struts2 - AnnotationActionValidatorManager - Caught exception while loading file java/lang/Object-validation.xml

Question

Struts version of our application is 2.3.8. Getting following exception after every post back to the server. Application is deployed on to WebSphere server. We don't have any validation xml in the project.

ERROR com.opensymphony.xwork2.validator.AnnotationActionValidatorManager - Caught exception while loading file java/lang/Object-validation.xml

java.lang.NullPointerException at com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.loadFile(AnnotationActionValidatorManager.java:391) at        com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.buildClassValidatorConfigs(AnnotationActionValidatorManager.java:279) at 
com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.buildValidatorConfigs(AnnotationActionValidatorManager.java:371) at 
com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.buildValidatorConfigs(AnnotationActionValidatorManager.java:350) at 
com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.getValidators(AnnotationActionValidatorManager.java:102) at 
com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.validate(AnnotationActionValidatorManager.java:141) at 
com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.validate(AnnotationActionValidatorManager.java:133) at 
com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.validate(AnnotationActionValidatorManager.java:128) at 
com.opensymphony.xwork2.validator.ValidationInterceptor.doBeforeInvocation(ValidationInterceptor.java:222)

Answer 1

There seems to be a bug since Struts2 2.3.4 version. You can refer the JIRA. This bug has been fixed in 2.3.7 version. I would recommend you to verify that all your Struts2 libraries are properly updated and deployed with the correct version. Please try upgrading your Struts2 to higher version. The difference i see is that exception accurs with AnnotationActionValidatorManager in your case, where as in the bug list. it is DefaultActionValidatorManager on which loadFile() method is invoked