Struts 2 Jars Conflict

Question

My struts 2 tile application was working fine. But after adding the struts2-jquery-plugin library jar, I am getting the following error:

"SEVERE: Exception starting filter struts2 Unable to load configuration. - [unknown location]"

My libraries structure is:

• antlr-2.7.6
• commons-beanutils-1.7.0
• commons-collections-3.1
• commons-digester-1.7
• commons-fileupload-1.2.1
• commons-io-1.3.2
• commons-lang-2.3
• commons-logging-1.1
• freemarker-2.3.13
• hsqldb
• jta-1.1
• log4j-1.2.15
• ognl-2.6.11
• slf4j-api-1.5.8
• slf4j-log4j12-1.5.8
• struts2-convention-plugin-2.1.6
• struts2-core-2.1.6
• struts2-jquery-plugin-3.5.1
• struts2-tiles-plugin-2.1.6
• tiles-api-2.1.2
• tiles-compat-2.1.2
• tiles-core-2.1.2
• tiles-jsp-2.1.2
• tiles-servlet-2.1.2
• xwork-2.1.2

I am unable to find the jars/classes which are getting conflict.

And I want to know what is the best way to overcome such conflict.

Thanks!

Answer 1

The conflicts are coming from using a version of the jQuery plugin that doesn't work with the version of S2 you're using. 3.5.1 of the s2 jQuery plugin requires S2 2.3.8, as its POM shows (in struts2-jquery, the plugin's parent project).

You cannot arbitrarily mix-and-match versions of libraries; you must respect dependencies unless you are certain they're compatible. It's why we have tools like Maven.

One way to highlight possible conflicts is to use mvn dependency:tree and see where there are multiple versions of the same library.