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<chapter id="gettingstarted">

   <title>Getting started with Weld</title>

   <para>
      Weld comes with two starter example applications, in addition to more specialized examples. The first,
      <literal>weld-numberguess</literal>, is a web (war) example containing only non-transactional managed beans.
      This example can be run on a wide range of servers, including JBoss AS, GlassFish, Apache Tomcat, Jetty, Google
      App Engine, and any compliant Java EE 6 container. The second example, <literal>weld-translator</literal>, is
      an enterprise (ear) example that contains session beans. This example must be run on JBoss AS 6.0, Glassfish 3.0 
      or any compliant Java EE 6 container.
   </para>
   
   <para>
      Both examples use JSF 2.0 as the web framework and, as such, can be found in the <literal>examples/jsf</literal> 
      directory of the Weld distribution.
   </para>

   <section id="prerequisites">
      <title>Prerequisites</title>

      <para>
         To run the examples with the provided build scripts, you'll need the following:
      </para>
   
      <itemizedlist>
         <listitem>
            <para>the latest release of Weld, which contains the examples</para>
         </listitem>
         <listitem>
            <para>Ant 1.7.0, to build and deploy the examples</para>
         </listitem>
         <listitem>
            <para>a supported runtime environment (minimum versions shown)</para>
            <itemizedlist>
               <listitem>
                  <para>JBoss AS 6.0.0,</para>
               </listitem>
               <listitem>
                  <para>GlassFish 3.0,</para>
               </listitem>
               <listitem>
                  <para>Apache Tomcat 6.0.x (war example only), or</para>
               </listitem>
               <listitem>
                  <para>Jetty 6.1.x (war example only)</para>
               </listitem>
            </itemizedlist>
         </listitem>
         <listitem>
            <para>(optionally) Maven 2.x, to run the examples in an embedded servlet container</para>
         </listitem>
      </itemizedlist>
   
      <note>
         <para>
            You'll need a full install of Ant 1.7.0. Some linux distributions only supply a partial installation of Ant
            which cause the build to fail. If you encounter problems, verify that ant-nodeps.jar is on the classpath.
         </para>
      </note>
   
      <para>
         In the next few sections, you'll be using the Ant command (<literal>ant</literal>) to invoke the Ant build script 
         in each example to compile, assemble and deploy the example to JBoss AS and, for the war example, Apache Tomcat. 
         You can also deploy the generated artifact (war or ear) to any other container that supports Java EE 6, such as 
         GlassFish 3.
      </para>
   
      <para>
         If you have Maven installed, you can use the Maven command (<literal>mvn</literal>) to compile and assemble the 
         standalone artifact (war or ear) and, for the war example, run it in an embedded container.
      </para>
      
      <para>The sections below cover the steps for deploying with both Ant and Maven in detail. Let's start with JBoss AS.</para>

   </section>
   
   <section id="jbossas">
      <title>Deploying to JBoss AS</title>

      <para>
         To deploy the examples to JBoss AS, you'll need <ulink url="http://jboss.org/jbossas/">JBoss AS
         6.0.0</ulink> or above. If a release of the JBoss AS 6.0 line isn't yet available, you can download a
         <ulink url="http://hudson.jboss.org/hudson/view/JBoss%20AS/job/JBoss-AS-6.0.x/">nightly snapshot</ulink>.
         The reason JBoss AS 6.0.0 or above is required is because it's the first release that has both CDI and
         Bean Validation support built-in, making it close enough to Java EE 6 to run the examples. The good news is
         that there are no additional modifications you have to make to the server. It's ready to go!
      </para>
   
      <para>
         After you have downloaded JBoss AS, extract it. (We recommended renaming the folder to include the
         <literal>as</literal> qualifier so it's clear that it's the application server). You can move the extracted
         folder anywhere you like. Wherever it lays to rest, that's what we'll call the JBoss AS installation
         directory, or <literal>JBOSS_HOME</literal>.
      </para>
      
      <programlisting><![CDATA[$> unzip jboss-6.0.*.zip
$> mv jboss-6.0.*/ jboss-as-6.0]]></programlisting>

      <para>
         In order for the build scripts to know where to deploy the example, you have to tell them where to find your
         JBoss AS installation (i.e., <literal>JBOSS_HOME</literal>). Create a new file named <literal>local.build.properties</literal> 
         in the examples directory of the Weld distribution and assign the path of your JBoss AS installation to the 
         property key <literal>jboss.home</literal>, as follows:
      </para>

