Changes required

• Replace org.apache.struts2.config.Namespace with org.apache.struts2.convention.annotation.Namespace
• Replace org.apache.struts2.config.Results with org.apache.struts2.convention.annotation.Results
• Replace org.apache.struts2.config.Result with org.apache.struts2.convention.annotation.Result
• Update @Result uses to use result name instead of Class<Result>
• Update @Result uses to use location instead of value attribute
• Update web.xml and remove Codebehind params from filter
• Update CamelCase action results and references to match Convention. For example:

When REST plugin is used

Add these constants to struts.xml