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This tutorial assumes you've completed the Hello World tutorial and have a working helloworld project. The example code for this tutorial, using_tags, is available for checkout from the Struts 2 subversion sandbox at https://svn.apache.org/repos/asf/struts/sandbox/trunk/struts2examples^{Image Removed}. The example projects use Maven to manage the artifact dependencies and to build the .war files.

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Examine the struts.xml configuration in the Hello World tutorial and you will find this:

xml

Code Block

	xml
title	struts.xml
borderStyle	solid
	xml

...
<action name="hello" class="org.apache.struts.helloworld.action.HelloWorldAction" method="execute">
  <result name="success">/HelloWorld.jsp</result>
</action>
...

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For the Using Tags tutorial add the following to index.jsp just after the link for Hello World.

Code Block

	html	html
title	url tag with param
	html


<s:url action="hello" var="helloLink">
  <s:param name="userName">Bruce Phillips</s:param>
</s:url>

<p><a href="${helloLink}">Hello Bruce Phillips</a></p>

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Add the following markup to index.jsp after the Hello Bruce Phillips link.

Code Block

	html	html
title	Struts 2 Form
	html


<p>Get your own personal hello by filling out and submitting this form.</p>

<s:form action="hello">

  <s:textfield name="userName" label="Your name" />
	
   <s:submit value="Submit" />

</s:form>

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The Struts form, textfield, and submit tags were converted to this HTML.

Code Block

	html	html
title	Struts Form Tags Converted To HTML
	html

<form id="hello" name="hello" action="/Using_Tags_Struts2_Mvn/hello.action;jsessionid=3471d76027b5342cab44f297b567" method="post">

<table class="wwFormTable">

<tr>
    <td class="tdLabel"><label for="hello_userName" class="label">Your name:</label></td>
    <td><input type="text" name="userName" value="" id="hello_userName"/></td>
</tr>

<tr>
    <td colspan="2"><div align="right"><input type="submit" id="hello_0" value="Submit"/>
</div></td>
</tr>

</table>
</form>

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In the Hello World tutorial's example application on JSP HelloWorld.jsp was this code:

Code Block

	html	html
title	Struts Property Tag
	html


<s:property value="messageStore.message" />

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One very useful feature of the Struts 2 property tag is that it will automatically convert the most common data types (int, double, boolean) to their String equivalents. To demonstrate this feature let's add a static int variable to class HelloWorldAction.

Code Block

	java	java
title	Add Static Field
	java

private static int helloCount = 0;
	
public int getHelloCount() {
	return helloCount;
}

public void setHelloCount(int helloCount) {
	HelloWorldAction.helloCount = helloCount;
}

Each time the execute method is called we'll increase helloCount by 1. So add this code to the execute method of class HelloWorldAction.

java

Code Block

	java
title	Increase helloCount
	java


helloCount++;

Whenever a user clicks one of the links on page index.jsp (or submits the form), method execute of class HelloWorldAction will be run and the static field helloCount will be increased by one.

To include the value of the helloCount attribute in the HelloWorld.jsp we can use the Struts 2 property tag. Add the following to HelloWorld.jsp after the h2 tag.

html

Code Block

	html
title	Use Property Tag To Display helloCount Value
	html


<p>I've said hello <s:property value="helloCount" /> times!</p>

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If the value returned by the get method is an object, then the property tag will cause Struts 2 to call the object's toString method. Of course, you should always override Class Object's toString method in your model classes. Add the following toString method to the MessageStore class:

Code Block

	java	java
title	Add toString Method To Class MessageStore
	java


public String toString() {
		
	return message + " (from toString)";
		
}

Add the following to HelloWorld.jsp

Code Block

	html	html
title	Using Property Tag to Call toString
	html


<p><s:property value="messageStore" /></p>

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