      <programlisting><![CDATA[jboss.home=/path/to/jboss-as-6.0]]></programlisting>

      <para>
         You're now ready to deploy your first example!
      </para>

      <para>
         Switch to the <literal>examples/jsf/numberguess</literal> directory and execute the Ant 
         <literal>deploy</literal> target:
      </para>

     <programlisting><![CDATA[$> cd examples/jsf/numberguess
$> ant deploy]]></programlisting> 

      <para>
         If you haven't already, start JBoss AS. You can either start JBoss AS from a Linux shell:
      </para>

      <programlisting><![CDATA[$> cd /path/to/jboss-as-6.0
$> ./bin/run.sh]]></programlisting> 
      
      <para>
         a Windows command window:
      </para>

      <programlisting><![CDATA[$> cd c:\path\to\jboss-as-6.0\bin
$> run]]></programlisting> 

      <para>
         or you can start the server using an IDE, like Eclipse.
      </para>
      
      <note>
         <para>
            If you are using Eclipse, you should seriously consider installing the <ulink
            url="http://www.jboss.org/tools">JBoss Tools</ulink> add-ons, which include a wide variety of tooling for
            JSR-299 and Java EE development, as well as an enhanced JBoss AS server view.
         </para>
      </note>

      <para>
         Wait a few seconds for the application to deploy (or the application server to start) and see if you can
         determine the most efficient approach to pinpoint the random number at the local URL <ulink
         url="http://localhost:8080/weld-numberguess">http://localhost:8080/weld-numberguess</ulink>.
      </para>

      <tip>
         <para>
            The Ant build script includes additional targets for JBoss AS to deploy and undeploy the archive in either 
            exploded or packaged format and to tidy things up.
         </para>
         <itemizedlist>
            <listitem>
               <para>
                  <literal>ant restart</literal> - deploy the example in exploded format to JBoss AS
               </para>
            </listitem>
            <listitem>
               <para>
                  <literal>ant explode</literal> - update an exploded example, without restarting the deployment
               </para>
            </listitem>
            <listitem>
               <para>
                  <literal>ant deploy</literal> - deploy the example in compressed jar format to JBoss AS
               </para>
            </listitem>
            <listitem>
               <para>
                  <literal>ant undeploy</literal> - remove the example from JBoss AS
               </para>
            </listitem>
            <listitem>
               <para>
                  <literal>ant clean</literal> - clean the example
               </para>
            </listitem>
         </itemizedlist>
      </tip>

      <para>
         The second starter example, <literal>weld-translator</literal>, will translate your text into Latin. (Well,
         not really, but the stub is there for you to implement, at least. Good luck!) To try it out, switch to the
         translator example directory and execute the deploy target:
      </para>
   
      <programlisting><![CDATA[$> cd examples/jsf/translator
$> ant deploy]]></programlisting> 

      <note>
         <para>
            The translator uses session beans, which are packaged in an EJB module within an ear. Java EE 6 will allow
            session beans to be deployed in war modules, but that's a topic for a later chapter.
         </para>
      </note>

      <para>
         Again, wait a few seconds for the application to deploy (if you're really bored, read the log messages), and 
         visit <ulink url="http://localhost:8080/weld-translator">http://localhost:8080/weld-translator</ulink> to begin
         pseudo-translating.
      </para>
   
   </section>

   <section id="glassfish">
      <title>Deploying to GlassFish</title>

      <para>
         Deploying to GlassFish should be easy, right? After all, it's the Java EE 6 reference implementation. Since
         it's the Java EE 6 reference implementation, that means it also bundles the JSR-299 reference implementation,
         Weld! So yes, it's very easy.
      </para>

      <para>
         To deploy the examples to GlassFish, you'll need the final <ulink
         url="https://glassfish.dev.java.net/">GlassFish V3</ulink> release (the preview release won't do). If the final
         release isn't yet available, you can download a <ulink
         url="http://download.java.net/glassfish/v3/promoted/">promoted build</ulink> in the meantime. Select the b69
         preview release or above that ends in either <literal>-unix.sh</literal> or <literal>-windows.exe</literal> 
         depending on your platform. After the download is complete, execute the installer. On Linux/Unix, you'll need 
         to first make the script executable.
      </para>

