This tag library provides tiles tags.

Tiles were previously called Components. For historical reasons, names, pages, components and templates are used indifferently to design a tile. Also, a lot of tags and attribute names are left for backward compatibility.
To know more about tags defined in this library, check the associated documentation: tiles-doc.

Tag Name	Description
add	Add an element to the surrounding list. Equivalent to 'put', but for list element.
definition	Create a tile /component / template definition bean.
get	Gets the content from request scope that was put there by a put tag.
getAsString	Render the value of the specified tile/component/template attribute to the current JspWriter
importAttribute	Import Tile's attribute in specified context.
initComponentDefinitions	Initialize Tile/Component definitions factory.
insert	Insert a tiles/component/template.
put	Put an attribute into tile/component/template context.
putList	Declare a list that will be pass as attribute to tile.
useAttribute	Use attribute value inside page.

Add an element to the surrounding list. This tag can only be used inside putList tag. Value can come from a direct assignment (value="aValue") or from a bean. One of 'value' or 'beanName' must be present.

Attribute Name	Description
beanName	Name of the bean used as value. Bean is retrieved from specified context, if any. Otherwise, method pageContext.findAttribute is used. If beanProperty is specified, retrieve value from the corresponding bean property. (RT EXPR)
beanProperty	Bean property name. If specified, value is retrieve from this property. Support nested/indexed properties. (RT EXPR)
beanScope	Scope into which bean is searched. If not specified, method pageContext.findAttribute is used. Scope can be any JSP scope, 'component', or 'template'. In these two later cases, bean is search in tile/component/template context.
content	Element value. Can be a String or Object. Synonym to value. Attribute added for compatibility with JSP Template. (RT EXPR)
direct	Determines how content is handled: true means content is printed directly; false, the default, means content is included. This is another way to specify content type. If 'direct=true' content is 'string', if 'direct=false', content is 'page'. Attribute added for compatibility with JSP Template.
role	If the user is in the specified role, the tag is taken into account; otherwise, the tag is ignored (skipped). The role isn't taken into account if <add> tag is used in a definition. (RT EXPR)
type	Specify content type: string, page, template or instance. String : Content is printed directly. page | template : Content is included from specified URL. Name is used as an URL. definition : Value denote a definition defined in factory (xml file). Definition will be searched in the inserted tile, in a <insert attribute="attributeName"> tag, where 'attributeName' is the name used for this tag. If 'type' attribute is not specified, content is 'untyped', unless it comes from a typed bean.
value	Element value. Can be a String or Object.

Create a tile/component/template definition as a bean. Newly created bean will be saved under specified "id", in the requested "scope". Definition tag has same syntax as insert tag. The new definition can extends a definition described in factory (XML file), and overload any previously defined parameters.

Attribute Name	Description
extends	Name of a parent definition that is used to initialize this new definition. Parent definition is searched in definitions factory. (RT EXPR)
id	Specifies the name under which the newly created definition bean will be saved. (REQUIRED)
page	URL of the template / component to insert. Same as "template". (RT EXPR)
role	Role to check before inserting this definition. If role is not defined for current user, definition is not inserted. Checking is done at insert time, not during definition process. (RT EXPR)
scope	Specifies the variable scope into which the newly defined bean will be created. If not specified, the bean will be created in page scope.
template	A string representing the URI of a tile/component/template (a JSP page). (RT EXPR)

Retrieve content from tile context and include it.
Take into account the 'type' attribute.

Attribute Name	Description
flush	True or false. If true, current page out stream is flushed before insertion.
ignore	If this attribute is set to true, and the attribute specified by the name does not exist, simply return without writing anything. The default value is false, which will cause a runtime exception to be thrown. (RT EXPR)
name	The name of the content to get from tile/component scope. (REQUIRED) (RT EXPR)
role	If the user is in the specified role, the tag is taken into account; otherwise, the tag is ignored (skipped). (RT EXPR)

Retrieve the value of the specified tile/component/template attribute property, and render it to the current JspWriter as a String. The usual toString() conversions is applied on found value.
Throw a JSPException if named value is not found.

