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documentation examples changes amber (jpa) ejb database ioc jmx jsf messaging quercus remoting servlet security jsf/webbeans | jsf with webbeans
WebBeans (JSR-299) gives JSF a solid foundation for its component model, based on WebBeans' typesafe IoC capabilities and annotation-based discovery.
WebBeans works together with JSF to provide a solid component-basis for the data model of a JSF application. With WebBeans, data components can be created by marking them with a @Component annotation, reducing the amount of configuration XML to a minimum. In this example, we only need XML to define the FacesServlet, and a marker web-beans.xml to direct WebBeans to search for component classes. The data components automatically populate the JSF EL (expression language), so they are automatically available to the JSF application. This example creates a simple calculator which adds two numbers together.
The The data model is the heart of the JSF application. In this case, a trivial calculator. The The Calculator.java package example; import javax.webbeans.*; @Component @RequestScoped @Named("calc") public class Calculator { private int _a; private int _b; public int getA() { return _a; } public void setA(int a) { _a = a; } public int getB() { return _b; } public void setB(int b) { _b = b; } public int getSum() { return _a + _b; } } The The optional WebBeans components can also be injected with other WebBeans, or
DataSources, JPA EntityManager or EntityManagerFactory
or JMS Queues, and they can also use the JSF is designed around a UI component tree model. The JSP code builds the JSF component tree, hands it back to JSF, and then JSF will display the component tree based on its current rendering configuration.
test.jsp <%@ taglib prefix="f" uri="http://java.sun.com/jsf/core" %> <%@ taglib prefix="h" uri="http://java.sun.com/jsf/html" %> <f:view> <h:messages/> <h:form> <h:inputText value="#{calc.a}" size="4"/> + <h:inputText value="#{calc.b}" size="4"/> = <h:outputText value="#{calc.sum}" style="color:red"/> <br> <h:commandButton value="Add"/> </h:form> </f:view> The JSF expression language expressions The housekeeping overhead is a minimum when using WebBeans. In this example we just need two pieces of XML configuration:
WebBeans will scan classes directories and jars if they contain
a WEB-INF/resin-web.xml <web-app xmlns="http://caucho.com/ns/resin"> <servlet-mapping url-pattern="*.jsf" servlet-class="javax.faces.webapp.FacesServlet"/> </web-app> META-INF/web-beans.xml <web-beans xmlns="http://caucho.com/ns/resin"> <!-- - The web-beans.xml marks a class root for WebBeans to search for - @Component beans. Since the example doesn't need to override any - defaults, there's no additional configuration necessary. --> </web-beans> A more complete application would likely the IoC injection capabilities of WebBeans. For example:
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