      <programlisting><![CDATA[$> chmod 755 glassfish-v3-b69-unix.sh
$> ./glassfish-v3-b69-unix.sh]]></programlisting> 

      <para>
         On Windows you can just click on the executable. Follow the instructions in the installer. It will create a
         single domain named <literal>domain1</literal>. You'll use that domain to deploy the example. We recommend that
         you choose <literal>7070</literal> as the main HTTP port to avoid conflicts with a running instance of JBoss AS 
         (or Apache Tomcat).
      </para>
   
      <para>
         If you've deployed either of the starter examples, <literal>weld-numberguess</literal> or
         <literal>weld-translator</literal>, to JBoss AS, then you already have the deployable artifact you need.
         If not, switch to either of the two directories and build it.
      </para>

      <programlisting><![CDATA[$> cd examples/jsf/numberguess (or examples/jsf/translator)
$> ant package]]></programlisting> 

      <para>
         The deployable archive for the <literal>weld-numberguess</literal>, named <literal>weld-numberguess.war</literal>, 
         ends up in the example's <literal>target</literal> directory. The archive for the <literal>weld-translator</literal> 
         example, named <literal>weld-translator.ear</literal>, ends up in the example's <literal>ear/target</literal> directory. 
         All you need to do now is deploy them to GlassFish.
      </para>

      <para>
         You deploy applications to GlassFish using the <ulink url="http://localhost:4848">GlassFish Admin
         Console</ulink>. To get the Admin Console running, you need to start a GlassFish domain, in our case
         <literal>domain1</literal>. Switch to the <literal>bin</literal> folder in the directory where you 
         installed GlassFish and execute the following command:
      </para>

      <programlisting><![CDATA[$> asadmin start-domain domain1]]></programlisting> 

      <para>
         After a few seconds you can visit the Admin Console in the browser at the URL <ulink
         url="http://localhost:4848">http://localhost:4848</ulink>. In the tree on the left-hand
         side of the page, click on "Applications", then click on the "Deploy..." button under
         the heading "Applications" and select the deployable artifact for either of the two examples.
         The deployer should recognize that you have selected a Java EE artifact and allow you to
         start it. You can see the examples running at either <ulink
         url="http://localhost:7070/weld-numberguess">http://localhost:7070/weld-numberguess</ulink> or <ulink
         url="http://localhost:7070/weld-translator">http://localhost:7070/weld-translator</ulink>,
         depending on which example you deployed.
      </para>

      <para>
         The reason the same artifact can be deployed to both JBoss AS and GlassFish, without any modifications, is
         because all of the features being used are part of the standard platform. And what a capable platform it has
         become!
      </para>

   </section>
   
   <section id="tomcat">
      <title>Deploying to Apache Tomcat</title>

      <para>
         Servlet containers are not required to support Java EE services like CDI. However, you can use CDI in a 
         servlet container like Tomcat by embedding a standalone CDI implementation such as Weld.</para>
         
      <para>
         Weld comes with a servlet listener which bootstraps the CDI environment, registers the <literal>BeanManager</literal> 
         in JNDI and provides injection into servlets. Basically, it emulates some of the work done by the Java EE 
         container. (But you don't get enterprise features such as session beans and container-managed transactions.)
      </para>

      <para>
         Let's give the Weld servlet extension a spin on Apache Tomcat. First, you'll need to download Tomcat 6.0.18 or 
         later from <ulink url="http://tomcat.apache.org/download-60.cgi">tomcat.apache.org</ulink> and extract it.
      </para>

      <programlisting><![CDATA[$> unzip apache-tomcat-6.0.18.zip]]></programlisting> 

      <para>
         You have two choices for how you can deploy the application to Tomcat. You can deploy it by pushing the
         artifact to the hot deploy directory using Ant or you can deploy to the server across HTTP using a Maven
         plugin. The Ant approach doesn't require that you have Maven installed, so we'll start there. If you want to
         use Maven, you can just skip ahead.
      </para>

      <section id="tomcat-ant">
         <title>Deploying with Ant</title>

         <para>
            In order for Ant to push the artifact to the Tomcat hot deploy directory, it needs to know where the Tomcat
            installation is located. Again, we need to set a property in the <literal>local.build.properties</literal> 
            file in the examples directory of the Weld distribution. If you haven't yet created this file, do so now. 
            Then assign the path of your Tomcat installation to the property key <literal>tomcat.home</literal>.
         </para>
   
