute method to play as controller
method.
<action name ="happybirthday" class ="greetings.HappyBirthday“
method =“wishForBirthday”>
<result name ="SUCCESS">/pages/birthdaySuccess.jsp</result>
<result name ="failure">/pages/noBirthday.jsp</result>
</action>
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Packages and Namespaces
<package name=“
greetings" namespace="/greetings" extends="struts-default">
<action name ="birthday" >
<result>/pages/birthday.jsp</result>
</action>
<action name ="happybirthday" class ="greetings.HappyBirthday">
<result name ="SUCCESS">/pages/birthdaySuccess.jsp</result>
<result name ="failure">/pages/noBirthday.jsp</result>
</action>
</package>
/reminder" extends="struts-
<package name=“reminders" namespace="
default">
<action name=“myreminder” …/>
</package>
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Packages and Namespaces
• Note:
– Package name is mandatory.
– namespace is optional but the default is “/”.
– extends – to extend a parent package.
• abstract- If true, this package will only be used to
define inheritable components, not actions
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Result and types
•
•
•
•
•
•
JSP
Velocity
Freemarker
Xslt
Text
Stream
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Result and types
<action name ="happybirthday" class ="greetings.HappyBirthday">
<result name ="SUCCESS">/pages/birthdaySuccess.jsp</result>
<result name ="failure">/pages/noBirthday.jsp</result>
</action>
Attributes:
name – should match with the return string from the execute method.
Default is “SUCCESS”
type – chain, dispatcher, freemarker, httpheader, redirect, redirectAction,
stream, velocity, xslt, plaintext, tiles
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Action Interface
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ActionSupport class
• Implements the interfaces Action, LocaleProvider,
TextProvider, Validateable, ValidationAware,
Serializable
• Supports Internationalization.
• Supports Programmatic validation.
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ModelDriven Interface
• Used to tell that the form details to be filled
to a different POJO instead of Action class
itself.
• Eg., public class Login implements ModelDriven{
private User user = new User();
public Object getModel(){
return user;
}
}
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Using Wildcards
<action name="*">
<result>/WEB-INF/jsps/{1}.jsp</result>
</action>
URL:
http://localhost:8080/struts2actions/testwildcard
/WEB-INF/jsps/testwildcard.jsp
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Using Wildcards
<action name="*/*">
<result>/WEB-INF/jsps/{1}/{2}.jsp</result>
</action>
URL:
http://localhost:8080/struts2action/test/testwildcard
/WEB-INF/jsps/test/testwildcard.jsp
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External configuration files
Struts.xml
</package>
<include file="com/java9s/struts2/actions/shopping.xml"/>
</struts>
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Thank you
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example code from
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