wicket deliver your webapp on time

2Copyright AlphaCSP Israel 2007 The JavaEdge Seminar

Apache Wicket Apache Wicket Deliver your web Deliver your web

application on timeapplication on timeYoav Hakman

Development Manager & Consultant, AlphaCSP


AgendaAgenda

Overview

The Wicket Way (Concepts)

Features

Demo A wicket application A custom component

Q & A


From Roi’s JSF presentation:From Roi’s JSF presentation:

Shortcomings Development

Customizing components is complicated Exceptions are not descriptive No support for annotations

Deployment Unnecessary deployment step Not JEE compliant (packaging, DI)

Components Missing components Limited component functionality (DataGrid)

Security No security model (managed beans, resources)

Ajax

JSF 1.2 (JSR 252):


OverviewOverview

• Component based Java web framework• rich component suite

• Open source (Apache 2 Licensed)• Wicket makes developing webapps simple and

enjoyable again• Flat learning curve• No XML configuration files• Very easy to create and reuse components!• Pure Object Oriented!


A little bit of historyA little bit of history

10/2004

0.9 1.0 1.1 1.2 1.3

06/2005

10/2005

05/2006

07/2007

11/2007


Good DocumentationGood Documentation

Wicket wiki:http://cwiki.apache.org/WICKET/

Wicket Examples (Live Demo + sources):http://www.wicketstuff.org/wicket13/

http://cwiki.apache.org/WICKET/

http://www.wicketstuff.org/wicket13/



JSF 2.0 (JSR 314): Purpose

Max. development productivity (IDE) Min. maintenance complexity Integrate with other web tech. More responsive UI (Ajax)

Requirements Ease of development New Features & Fixes Performance & Scalability Technology Adoption


AgendaAgenda

Overview


Features


Q & A


Wicket TemplatesWicket Templates

• HTML Templates contains • static presentation code (markup)• wicket:id attribute placeholder for wicket

components

• Forces the developer to keep “clean templates”

• The html designer has no knowledge regarding the business domain objects• vs jsf backing bean


TemplatesTemplatesJSP:

JSF:

WICKET:

<table> <tr> <c:forEach var="item" items="${sessionScope.list}"> <td> <c:out value="item.name" /> </td> </c:forEach> </tr> </table>

<h:dataTable value="#{list}" var="item"> <h:column> <h:outputText value="#{item.name}"/> </h:column> </h:dataTable>

<table> <tr> <td wicket:id=”list”> <span wicket:id=”name”>power point</span> </td> </tr> </table>


Wicket TemplatesWicket Templates

• Most existing frameworks require special HTML code.

• fully compliant with the XHTML standard, so you can use:

• Macromedia Dreamweaver• Microsoft Front Page• Any other HTML editor


If you know Java and HTML you already know a lot about Wicket!!


Linking Java and HTMLLinking Java and HTML

public class HelloWorld extends WebPage { public HelloWorld() { add(new Label("message", "Hello World!")); } }

Identifier Model

<html> <body> <span wicket:id="message" id="message">to be replaced</span> </body> </html>


Linking Java and HTMLLinking Java and HTML

HTML and Java files resides in the same classpath package


Object OrientedObject Oriented

• Object Oriented• Great for Java developers • Everything is done in Java• Swing like programming …

Form form = new Form("customerform", new CompoundPropertyModel(new Customer())); TextField zipCodeComponent = new TextField("zip"); zipCodeComponent.add(new ZipCodeValidator()); form.add(zipCodeComponent);


Application ClassApplication Class

• Settings– Application Settings– Debug Settings– Exception Settings– Markup Settings– Page Settings– RequestCycle Settings– Security Settings– Session Settings

public class DemoApplication extends WebApplication { @Override public Class getHomePage() { return HomePage.class; } @Override protected void init() { getMarkupSettings().setCompressWhitespace(false); }


Application ClassApplication Class

• The only xml configuration is the web.xml configuration!

<filter> <filtername>DemoApplication</filtername> <filterclass>org.apache.wicket.protocol.http.WicketFilter</filter <initparam> <paramname>applicationClassName</paramname> <paramvalue>com.alphacsp.DemoApplication</paramvalue> </initparam> <initparam> <paramname>configuration</paramname> <paramvalue>development</paramvalue> <! <paramvalue>deployment</paramvalue> > </initparam> </filter>








JSF 1.2 (JSR 252):


Customizing ComponentsCustomizing Components

• Object Oriented Basics – how to extend:• By Inheritance• By Delegation

public class PasswordTextField extends TextField { public PasswordTextField(String id) { super(id); } /** * Processes the component tag */ protected final void onComponentTag(final ComponentTag tag) { super.onComponentTag(tag); tag.put("value", ""); } }



public class MyComponent extends Component { protected void onAfterRender() { } protected void onBeforeRender() { } protected void onComponentTag(ComponentTag tag) { } protected void onComponentTagBody(MarkupStream markupStream, ComponentTag openTag) { } protected void onModelChanged() { } protected void onRender(MarkupStream markupStream) { } }

