hot deploying simple application in jetty

Question

I am working with jetty hightide vesion 7 currently as a stand alone server. I have a simple web project with a couple of jsp's and backing classes that I am currently deploying in an unexploded war to the JETTY_HOME/webapps directory.

Currently, jetty easily picks up any static jsp/html changes. If I understand correctly, I can configure my app so that jetty will pick up any class changes without restarting the server? I currently have in my jetty-web.xml:

<?xml version="1.0"  encoding="ISO-8859-1"?>
<!DOCTYPE Configure PUBLIC "-//Mort Bay Consulting//DTD Configure//EN" "http://www.eclipse.org/jetty/configure.dtd"&gt;

<!--
    This is the jetty specific web application configuration file. When
    starting a Web Application, the WEB-INF/web-jetty.xml file is looked
    for and if found, treated as a
    org.eclipse.jetty.server.server.xml.XmlConfiguration file and is
    applied to the org.eclipse.jetty.servlet.WebApplicationContext objet
-->

<Configure class="org.eclipse.jetty.webapp.WebAppContext">
<Call class="org.eclipse.jetty.util.log.Log" name="debug">
    <Arg>executing jetty-web.xml</Arg>
</Call>
<Set name="contextPath">/SimpleDynamicProject</Set>

</Configure>

I also have created a SimpleDynamicProject.xml and put it in JETTY_HOME/contexts. This file contains:

<?xml version="1.0"  encoding="ISO-8859-1"?>
<!DOCTYPE Configure PUBLIC "-//Mort Bay Consulting//DTD Configure//EN" "http://www.eclipse.org/jetty/configure.dtd"&gt;

<!--
    This is the jetty specific web application configuration file. When
    starting a Web Application, the WEB-INF/web-jetty.xml file is looked
    for and if found, treated as a
    org.eclipse.jetty.server.server.xml.XmlConfiguration file and is
    applied to the org.eclipse.jetty.servlet.WebApplicationContext objet
-->

<Configure class="org.eclipse.jetty.webapp.WebAppContext">

<Set name="contextPath">/SimpleDynamicProject</Set>
<Set name="resourceBase"><SystemProperty name="jetty.home" default="."/>/webapps/SimpleDynamicProject</Set>
</Configure>

I am also not sure how to correctly start Jetty in debug mode which I read was also needed. I have tried starting the server with:

java -Xdebug -jar start.jar OPTIONS=Server,jsp

and

java -Ddebug -jar start.jar OPTIONS=Server,jsp

This is the first time I've used jetty, but so far I really like it.

Thanks for the help.

Answer 1

You need to define a ContextDeployer with a non-zero scan interval:

<Call name="addLifeCycle">
  <Arg>
    <New class="org.mortbay.jetty.deployer.ContextDeployer">
      <Set name="contexts"><Ref id="Contexts"/></Set>
      <Set name="configurationDir"><SystemProperty name="jetty.home" default="."/>/contexts</Set>
      <Set name="scanInterval">1</Set>
    </New>
  </Arg>
</Call>

Regarding debugging, I guess that what you have in mind is to connect a remote debugger using JPDA. For this, you'll need to set the -agentlib:jdwp option¹:

-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5005

The configure your IDE debugger to connect on the specified port.

_{¹ if the target VM is 5.0 or newer, -agentlib:jdwp is preferable over the -Xdebug and -Xrunjdwp options which are still supported though.}

Answer 2

If you want to use jetty maven plugin

   <plugin>
        <groupId>org.mortbay.jetty</groupId>
        <artifactId>maven-jetty-plugin</artifactId>
        <version>6.1.25</version>
        <configuration>
            <scanIntervalSeconds>10</scanIntervalSeconds>
            <requestLog implementation="org.mortbay.jetty.NCSARequestLog">
                <!--
                          This doesn't do anything for Jetty, but is a workaround for a
                          Maven bug that prevents the requestLog from being set.
                      -->
                <append>true</append>
            </requestLog>
            <webApp>${basedir}/out/war/Spring2_5_6_war.war</webApp>
        </configuration>
    </plugin>