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In order to use the Convention plugin, you first need to add the JAR file to the WEB-INF/lib directory of your application or include the dependency in your project's Maven POM file.

<dependency>
  <groupId>org.apache.struts</groupId>
  <artifactId>struts2-convention-plugin</artifactId>
  <version>2.1.6</version>
</dependency>

Converting a Codebehind based application to Convention

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