         <programlisting><![CDATA[tomcat.home=/path/to/apache-tomcat-6]]></programlisting> 
   
         <para>
            Now you're ready to deploy the numberguess example to Tomcat!
         </para>
   
         <para>
            Change to the <literal>examples/jsf/numberguess</literal> directory again and run the Ant <literal>deploy</literal> 
            target for Tomcat:
         </para>
   
         <programlisting><![CDATA[$> cd examples/jsf/numberguess
$> ant tomcat.deploy]]></programlisting> 
         
         <tip>
            <para>
               The Ant build script includes additional targets for Tomcat to deploy and undeploy the archive in either
               exploded or packaged format. They are the same target names used for JBoss AS, prefixed with "tomcat.".
            </para>
            <itemizedlist>
               <listitem>
                  <para>
                     <literal>ant tomcat.restart</literal> - deploy the example in exploded format to Tomcat
                  </para>
               </listitem>
               <listitem>
                  <para>
                     <literal>ant tomcat.explode</literal> - update an exploded example, without restarting the deployment
                  </para>
               </listitem>
               <listitem>
                  <para>
                     <literal>ant tomcat.deploy</literal> - deploy the example in compressed jar format to Tomcat
                  </para>
               </listitem>
               <listitem>
                  <para>
                     <literal>ant tomcat.undeploy</literal> - remove the example from Tomcat
                  </para>
               </listitem>
            </itemizedlist>
         </tip>
   
         <para>
            If you haven't already, start Tomcat. You can either start Tomcat from a Linux shell:
         </para>
   
         <programlisting><![CDATA[$> cd /path/to/apache-tomcat-6
$> ./bin/start.sh]]></programlisting> 
   
         <para>
            a Windows command window:
         </para>
   
         <programlisting><![CDATA[$> cd c:\path\to\apache-tomcat-6\bin
$> start]]></programlisting> 
   
         <para>
            or you can start the server using an IDE, like Eclipse.
         </para>
   
         <para>
            Wait a few seconds for the application to deploy (or the application server to start) and see if you can figure
            out the most efficient approach to pinpoint the random number at the local URL
            <ulink url="http://localhost:8080/weld-numberguess">http://localhost:8080/weld-numberguess</ulink>!
         </para>

      </section>
      
      <section id="tomcat-maven">
         <title>Deploying with Maven</title>

         <para>
            You can also deploy the application to Tomcat using Maven. This section is a bit more advanced, so skip it
            unless you're itching to use Maven natively. Of course, you'll first need to make sure that you have Maven
            installed on your path, similar to how you setup Ant.
         </para>

         <para>
            The Maven plugin communicates with Tomcat over HTTP, so it doesn't care where you have installed Tomcat.
            However, the plugin configuration assumes you are running Tomcat in its default configuration, with a hostname
            of localhost and port <literal>8080</literal>. The <literal>readme.txt</literal> file in the example directory 
            has information about how to modify the Maven settings to accommodate a different setup.
         </para>

         <para>
            To allow Maven to communicate with Tomcat over HTTP, edit the <literal>conf/tomcat-users.xml</literal> file in 
            your Tomcat installation and add the following line:
         </para>

         <programlisting role="XML"><![CDATA[<user username="admin" password="" roles="manager"/>]]></programlisting> 

         <para>
            Restart Tomcat. You can now deploy the application to Tomcat with Maven using this command:
         </para>

         <programlisting><![CDATA[$> mvn compile war:exploded tomcat:exploded -Ptomcat]]></programlisting> 

         <para>
            Once the application is deployed, you can redeploy it using this command:
         </para>

         <programlisting><![CDATA[$> mvn tomcat:redeploy -Ptomcat]]></programlisting> 

         <para>
            The <literal>-Ptomcat</literal> argument activates the <literal>tomcat</literal> profile defined in the Maven POM 
            (<literal>pom.xml</literal>). Among other things, this profile activates the Tomcat plugin.
         </para>

         <para>
            Rather than shipping the container off to a standalone Tomcat installation, you can also execute the
            application in an embedded Tomcat 6 container:
         </para>

         <programlisting><![CDATA[$> mvn war:inplace tomcat:run -Ptomcat]]></programlisting> 

         <para>
            The advantage of using the embedded server is that changes to assets in <literal>src/main/webapp</literal> take effect
            immediately. If a change to a webapp configuration file is made, the application may automatically redeploy
            (depending on the plugin configuration). If you make a change to a classpath resource, you need to execute a
            build:
         </para>

