[WW-4331] ConventionUnknownHandler throws null

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.3.15.2
• Fix Version/s: 2.3.20
• Component/s: Plugin - Convention

Environment

Tomcat 7.0.50
Java 1.7.0_40

• Assignee: Lukasz Lenart
• Reporter: justin miller
• Created: 24/Apr/14 20:06
• Updated: 13/Jan/15 11:58
• Resolved: 28/Jul/14 19:17

Description

ConventionUnknownHandler's handleUnknownActionMethod() always throws null which causes a NullPointerException when using the Rest-Plugin. This method is called due to RestActionMapper setting the default action method to "index" while the ConventionUnknownHandler creates an ActionSupport proxy expecting the "execute" method. Throwing null prevents the HandlerManager from handing off to the next UnknownHandler in the list, if one exists. This is related to issue WW-3368. Here's the abbreviated stack trace:

java.lang.NullPointerException
	org.apache.struts2.convention.ConventionUnknownHandler.handleUnknownActionMethod(ConventionUnknownHandler.java:423)
	com.opensymphony.xwork2.DefaultUnknownHandlerManager.handleUnknownMethod(DefaultUnknownHandlerManager.java:96)
	com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:437)
	com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:289)
	com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:252)
	org.apache.struts2.rest.RestActionInvocation.invoke(RestActionInvocation.java:138)

Here's the patch:

423c423
< throw null;
—
> return null;

Issue Links

• relates to: WW-4433 ConventionUnknownHandler change breaks exception handling in interceptors.