Freemarker Support
Freemarker views can be rendered using the webwork result type
freemarker
.
Configure your action to use the freemarker result type
The
freemarker
result type is defined in
struts-default.xml
, so normally you just include it, and define your resuts to use
type="freemarker"
.
<include file="struts-default.xml"/>
...
<action name="test" class="package.Test">
<result name="success" type="freemarker">/WEB-INF/views/testView.ftl</result>
</action>
...
Property Resoloution
Your action properties are automatically resolved - just like in a velocity view.
for example
${name
} will result in
stack.findValue("name")
, which generaly results in
action.getName()
being executed.
A search process is used to resolve the variable, searching the following scopes in order, until a value is found :
-
freemarker variables
-
value stack
-
request attributes
-
session attributes
-
servlet context attributes
Objects in the Context
The following variables exist in the FreeMarker views
req
- the current HttpServletRequest
res
- the current HttpServletResponse
stack
- the current OgnlValueStack
ognl
- the OgnlTool instance
-
This class contains useful methods to execute OGNL expressions against arbitary objects, and a method to generate a select list using the <s:select> pattern. (i.e. taking the name of the list property, a listKey and listValue)
struts
- an instance of StrutsBeanWrapper
action
- the current Struts action
exception
- optional the Exception instance, if the view is a JSP exception or Servlet exception view
FreeMarker configuration with recent releases
To configure the freemarker engine that Struts uses, just add a file
freemarker.properties
to the classpath. The supported properties are those that the Freemarker Configuration object expects - see the Freemarker documentation^[http://freemarker.org/docs/api/freemarker/template/Configuration.html#setSetting(java.lang.String,%20java.lang.String)] for these.
default_encoding=ISO-8859-1
template_update_delay=5
locale=no_NO
Using struts UI tags - or any JSP Tag Library
Freemarker has builtin support for using any JSP taglib. You can use JSP taglibs in FreeMarker even if a) your servlet container has no support for JSP, or b) you didn’t specify the taglib in your web.xml - note how in the example below we refer to the taglib by its webapp-absolute URL, so no configuration in web.xml is needed.
<#assign s=JspTaglibs["/WEB-INF/struts.tld"] />
<@s.form method="'post'" name="'inputform'" action="'save.action'" >
<@s.hidden name="'id'" />
<@s.textarea label="'Details'" name="'details'" rows=5 cols=40 />
<@s.submit value="'Save'" align="center" />
</@s.form>
NOTE : numeric properties for tags MUST be numbers, not strings. as in the rows and cols properties above. if you use cols=”40” you will receive an exception. Other than that, the freemarker tag container behaves as you would expect.
Dynamic attributes support
You can specify dynamic attributes with Struts 2 tags like this:
<@s.textfield name="test" dynamicAttributes={"placeholder":"input","foo":"bar"}/>
or like this:
<@s.textfield name="test" placeholder="input" foo="bar"/>
and for both case, it will be parsed into:
<input type="text" name="test" value="" id="test" placeholder="input" foo="bar"/>
You can also use OGNL expressions with dynamic tags like below:
<@s.textfield name="test" placeholder="input" foo="checked: %{bar}"/>
When using attributes with hyphens, use the below syntax (you can also leave the single quotes from false if you want)
<@s.form dynamicAttributes={'data-ajax':'false'}>
...
</@s.form>