The simplegreeting CDI Example (original) (raw)
The simplegreeting
example illustrates some of the most basic features of CDI: scopes, qualifiers, bean injection, and accessing a managed bean in a JavaServer Faces application. When you run the example, you click a button that presents either a formal or an informal greeting, depending on how you edited one of the classes. The example includes four source files, a Facelets page and template, and configuration files.
The following topics are addressed here:
The simplegreeting Source Files
The four source files for the simplegreeting
example are:
- The default
Greeting
class, shown inBeans as Injectable Objects - The
@Informal
qualifier interface definition and theInformalGreeting
class that implements the interface, both shown inUsing Qualifiers - The
Printer
managed bean class, which injects one of the two interfaces, shown in full in Adding Setter and Getter Methods
The source files are located in the_tut-install_/examples/cdi/simplegreeting/src/main/java/javaeetutorial/simplegreeting
directory.
The Facelets Template and Page
To use the managed bean in a simple Facelets application:
- Use a very simple template file and
index.xhtml
page.
The template page,template.xhtml
, looks like this:
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang="en"
xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:ui="http://xmlns.jcp.org/jsf/facelets">
<h:head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
<h:outputStylesheet library="css" name="default.css"/>
<title><ui:insert name="title">Default Title</ui:insert></title>
</h:head>
<body>
<div id="container">
<div id="header">
<h2><ui:insert name="head">Head</ui:insert></h2>
</div>
<div id="space">
<p></p>
</div>
<div id="content">
<ui:insert name="content"/>
</div>
</div>
</body>
</html>
- To create the Facelets page, redefine the title and head, then add a small form to the content:
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html lang="en"
xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://xmlns.jcp.org/jsf/facelets"
xmlns:h="http://xmlns.jcp.org/jsf/html">
<ui:composition template="/template.xhtml">
<ui:define name="title">Simple Greeting</ui:define>
<ui:define name="head">Simple Greeting</ui:define>
<ui:define name="content">
<h:form id="greetme">
<p><h:outputLabel value="Enter your name: " for="name"/>
<h:inputText id="name" value="#{printer.name}"/></p>
<p><h:commandButton value="Say Hello"
action="#{printer.createSalutation}"/></p>
<p><h:outputText value="#{printer.salutation}"/> </p>
</h:form>
</ui:define>
</ui:composition>
</html>
The form asks the user to enter a name. The button is labeled Say Hello, and the action defined for it is to call the createSalutation
method of the Printer
managed bean. This method in turn calls the greet
method of the defined Greeting
class.
The output text for the form is the value of the greeting returned by the setter method. Depending on whether the default or the @Informal
version of the greeting is injected, this is one of the following, wherename
is the name entered by the user:
The Facelets page and template are located in the_tut-install_/examples/cdi/simplegreeting/src/main/webapp/
directory.
The simple CSS file that is used by the Facelets page is in the following location:
tut-install/examples/cdi/simplegreeting/src/main/webapp/resources/css/default.css
Running the simplegreeting Example
You can use either NetBeans IDE or Maven to build, package, deploy, and run the simplegreeting
application.
The following topics are addressed here:
- To Build, Package, and Run the simplegreeting Example Using NetBeans IDE
- To Build, Package, and Deploy the simplegreeting Example Using Maven
- To Run the simplegreeting Example
To Build, Package, and Run the simplegreeting Example Using NetBeans IDE
- Make sure that GlassFish Server has been started (seeStarting and Stopping GlassFish Server).
- From the File menu, choose Open Project.
- In the Open Project dialog box, navigate to:
- Select the
simplegreeting
folder. - Click Open Project.
- To modify the
Printer.java
file, perform these steps:- Expand the Source Packages node.
- Expand the
greetings
node. - Double-click the
Printer.java
file. - In the editor, comment out the
@Informal
annotation:
@Inject //@Informal Greeting greeting;
- Save the file.
- In the Projects tab, right-click the
simplegreeting
project and select Build.
This command builds and packages the application into a WAR file,simplegreeting.war
, located in thetarget
directory, and then deploys it to GlassFish Server.
To Build, Package, and Deploy the simplegreeting Example Using Maven
- Make sure that GlassFish Server has been started (seeStarting and Stopping GlassFish Server).
- In a terminal window, go to:
tut-install/examples/cdi/simplegreeting/
- Enter the following command to deploy the application:
This command builds and packages the application into a WAR file,simplegreeting.war
, located in thetarget
directory, and then deploys it to GlassFish Server.
To Run the simplegreeting Example
- In a web browser, enter the following URL:
http://localhost:8080/simplegreeting
The Simple Greeting page opens.
2. Enter a name in the field.
For example, suppose that you enter Duke
.
3. Click Say Hello.
If you did not modify the Printer.java
file, then the following text string appears below the button:
If you commented out the @Informal
annotation in the Printer.java
file, then the following text string appears below the button: