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Run/Debug java webapp without packaging/deploying it with Jetty and under Maven2


As the title mentioned, run(with maven2 command or in IDE)/debug(in IDE) java webapp without packaging the war file, installing/configuring any appserver like tomcat or deploying your code to anywhere. The practice will be "compile and run".

Why Jetty?

Jetty is a lightweight, flexible and embeddable Java servlet container. It's so flexible that it can even start servicing a webapp directly from given classpath and a web.xml file without assembling them into a standard webapp.

Step by step

Introduce several dependencies into you pom file. This is required whatsoever if you want to run/debug jetty in IDE and make sure the servlet-api, xercesImpl and java tools.jar(if you want to run JSP) are in dependency list.

Create jetty config file PROJECT_BASE_DIR/src/test/config/jetty.xml, assuming the web.xml file is already under src/main/webapp/WEB-INF directory. Feel free to change the directory and port if you want.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE Configure PUBLIC "-//Mort Bay Consulting//DTD Configure//EN"
<Configure class="org.mortbay.jetty.Server">
<Call name="addListener">
<New class="org.mortbay.http.SocketListener">
<Set name="port">
<SystemProperty name="jetty.port" default="8081" />
<Call name="addWebApplication">
Now, after injecting add dependencies into you IDE(For eclipse, run mvn eclipse:eclipse [-DdownloadSources=true] or use m2eclipse eclipse plugin), you should be able to run/debug the webapp after the code compiles. A java application with org.mortbay.jetty.Server as main class and src/test/config/jetty.xml as argument will start the webapp on port 8081.

Jetty6.x required less jar file dependencies, particularly only one jetty jar file if you don't want to run JSP, and syntax of jetty.xml file will be different. Please look at for more details.


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