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# Freemarker Support

Freemarker views can be rendered using a 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 results 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 Resolution

Your action properties are automatically resolved - just like in a velocity view.

for example

`${name}` will result in `stack.findValue("name")`, which generally 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 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

- your servlet container has no support for JSP, or
- 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>