Best Frameworks: Wicket+Spring Basic Example

Welcome to my first post on this blog!
The purpose of my first tutorial will be to present a basic example of how to use some of the most popular Java frameworks, at the same time: Spring & Wicket. So we start step by step...

1. We need to create a Maven-webapp

2. Update Maven dependencies

Open your pom.xml file and update your dependencies section as below:


    
      junit
      junit
      3.8.1
      test
    
    
     org.apache.wicket
     wicket
     6.9.1
     pom
    
    
     javax.servlet
     javax.servlet-api
     3.1.0
    
    
     org.springframework
     spring-context
     3.2.3.RELEASE
    
    
     org.springframework
     spring-web
     3.2.3.RELEASE
    
    
     org.apache.wicket
     wicket-spring
     6.9.1
    
    
     org.apache.wicket
     wicket-request
     6.9.1
    
    
     org.slf4j
     slf4j-log4j12
     1.7.5

3. Now take a look on the project structure to make things a little bit clear

4. Last thing about configuration is the spring application context file and then everything will be great and we'll start talking about code, but we have to agree that in this case the configuration is a very important part of our project and we need to do it very carefully

WEB-INF/applicationContext.xml file should be something like this

5. Now it's code time...

First, please update the main web application file and override the init method from org.apache.wicket.protocol.http.WebApplication class and then the web.xml file:

public class WicketApp extends WebApplication{

 @Override
 public Class getHomePage() {
  // TODO Auto-generated method stub
  return Index.class;
 }

 @Override
 protected void init()
 {
  super.init();
  //getDebugSettings().setDevelopmentUtilitiesEnabled(true);
  getComponentInstantiationListeners().add(new SpringComponentInjector(this));
 }
}

File: web.xml


 Wicket Web Application
 
 
  wicket.wicketTest
  org.apache.wicket.protocol.http.WicketFilter
  
   applicationClassName
   com.wicket.tutorials.blogspot.WicketApp
  
 
 
 
  wicket.wicketTest
  /*
 
 
  
  
           org.springframework.web.context.ContextLoaderListener

Next I will create a very simple service example, with only one method which will return a Hello entity

**Service interface

public interface HelloService {

 Hello getHelloMessage(String name); 
}

**Service implementation

@Service
public class HelloServiceImpl implements HelloService {

 public Hello getHelloMessage(String name) {
  // TODO Auto-generated method stub
  
  return new Hello(name);
 }

}

Notes
*You can also create other components writing your own beans in applicationContext.xml file, or using annotations like @Repository or @Component and inject them in the same way, with @SpringBean

We are so close to finish this long example and for this we need only web pages and everything will be done. I will not start to explain to much the wicket code, how can we add page parameters or how can we add events on input for example, but Index page is an example of how to use this wicket features

File: Index.html

<html>
<head>
 
</head>
<body>



 


</body>
</html>

File: Index.java

public class Index extends WebPage{
 
 public Index()
 {
  this(new PageParameters());
 }
 
 public Index(PageParameters parameters)
 {
  final PageParameters helloPage_Parameters=new PageParameters();
  helloPage_Parameters.add("message", "");
  
  add(new Label("PageTitle", "Index Page"));
  
        Form form = new Form("form");
        add(form);

        final TextField field = new TextField("person", new Model(""));
        form.add(field);
  
        
        OnChangeAjaxBehavior onChangeAjaxBehavior = new OnChangeAjaxBehavior()
        {
            @Override
            protected void onUpdate(AjaxRequestTarget target)
            {
                helloPage_Parameters.set("message", field.getValue());
            }
        };
        field.add(onChangeAjaxBehavior);
        
  Link link=new Link("action-link") {

   @Override
   public void onClick() {
      
       setResponsePage(new HelloPage(helloPage_Parameters));
    
   }
  };
  
  link.add(new Label("message","Say Hello"));
  
  add(link);
 }
}

File: HelloPage.html

<html>
<head>
 
</head>
<bodyl>

</body>
</html>

File: HelloPage.java

public class HelloPage extends WebPage{

 @SpringBean
 private HelloService helloService;
 
 public HelloPage()
 {
  
 }
 
 public HelloPage(PageParameters pageParameters)
 {
  add(new Label("PageTitle", "Hello Page"));
  
  Hello hello=helloService.getHelloMessage(pageParameters.get("message").toString());
  
  add(new Label("hello-message",hello.toString()));
 }
}

And here we have a great example of using dependency injection with Wicket and Spring. We can refer every bean we created, using just @SpringBean annotation

Have a nice day with Java Frameworks!

2 comments:

AnonymousMarch 14, 2014 at 2:40 AM
it would be fine it is crud operation.
AnonymousAugust 24, 2015 at 3:53 AM
Hi,
I am getting this error :
Last cause: Null or empty component ID's are not allowed.
WicketMessage: Can't instantiate page using constructor 'public com.registration.pages.Index()'. An exception has been thrown during construction!

Tuesday, July 23, 2013

Wicket+Spring Basic Example