hot deploy in embedded jetty

Question

I have a Spring Roo project and I use mvn jetty:run to run my app. The only problem is changes to the *.java classes do not hot deploy, while changes to *.jspx hot deploy fine.

So how can I configure mvn jetty to hotdeploy for java classes?

Sil

Answer 1

You need to set the scanIntervalSeconds to a value greater than 0 to enable it:

scanIntervalSeconds - The interval in seconds to scan the webapp for changes and restart the context if necessary. Ignored if reload is enabled. Disabled by default. Default value is: 0.

So the configuration might looks like this:

<plugin>
  <groupId>org.mortbay.jetty</groupId>
  <artifactId>maven-jetty-plugin</artifactId>
  <version>6.1.22</version>
  <configuration>
    <scanIntervalSeconds>1</scanIntervalSeconds>
  </configuration>
</plugin>

Once enabled, the jetty maven plugin will scan the directory defined in classDirecory (which points to ${project.build.outputDirectory} by default i.e. target/classes) for changes.

You then just need to have your IDE compile classes in target/classes (or to run mvn compile) and Jetty will restart the context upon changes on Java classes.

Arequipa

There are 404 errors while Jetty redeploys the classes. Any suggestion how to avoid them? Also see this question: #23343743 – Diphtheria

Unfortunately redeployment with zero downtime requires a lot of effort in the Java world :( Edit: Will try this: rafaelsteil.com/zero-downtime-deploy-script-for-jetty – Diphtheria