         <programlisting><![CDATA[$> mvn compile war:inplace -Ptomcat]]></programlisting> 

         <para>
            There are several other Maven goals that you can use if you are hacking on the example, which are documented in
            the example's <literal>readme.txt</literal> file.
         </para>

      </section>

   </section>

   <section id="jetty">
      <title>Deploying to Jetty</title>

      <!-- subsections? -->

      <para>
         Support for Jetty in the examples is a more recent addition. Since Jetty is traditionally used with Maven,
         there are no Ant targets. You must invoke the Maven build directly to deploy the examples to Jetty out of the
         box. Also, only the <literal>weld-numberguess</literal> example is configured for Jetty support at the time of
         writing.
      </para>

      <para>
         If you've read through the entire Tomcat section, then you're all ready to go. The Maven build parallels the
         embedded Tomcat deployment. If not, don't worry. We'll still go over everything that you need to know again
         in this section.
      </para>

      <para>
         The Maven POM (<literal>pom.xml</literal>) includes a profile named <literal>jetty</literal> that activates the 
         Maven Jetty plugin, which you can use
         to start Jetty in embedded mode and deploy the application in place. You don't need anything else installed
         except to have the Maven command (<literal>mvn</literal>) on your path. The rest will be downloaded from the 
         internet when the
         build is run.
      </para>

      <para>
         To run the <literal>weld-numberguess</literal> example on Jetty, switch to the example directory and execute
         the <literal>inplace</literal> goal of the Maven war plugin followed by the <literal>run</literal> goal of 
         the Maven Jetty plugin with the <literal>jetty</literal> profile enabled, as follows:
      </para>

      <programlisting><![CDATA[$> cd examples/jsf/numberguess
$> mvn war:inplace jetty:run -Pjetty]]></programlisting> 

      <para>
         The log output of Jetty will be shown in the console. Once Jetty reports that the application has deployed, you
         can access it at the following local URL: <ulink
         url="http://localhost:9090/weld-numberguess">http://localhost:9090/weld-numberguess</ulink>. The port is
         defined in the Maven Jetty plugin configuration within the <literal>jetty</literal> profile.
      </para>

      <para>
         Any changes to assets in <literal>src/main/webapp</literal> take effect immediately. If a change to a webapp 
         configuration file is made, the application may automatically redeploy. The redeploy behavior can be fined-tuned 
         in the plugin configuration. If you make a change to a classpath resource, you need to execute a build and the 
         <literal>inplace</literal> goal of the Maven war plugin, again with the <literal>jetty</literal> profile enabled.
      </para>

      <programlisting><![CDATA[$> mvn compile war:inplace -Pjetty]]></programlisting> 

      <para>
         The <literal>war:inplace</literal> goal copies the compiled classes and jars inside <literal>src/main/webapp</literal>, 
         under <literal>WEB-INF/classes</literal> and <literal>WEB-INF/lib</literal>, respectively, mixing source and compiled 
         files. However, the build does work around these temporary files by excluding them from the packaged war and cleaning 
         them during the Maven clean phase. 
      </para>

      <para>
         You have two options if you want to run the example on Jetty from the IDE. You can either install the
         m2eclispe[link] plugin and run the goals as described above. Your other option is to start the Jetty container
         from a Java application.
      </para>

      <para>
         First, initialize the Eclipse project:
      </para>

      <programlisting><![CDATA[$> mvn clean eclipse:clean eclipse:eclipse -Pjetty-ide]]></programlisting> 

      <para>
         Next, assemble all the necessary resources under <literal>src/main/webapp</literal>:
      </para>

      <programlisting><![CDATA[$> mvn war:inplace -Pjetty-ide]]></programlisting> 

      <para>
         Now, you are ready to run the server in Eclipse. Import the project into your Eclipse workspace using "Import
         Existing Project into Workspace. Then, find the start class in <literal>src/jetty/java</literal> and run its 
         main method as a Java Application. Jetty will launch. You can view the application at the following local URL: <ulink
         url="http://localhost:8080">http://localhost:8080</ulink>.  Pay particular attention to the port in the URL and
         the lack of a trailing context path.
      </para>

      <para>
         Now that you have gotten the starter applications deployed on the server of your choice, you probably want to
         know a little bit about how they actually work.
      </para>

   </section>

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