Component Hook Methods



• Object Oriented Basics – how to extend:• By Inheritance• By Delegation



public class SimpleAttributeModifier extends AbstractBehavior { /** * Called any time a component that has this behavior registered is * rendering the component tag. */ public void onComponentTag(final Component component, final ComponentTag tag) { if (isEnabled(component)) { tag.getAttributes().put(attribute, value); } }



TextField myText = new TextField("myText", new Model("foo")); myText.add(new SimpleAttributeModifier("class", "green"));

With the following markup: <input type="text" wicket:id="myText"/>

Would be rendered as: <input type=”text” wicket:id=”myText” name=”myText” class=”green” value=”foo”/>

SimpleAttributeModifer



item.add(new AbstractBehavior() { /** * Called any time a component that has this behavior registered is * rendering the component tag. */ public void onComponentTag(Component component, ComponentTag tag) { String css = (((Item) component).getIndex() % 2 == 0) ? "even":"odd"; tag.put("class", css); } });

Output:<tr class=“odd”>…</tr> <tr class=“even”>…</tr>



• Behaviors are used for:• Modifying attributes• Adding Java Script events• Adding Ajax Events

TextField field = new TextField("textfield", inputModel); add(field); field.add(new AjaxFormComponentUpdatingBehavior("onblur") { protected void onUpdate(AjaxRequestTarget target) { // do something here } });


AgendaAgenda

Overview


Features


Q & A








JSF 1.2 (JSR 252):


Editable tableEditable table


TableTable


Editable Tree TableEditable Tree Table


DatePickerDatePicker


CaptchaCaptcha


Modal WindowModal Window


File UploadFile Upload


Tabbed PanelTabbed Panel

<span wicket:id="tabs" class="tabpanel">[tabbed panel]</span>

List<ITab> tabs = new ArrayList<ITab>(); tabs.add(new AbstractTab(new Model("first tab")) { public Panel getPanel(String panelId) { return new TabPanel1(panelId); } }); tabs.add(new AbstractTab(new Model("second tab")) { public Panel getPanel(String panelId) { return new TabPanel2(panelId); } }); tabs.add(new AbstractTab(new Model("third tab")) { public Panel getPanel(String panelId) { return new TabPanel3(panelId); } }); add(new TabbedPanel("tabs", tabs));


Auto Complete ComponentAuto Complete Component


ModelsModels

• Holds the values of the components• Mediate between the view and domain

layer

public interface IModel { Object getObject(); void setObject(Object object); }


ModelsModels

public class HelloWorld extends WebPage { public HelloWorld() { add(new Label("message", "Hello World!")); } }

public class HelloWorld extends WebPage { public HelloWorld() { add(new Label("message", new Model("Hello World!")); } }

The data is constant


public class HelloWorld extends WebPage { public HelloWorld() { add(new TextField("name", new Model(person.getName())); } }

ModelsModels

• Immutable, not dynamic• Can produce null pointer exceptions!

person.getAddress().getCity()


ModelsModels

• Dynamic• Inconvenient!

personForm.add(new TextField("personName", new IModel() { public Object getObject() { return person.getName(); } public void setObject(Serializable serializable) { person.setName((String) serializable); } }));


ModelsModels

• The expression language is more compact than the analogous Java code

• Simpler than to subclass a Model• No null pointer exceptions

– “person.address.city”

new TextField("personName", new PropertyModel(person, "name"));


ModelsModels

Adds property expressions and MessageFormat substitutions

StringResourceModel

Used for retrieving messages from resource bundles

ResourceModel

Used for large data setsLoadableDetachableModel

Uses component identidiers as property expressions

CompoundPropertyModel

Uses a property expression to dynamically access a property in your domain objects

PropertyModel

Wraps a serializable objectModelDescriptionModel








JSF 1.2 (JSR 252):


descriptive exceptions!descriptive exceptions!


More FeaturesMore Features

• Ajax Debug Window– Shows the ajax request and response– Shows exceptions

• Integration with other frameworks• Spring• Juice• Seam 2.0• Acegi Security

• Nice and Secure URL’s


SessionsSessions

• Strongly Typed Sessions

public class MySession extends WebSession { private String myAttribute; private ShoppingCart cart; private UserDetails userDetails; public MySession(WebApplication application) { super(application); } // ... getters and setters }


LocalizationLocalization

• String Resource Search Order:• Component• Panel (parent)• Page • Application


AgendaAgenda

Overview


Features


Q & A


Q&AQ&A

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