com.communote.server.widgets

Class WidgetController<V>

java.lang.Object

com.communote.server.widgets.WidgetController<V>

Type Parameters:

V - the type of view the controller supports

Direct Known Subclasses:

SimpleWidgetController, SpringMVCWidgetController

public abstract class WidgetController<V>
extends Object

Controller for widget requests.

The controller creates a new Widget instance which will be invoked to handle the request. The instance is created with the help of a configurable WidgetFactory which is by default an instance of SimpleWidgetFactory. The factory is passed the group and the type name of the widget and additionally has access to the request parameters to select and instantiate the correct widget class. The widget group and name can be provided as request parameters named 'widgetGroup' and 'widget'. Alternatively they can be part of the request URL which is expected to look like /widgets/widgetGroup/widgetTypeName.widget The widgetGroup can contain slashes (in both variants) for further structuring. Whether to parse the URL or check the parameters for group and name can be defined with setUseRequestParametersForWidget(boolean). URL parsing is the default.

Author:

Communote GmbH - http://www.communote.com/

Field Summary

Fields

Modifier and Type	Field and Description
static String	OBJECT_LIST object list identifier in the view: If the result is a list it will be available in the request after the widgets handleRequest has been called
static String	OBJECT_SINGLE single object result identifier in the view: If it the widgets result is a single reslult it will be available in the request after the widgets handleRequest has been called
static String	OBJECT_WIDGET Widget identifier in the view: It will be available in the request after the widgets handleRequest has been called
static String	WIDGET_TYPE widget type identifier (e.g.

Constructor Summary

Constructors

Constructor and Description
WidgetController() Default constructor

Method Summary

Modifier and Type	Method and Description
protected abstract V	createMultiResultView(javax.servlet.http.HttpServletRequest request, Widget widget, List<?> result) Creates and prepares the view to render the response of the widget request.
protected abstract V	createSingleResultView(javax.servlet.http.HttpServletRequest request, Widget widget, Object result) Creates and prepares the view to render the response of the widget request.
protected Widget	getWidgetInstance(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) Get the widget for the given request and configure it
V	handleWidgetRequest(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) Parses the request, extracts the widget and invokes its query method.
void	setAppendWidgetToTypeName(boolean appendWidget) Whether to append the static string 'Widget' to all widget type names provided by URL or request parameter.
void	setUseRequestParametersForWidget(boolean useRequestParametersForWidget) Determines how a widget is found.
void	setWidgetFactory(WidgetFactory factory) Set the factory to use for creating an instance of a widget that should handle a widget request.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

WIDGET_TYPE

public static final String WIDGET_TYPE

widget type identifier (e.g. dhtml)

See Also:

Constant Field Values

OBJECT_SINGLE

public static final String OBJECT_SINGLE

single object result identifier in the view: If it the widgets result is a single reslult it will be available in the request after the widgets handleRequest has been called

See Also:

Constant Field Values

OBJECT_LIST

public static final String OBJECT_LIST

object list identifier in the view: If the result is a list it will be available in the request after the widgets handleRequest has been called

See Also:

Constant Field Values

OBJECT_WIDGET

public static final String OBJECT_WIDGET

Widget identifier in the view: It will be available in the request after the widgets handleRequest has been called

See Also:

Constant Field Values

Constructor Detail

WidgetController

public WidgetController()

Default constructor

Method Detail

createMultiResultView

protected abstract V createMultiResultView(javax.servlet.http.HttpServletRequest request,
                                           Widget widget,
                                           List<?> result)

Creates and prepares the view to render the response of the widget request. This method is invoked if the widget is expected to return a list of items.

Parameters:

request - the request

widget - the widget that was invoked

result - the result returned from the query method of the widget

Returns:

the view

createSingleResultView

protected abstract V createSingleResultView(javax.servlet.http.HttpServletRequest request,
                                            Widget widget,
                                            Object result)

Creates and prepares the view to render the response of the widget request. This method is invoked if the widget is expected to return a single item.

Parameters:

request - the request

widget - the widget that was invoked

result - the result returned from the query method of the widget

Returns:

the view

getWidgetInstance

protected Widget getWidgetInstance(javax.servlet.http.HttpServletRequest request,
                                   javax.servlet.http.HttpServletResponse response)

Get the widget for the given request and configure it

Parameters:

request - The request

response - the response to use

Returns:

the configured widget

handleWidgetRequest

public V handleWidgetRequest(javax.servlet.http.HttpServletRequest request,
                             javax.servlet.http.HttpServletResponse response)

Parses the request, extracts the widget and invokes its query method. The result of the query will be used to prepare a view. The created view will be returned and can be passed to a rendering engine. The view creation is delegated to createSingleResultView(HttpServletRequest, Widget, Object) or createMultiResultView(HttpServletRequest, Widget, List) depending on the expected result type of the widget.

Parameters:

request - the request

response - the response

Returns:

the view

setAppendWidgetToTypeName

public void setAppendWidgetToTypeName(boolean appendWidget)

Whether to append the static string 'Widget' to all widget type names provided by URL or request parameter. Defaults to false.

Parameters:

appendWidget - true to append the static string

setUseRequestParametersForWidget

public void setUseRequestParametersForWidget(boolean useRequestParametersForWidget)

Determines how a widget is found. If true the request parameters widgetGroup and widget are used to determine the widget group and widget type name. Otherwise the URL is parsed and is expected to look like /widgets/widgetGroupName/widgetTypeName.widget.

Parameters:

useRequestParametersForWidget - true if the request parameters should be used

setWidgetFactory

public void setWidgetFactory(WidgetFactory factory)

Set the factory to use for creating an instance of a widget that should handle a widget request.

Parameters:

factory - the factory to use