Attribute Name	Description
ignore	If this attribute is set to true, and the attribute specified by the name does not exist, simply return without writing anything. The default value is false, which will cause a runtime exception to be thrown. (RT EXPR)
name	Attribute name. (REQUIRED) (RT EXPR)
role	If the user is in the specified role, the tag is taken into account; otherwise, the tag is ignored (skipped). (RT EXPR)

Import attribute from tile to requested scope. Attribute name and scope are optional. If not specified, all tile attributes are imported in page scope. Once imported, an attribute can be used as any other beans from jsp contexts.

Attribute Name	Description
ignore	If this attribute is set to true, and the attribute specified by the name does not exist, simply return without error. The default value is false, which will cause a runtime exception to be thrown. (RT EXPR)
name	Tile's attribute name. If not specified, all attributes are imported. (RT EXPR)
scope	Scope into which attribute is imported. Default to page.

Initialize Tile/Components definitions factory.
In order to use Tile/Component definitions factory, you need to initialize the factory. This is generally done in a initializing servlet. In particular, it is done in "ComponentActionServlet" if you use it. If you don't initialize factory in a servlet, you can initialize it using this tag. You need to provide the description file name, and optionally the factory classname. Initialization is done only once, at the first call of this tag. Subsequent calls are ignored (tag checks existence of the factory.

Attribute Name	Description
classname	If specified, classname of the factory to create and initialized.
file	Definition file name. (REQUIRED)

Insert a tiles/component/template with the possibility to pass parameters (called attribute). A tile can be seen as a procedure that can take parameters or attributes. <template:insert> allows to define these attributes and pass them to the inserted jsp page, called template. Attributes are defined using nested tag <template:put> or <template:putList>.
You must specify one of this tag attribute :

• template, for inserting a tiles/component/template page,
• component, for inserting a tiles/component/template page, (same as template)
• page for inserting a JSP page, (same as template)
• definition, for inserting a definition from definitions factory
• attribute, surrounding tiles's attribute name whose value is used.
  If attribute is associated to 'direct' flag (see put), and flag is true, write attribute value (no insertion).
  
• name, to let 'insert' determine the type of entities to insert. In this later case, search is done in this order : definitions, tiles/components/templates, pages.

In fact, Page, component and template, are equivalent as a tile, component or template are jsp page.
Example :

          <template:insert page="/basic/myLayout.jsp" flush="true">
            <template:put name="title"  value="My first page" />
            <template:put name="header" value="/common/header.jsp" />
            <template:put name="footer" value="/common/footer.jsp" />
            <template:put name="menu"   value="/basic/menu.jsp" />
            <template:put name="body"   value="/basic/helloBody.jsp" />
          </template:insert>

Attribute Name	Description
attribute	Name of an attribute in current tile/component context. Value of this attribute is passed to 'name' (see attribute 'name').
beanName	Name of the bean used as value. Bean is retrieved from specified context, if any. Otherwise, method pageContext.findAttribute is used. If beanProperty is also specified, retrieve value from the corresponding bean property. If found bean (or property value) is instance of one of Attribute class (Direct, Instance, ...), insertion is done according to the class type. Otherwise, the toString method is called on the bean, and returned String is used as name to insert (see 'name' attribute). (RT EXPR)
beanProperty	Bean property name. If specified, value is retrieve from this property. Support nested/indexed properties. (RT EXPR)
beanScope	Scope into which bean is searched. If not specified, method pageContext.findAttribute is used. Scope can be any JSP scope, 'component', or 'template'. In these two later cases, bean is search in tile/component/template context.
component	Path (relative or absolute to webapps) of the component to insert. 'page', 'component' and 'template' are synonyms : they have exactly the same behavior. (RT EXPR)
controllerClass	Class type of a controller called immediately before page is inserted. Controller is used to prepare data to be render by inserted Tile. See also controlerUrl Class must implements or extends one of the following : org.apache.struts.tiles.Controller org.apache.struts.tiles.ControllerSupport org.apache.struts.action.Action (wrapper org.apache.struts.action.ActionController is used) See also controllerUrl. Only one of controllerUrl or controllerClass should be used. (RT EXPR)
controllerUrl	Url of a controller called immediately before page is inserted. Url usually denote a Struts action. Controller (action) is used to prepare data to be render by inserted Tile. See also controlerClass. Only one of controllerUrl or controllerClass should be used. (RT EXPR)
definition	Name of the definition to insert. Definition are defined in a centralized file. For now, only definition from factory can be inserted with this attribute. To insert a definition defined with tag <template:definition>, use beanName="". (RT EXPR)
flush	True or false. If true, current page out stream is flushed before insertion.
ignore	If this attribute is set to true, and the attribute specified by the name does not exist, simply return without writing anything. The default value is false, which will cause a runtime exception to be thrown. (RT EXPR)
name	Name of an entity to insert. Search is done in this order : definition, attribute, [tile/component/template/page]. (RT EXPR)
page	Path (relative or absolute to webapps) of the page to insert. 'page', 'component' and 'template' are synonyms : they have exactly the same behavior. (RT EXPR)
role	If the user is in the specified role, the tag is taken into account; otherwise, the tag is ignored (skipped). (RT EXPR)
template	A string representing the URI of a tile or template (a JSP page). 'page', 'component' and 'template' are synonyms : they have exactly the same behavior. (RT EXPR)

Define an attribute to pass to tile/component/template. This tag can only be used inside 'insert' or 'definition' tag. Value (or content) is specified using attribute 'value' (or 'content'), or using the tag body. It is also possible to specify the type of the value :

• string : Content is written directly.
• page | template : Content is included from specified URL. Name is used as an URL.
• definition : Content come from specified definition (from factory). Name is used as definition name.

If type is specified, it is taken into account by 'get' or 'insert' inside the inserted tile.
If 'type' attribute is not specified, content is 'untyped', unless it comes from a typed bean.
Note that using 'direct="true"' is equivalent to 'type="string"'.

Attribute Name	Description
beanName	Name of the bean used as value. Bean is retrieved from specified context, if any. Otherwise, method pageContext.findAttribute is used. If beanProperty is specified, retrieve value from the corresponding bean property. (RT EXPR)
beanProperty	Bean property name. If specified, value is retrieve from this property. Support nested/indexed properties. (RT EXPR)
beanScope	Scope into which bean is searched. If not specified, method pageContext.findAttribute is used. Scope can be any JSP scope, 'tile', 'component', or 'template'. In these three later cases, bean is search in tile/component/template context.
content	Content that's put into tile scope. Synonym to value. Attribute added for compatibility with JSP Template. (RT EXPR)
direct	Determines how content is handled: true means content is printed directly; false, the default, means content is included. This is another way to specify content type. If 'direct=true' content is 'string', if 'direct=false', content is 'page'. Attribute added for compatibility with JSP Template.
name	Name of the attribute.
role	If the user is in the specified role, the tag is taken into account; otherwise, the tag is ignored (skipped). (RT EXPR)
type	Specify content type: string, page, template or definition. String : Content is printed directly. page | template : Content is included from specified URL. Name is used as an URL. definition : Value is the name of a definition defined in factory (xml file). Definition will be searched in the inserted tile, in a <template:insert attribute="attributeName"> tag, where 'attributeName' is the name used for this tag. If 'type' attribute is not specified, content is 'untyped', unless it comes from a typed bean.
value	Attribute value. Could be a String or an Object. Value can come from a direct assignment (value="aValue") or from a bean. One of 'value' 'content' or 'beanName' must be present. (RT EXPR)

Declare a list that will be pass as attribute to tile. List elements are added using the tag 'add'. This tag can only be used inside 'insert' or 'definition' tag.

Attribute Name	Description
name	Name of the list. (REQUIRED)

Declare a Java variable, and an attribute in the specified scope, using tile attribute value.
Java variable and attribute will have the name specified by 'id', or the original name if not specified.

Attribute Name	Description
classname	Class of the declared variable.
id	Declared attribute and variable name.
ignore	If this attribute is set to true, and the attribute specified by the name does not exist, simply return without error. The default value is false, which will cause a runtime exception to be thrown. (RT EXPR)
name	Tile's attribute name. (REQUIRED) (RT EXPR)
scope	Scope of the declared attribute. Default to 'page'.