A Jar file is Java Library. You can modularize your QWT application by splitting it into jars. This is useful to cope with complexity and to reuse common code for multiple applications.

Suppose you have an application with Java code under src/main/java. This Java code includes a package util which you want to move to a separate util.jar for reuse in other applications.

• Create a new directory util which is not under your myapp directory.
• Create a file util/pom.xml.
• Create a directory src/main/java and copy the util package into it.
• Run mvn clean install.

Now change to your application directory and:

• remove the util package
• add a dependency to util.jar to the dependencies in your application pom file:

  <dependency>
    <groupId>mygroup</groupId>
    <artifactId>util</artifactId>
    <version>1.0.0</version>
  </dependency>

• run mvn clean compile to build your application

Note that qooxdoo is just a jar for QWT, it's defined by this pom file, and applications refer to it with

<dependency>
  <groupId>org.qooxdoo.toolkit</groupId>
  <artifactId>qooxdoo</artifactId>
  <version>${toolkit.version}</version>
</dependency>