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<div id="preamble">
<div class="sectionbody">
<div class="paragraph">
<p><a id="GJCXV"></a><a id="the-guessnumber-cdi-cdi-example"></a></p>
<div class="sect1">
<h2 id="_the_guessnumber_cdi_cdi_example">The guessnumber-cdi CDI Example</h2>
<div class="sectionbody">
<div class="paragraph">
<p>The <code>guessnumber-cdi</code> example, somewhat more complex than the
<code>simplegreeting</code> example, illustrates the use of producer methods and of
session and application scope. The example is a game in which you try to
guess a number in fewer than ten attempts. It is similar to the
<code>guessnumber-jsf</code> example described in
<a href="jsf-facelets.html#GIEPX">Chapter 8, "Introduction to Facelets"</a>,
except that you can keep guessing until you get the right answer or
until you use up your ten attempts.</p>
<div class="paragraph">
<p>The example includes four source files, a Facelets page and template,
and configuration files. The configuration files and the template are
the same as those used for the <code>simplegreeting</code> example.</p>
<div class="paragraph">
<p>The following topics are addressed here:</p>
<div class="ulist">
<p><a href="#GJDJU">The guessnumber-cdi Source Files</a></p>
<p><a href="#GJDON">The Facelets Page</a></p>
<p><a href="#GJDPW">Running the guessnumber-cdi Example</a></p>
<div class="paragraph">
<p><a id="GJDJU"></a><a id="the-guessnumber-cdi-source-files"></a></p>
<div class="sect2">
<h3 id="_the_guessnumber_cdi_source_files">The guessnumber-cdi Source Files</h3>
<div class="paragraph">
<p>The four source files for the <code>guessnumber-cdi</code> example are:</p>
<div class="ulist">
<p>The <code>@MaxNumber</code> qualifier interface</p>
<p>The <code>@Random</code> qualifier interface</p>
<p>The <code>Generator</code> managed bean, which defines producer methods</p>
<p>The <code>UserNumberBean</code> managed bean</p>
<div class="paragraph">
<p>The source files are located in the
<code><em>tut-install</em>/examples/cdi/guessnumber-cdi/src/main/java/javaeetutorial/guessnumber</code>
directory.</p>
<div class="paragraph">
<p><a id="GJDJP"></a><a id="the-maxnumber-and-random-qualifier-interfaces"></a></p>
<div class="sect3">
<h4 id="_the_maxnumber_and_random_qualifier_interfaces">The @MaxNumber and @Random Qualifier Interfaces</h4>
<div class="paragraph">
<p>The <code>@MaxNumber</code> qualifier interface is defined as follows:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">package guessnumber;
import java.lang.annotation.Documented;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.PARAMETER;
import static java.lang.annotation.ElementType.TYPE;
import java.lang.annotation.Retention;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import java.lang.annotation.Target;
import javax.inject.Qualifier;
@Target({TYPE, METHOD, PARAMETER, FIELD})
@Retention(RUNTIME)
@Documented
public @interface MaxNumber {
}</code></pre>
<div class="paragraph">
<p>The <code>@Random</code> qualifier interface is defined as follows:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">package guessnumber;
import java.lang.annotation.Documented;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.PARAMETER;
import static java.lang.annotation.ElementType.TYPE;
import java.lang.annotation.Retention;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import java.lang.annotation.Target;
import javax.inject.Qualifier;
@Target({TYPE, METHOD, PARAMETER, FIELD})
@Retention(RUNTIME)
@Documented
public @interface Random {
}</code></pre>
<div class="paragraph">
<p><a id="GJDJN"></a><a id="the-generator-managed-bean"></a></p>
<div class="sect3">
<h4 id="_the_generator_managed_bean">The Generator Managed Bean</h4>
<div class="paragraph">
<p>The <code>Generator</code> managed bean contains the two producer methods for the
application. The bean has the <code>@ApplicationScoped</code> annotation to specify
that its context extends for the duration of the user&#8217;s interaction with
the application:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">package guessnumber;
import java.io.Serializable;
import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.inject.Produces;
@ApplicationScoped
public class Generator implements Serializable {
    private static final long serialVersionUID = -7213673465118041882L;
    private final java.util.Random random =
        new java.util.Random( System.currentTimeMillis() );
    private final int maxNumber = 100;
    java.util.Random getRandom() {
        return random;
    @Produces @Random int next() {
        return getRandom().nextInt(maxNumber + 1);
    @Produces @MaxNumber int getMaxNumber() {
        return maxNumber;
}</code></pre>
<div class="paragraph">
<p><a id="GJDHY"></a><a id="the-usernumberbean-managed-bean"></a></p>
<div class="sect3">
<h4 id="_the_usernumberbean_managed_bean">The UserNumberBean Managed Bean</h4>
<div class="paragraph">
<p>The <code>UserNumberBean</code> managed bean, the managed bean for the JavaServer
Faces application, provides the basic logic for the game. This bean does
the following:</p>
<div class="ulist">
<p>Implements setter and getter methods for the bean fields</p>
<p>Injects the two qualifier objects</p>
<p>Provides a <code>reset</code> method that allows you to begin a new game after
you complete one</p>
<p>Provides a <code>check</code> method that determines whether the user has guessed
the number</p>
<p>Provides a <code>validateNumberRange</code> method that determines whether the
user&#8217;s input is correct</p>
<div class="paragraph">
<p>The bean is defined as follows:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">package guessnumber;
import java.io.Serializable;
import javax.annotation.PostConstruct;
import javax.enterprise.context.SessionScoped;
import javax.enterprise.inject.Instance;
import javax.faces.application.FacesMessage;
import javax.faces.component.UIComponent;
import javax.faces.component.UIInput;
import javax.faces.context.FacesContext;
import javax.inject.Inject;
import javax.inject.Named;
@SessionScoped
public class UserNumberBean implements Serializable {
    private static final long serialVersionUID = -7698506329160109476L;
    private int number;
    private Integer userNumber;
    private int minimum;
    private int remainingGuesses;
    @MaxNumber
    @Inject
    private int maxNumber;
    private int maximum;
    @Random
    @Inject
    Instance&lt;Integer&gt; randomInt;
    public UserNumberBean() {
    public int getNumber() {
        return number;
    public void setUserNumber(Integer user_number) {
        userNumber = user_number;
    public Integer getUserNumber() {
        return userNumber;
    public int getMaximum() {
        return (this.maximum);
    public void setMaximum(int maximum) {
        this.maximum = maximum;
    public int getMinimum() {
        return (this.minimum);
    public void setMinimum(int minimum) {
        this.minimum = minimum;
    public int getRemainingGuesses() {
        return remainingGuesses;
    public String check() throws InterruptedException {
        if (userNumber &gt; number) {
            maximum = userNumber - 1;
        if (userNumber &lt; number) {
            minimum = userNumber + 1;
        if (userNumber == number) {
            FacesContext.getCurrentInstance().addMessage(null,
                new FacesMessage("Correct!"));
        remainingGuesses--;
        return null;
    @PostConstruct
    public void reset() {
        this.minimum = 0;
        this.userNumber = 0;
        this.remainingGuesses = 10;
        this.maximum = maxNumber;
        this.number = randomInt.get();
    public void validateNumberRange(FacesContext context,
                                    UIComponent toValidate,
                                    Object value) {
        int input = (Integer) value;
        if (input &lt; minimum || input &gt; maximum) {
            ((UIInput) toValidate).setValid(false);
            FacesMessage message = new FacesMessage("Invalid guess");
            context.addMessage(toValidate.getClientId(context), message);
}</code></pre>
<div class="paragraph">
<p><a id="GJDON"></a><a id="the-facelets-page"></a></p>
<div class="sect2">
<h3 id="_the_facelets_page">The Facelets Page</h3>
<div class="paragraph">
<p>This example uses the same template that the <code>simplegreeting</code> example
uses. The <code>index.xhtml</code> file, however, is more complex.</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">&lt;?xml version='1.0' encoding='UTF-8' ?&gt;
&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
          "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;
&lt;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"&gt;
    &lt;ui:composition template="/template.xhtml"&gt;
        &lt;ui:define name="title"&gt;Guess My Number&lt;/ui:define&gt;
        &lt;ui:define name="head"&gt;Guess My Number&lt;/ui:define&gt;
        &lt;ui:define name="content"&gt;
            &lt;h:form id="GuessMain"&gt;
                &lt;div style="color: black; font-size: 24px;"&gt;
                    &lt;p&gt;I'm thinking of a number from
                    &lt;span style="color: blue"&gt;#{userNumberBean.minimum}&lt;/span&gt;
                    &lt;span style="color: blue"&gt;#{userNumberBean.maximum}&lt;/span&gt;.
                    You have
                    &lt;span style="color: blue"&gt;
                        #{userNumberBean.remainingGuesses}
                    &lt;/span&gt;
                    guesses.&lt;/p&gt;
                &lt;/div&gt;
                &lt;h:panelGrid border="0" columns="5" style="font-size: 18px;"&gt;
                    &lt;h:outputLabel for="inputGuess"&gt;Number:&lt;/h:outputLabel&gt;
                    &lt;h:inputText id="inputGuess"
                                 value="#{userNumberBean.userNumber}"
                                 required="true" size="3"
disabled="#{userNumberBean.number eq userNumberBean.userNumber or userNumberBean.remainingGuesses le 0}"
                               validator="#{userNumberBean.validateNumberRange}"&gt;
                    &lt;/h:inputText&gt;
                    &lt;h:commandButton id="GuessButton" value="Guess"
                                     action="#{userNumberBean.check}"
disabled="#{userNumberBean.number eq userNumberBean.userNumber or userNumberBean.remainingGuesses le 0}"/&gt;
                    &lt;h:commandButton id="RestartButton" value="Reset"
                                     action="#{userNumberBean.reset}"
                                     immediate="true" /&gt;
                    &lt;h:outputText id="Higher" value="Higher!"
rendered="#{userNumberBean.number gt userNumberBean.userNumber and userNumberBean.userNumber ne 0}"
                                  style="color: #d20005"/&gt;
                    &lt;h:outputText id="Lower" value="Lower!"
rendered="#{userNumberBean.number lt userNumberBean.userNumber and userNumberBean.userNumber ne 0}"
                                  style="color: #d20005"/&gt;
                &lt;/h:panelGrid&gt;
                &lt;div style="color: #d20005; font-size: 14px;"&gt;
                    &lt;h:messages id="messages" globalOnly="false"/&gt;
                &lt;/div&gt;
            &lt;/h:form&gt;
        &lt;/ui:define&gt;
    &lt;/ui:composition&gt;
&lt;/html&gt;</code></pre>
<div class="paragraph">
<p>The Facelets page presents the user with the minimum and maximum values
and the number of guesses remaining. The user&#8217;s interaction with the
game takes place within the <code>panelGrid</code> table, which contains an input
field, <strong>Guess</strong> and <strong>Reset</strong> buttons, and a field that appears if the guess is
higher or lower than the correct number. Every time the user clicks
<strong>Guess</strong>, the <code>userNumberBean.check</code> method is called to reset the
maximum or minimum value or, if the guess is correct, to generate a
<code>FacesMessage</code> to that effect. The method that determines whether each
guess is valid is <code>userNumberBean.validateNumberRange</code>.</p>
<div class="paragraph">
<p><a id="GJDPW"></a><a id="running-the-guessnumber-cdi-example"></a></p>
<div class="sect2">
<h3 id="_running_the_guessnumber_cdi_example">Running the guessnumber-cdi Example</h3>
<div class="paragraph">
<p>You can use either NetBeans IDE or Maven to build, package, deploy, and
run the <code>guessnumber-cdi</code> application.</p>
<div class="paragraph">
<p>The following topics are addressed here:</p>
<div class="ulist">
<p><a href="#GJDPS">To Build, Package, and Deploy the guessnumber-cdi Example
Using NetBeans IDE</a></p>
<p><a href="#GJDPR">To Build, Package, and Deploy the guessnumber-cdi Example
Using Maven</a></p>
<p><a href="#GJDQB">To Run the guessnumber Example</a></p>
<div class="paragraph">
<p><a id="GJDPS"></a><a id="to-build-package-and-deploy-the-guessnumber-cdi-example-using-netbeans-ide"></a></p>
<div class="sect3">
<h4 id="_to_build_package_and_deploy_the_guessnumber_cdi_example_using_netbeans_ide">To Build, Package, and Deploy the guessnumber-cdi Example Using NetBeans IDE</h4>
<div class="olist arabic">
<ol class="arabic">
<p>Make sure that GlassFish Server has been started (see
<a href="usingexamples002.html#BNADI">Starting and Stopping GlassFish
Server</a>).</p>
<p>From the <strong>File</strong> menu, choose <strong>Open Project</strong>.</p>
<p>In the <strong>Open Project</strong> dialog box, navigate to:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">tut-install/examples/cdi</code></pre>
<p>Select the <code>guessnumber-cdi</code> folder.</p>
<p>Click <strong>Open Project</strong>.</p>
<p>In the <strong>Projects</strong> tab, right-click the <code>guessnumber-cdi</code> project and
select <strong>Build</strong>.</p>
<div class="paragraph">
<p>This command builds and packages the application into a WAR file,
<code>guessnumber-cdi.war</code>, located in the <code>target</code> directory, and then
deploys it to GlassFish Server.</p>
<div class="paragraph">
<p><a id="GJDPR"></a><a id="to-build-package-and-deploy-the-guessnumber-cdi-example-using-maven"></a></p>
<div class="sect3">
<h4 id="_to_build_package_and_deploy_the_guessnumber_cdi_example_using_maven">To Build, Package, and Deploy the guessnumber-cdi Example Using Maven</h4>
<div class="olist arabic">
<ol class="arabic">
<p>Make sure that GlassFish Server has been started (see
<a href="usingexamples002.html#BNADI">Starting and Stopping GlassFish
Server</a>).</p>
<p>In a terminal window, change to the following directory:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">tut-install/examples/cdi/guessnumber-cdi/</code></pre>
<p>Enter the following command to deploy the application:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">mvn install</code></pre>
<div class="paragraph">
<p>This command builds and packages the application into a WAR file,
<code>guessnumber-cdi.war</code>, located in the <code>target</code> directory, and then
deploys it to GlassFish Server.</p>
<div class="paragraph">
<p><a id="GJDQB"></a><a id="to-run-the-guessnumber-example"></a></p>
<div class="sect3">
<h4 id="_to_run_the_guessnumber_example">To Run the guessnumber Example</h4>
<div class="olist arabic">
<ol class="arabic">
<p>In a web browser, enter the following URL:</p>
<div class="listingblock">
<div class="content">
<pre class="prettyprint highlight"><code class="language-oac_no_warn" data-lang="oac_no_warn">http://localhost:8080/guessnumber-cdi</code></pre>
<div class="paragraph">
<p>The <strong>Guess My Number</strong> page opens.</p>
<p>On the <strong>Guess My Number</strong> page, enter a number in the <strong>Number</strong> field and
click <strong>Guess</strong>.</p>
<div class="paragraph">
<p>The minimum and maximum values are modified, along with the remaining
number of guesses.</p>
<p>Keep guessing numbers until you get the right answer or run out of
guesses.</p>
<div class="paragraph">
<p>If you get the right answer or run out of guesses, the input field and
<strong>Guess</strong> button are grayed out.</p>
<p>Click <strong>Reset</strong> to play the game again with a new random number.</p>
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