loader constraint violation: Problem while using xerces 2.9.1

I reproduced the same exception with Grails 1.2-M4 on Mac OS X with the Drools plugin version 0.3

user@host> grails create-app test
user@host> cd test
user@host> grails install-plugin drools
...
...
Executing drools-0.3 plugin post-install script ...
Plugin drools-0.3 installed

user@host> grails run-app
...
...
java.lang.LinkageError: loader constraint violation: loader (instance of <bootloader> previously initiated loading for a different type with name "org/xml/sax/SAXParseException"
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
at java.lang.Class.getDeclaredMethods(Class.java:1791)
at java.security.AccessController.doPrivileged(Native Method)
at org.codehaus.groovy.util.LazyReference.getLocked(LazyReference.java:33)
at org.codehaus.groovy.util.LazyReference.get(LazyReference.java:20)
at grails.util.PluginBuildSettings.getPluginInfos(PluginBuildSettings.groovy:95)
at grails.util.PluginBuildSettings$getPluginInfos.call(Unknown Source)
at _PackagePlugins_groovy$_run_closure2.doCall(_PackagePlugins_groovy:70)
at _GrailsPackage_groovy$_run_closure2.doCall(_GrailsPackage_groovy:76)
at RunApp$_run_closure1.doCall(RunApp.groovy:28)
at gant.Gant$_dispatch_closure4.doCall(Gant.groovy:324)
at gant.Gant$_dispatch_closure6.doCall(Gant.groovy:334)
at gant.Gant$_dispatch_closure6.doCall(Gant.groovy)
at gant.Gant.withBuildListeners(Gant.groovy:344)
at gant.Gant.this$2$withBuildListeners(Gant.groovy)
at gant.Gant$this$2$withBuildListeners.callCurrent(Unknown Source)
at gant.Gant.dispatch(Gant.groovy:334)
at gant.Gant.this$2$dispatch(Gant.groovy)
at gant.Gant.invokeMethod(Gant.groovy)
at gant.Gant.processTargets(Gant.groovy:495)
at gant.Gant.processTargets(Gant.groovy:480)
Error executing script RunApp: loader constraint violation: loader (instance of <bootloader> previously initiated loading for a different type with name "org/xml/sax/SAXParseException"

does this help? http://old.nabble.com/xerces-2.9.1-%2B-grails-td25085644.html

Or maybe this one: http://old.nabble.com/first-grails-app---Linkage-errors,-java-6-td21882311.html

Hi, I did some investigation and it seems that it is similar problem to http://jira.codehaus.org/browse/GROOVY-2303 .
I removed xml-apis dependency for xalan and xerces from my pom definition and it's seams that it help.

I have to remove other dependency now...

I think it will become a big problem eventually... If you have any idea how to solve it or you can solve it in more general way that would be great.

I am also experiencing this problem. It seems related to the closed issue http://jira.codehaus.org/browse/GRAILS-5337.

I have not seen the problem under Maven, only with Ivy. At this point I have been unable to prevent Ivy from loading xml-api, and my only solution has been to place an empty xml-api.jar in the ivy repository.

I would really appreciate an update on this issue. Thanks,

– Harlan

I had this issue when resolving some axis2/rampart dependencies in order to consume webservices. Xerces and xml-apis were subdependencies of the axis2/rampart jars in the maven repository. My current solution to prevent xerces and xml-apis is to use the Grails Ivy excludes command.

build ("axis2/rampart dependencies") {
excludes "xercesImpl", "xmlParserAPIs", "xml-apis";
}

Thanks Brian, that did the job as a work around. I had tried something similar earlier but had the wrong Ivy syntax (not so familiar with it), so thanks for the example.

The issues remain rather inconvenient though. When using a Maven pom for dependency management (pom=true in grails config) and running Maven operations everything works, but running a Grails command with the same configuration results in an error. So the work around comes down to maintaining the pom for dependencies (so I can use Maven as part of our standard build) and maintaining the ivy dependency management (so Intellij with work and a developer has the option of running standard Grails commands).

I have this issue in grail 1.2.0 version.

I have this issue in 1.3.0RC1 with the GWT plugin.

Similar problem occurs when using org.codehaus.groovy.modules.http-builder (http://groovy.codehaus.org/modules/http-builder/home.html)

The following fixed the problem:
test('org.codehaus.groovy.modules.http-builder:http-builder:0.5.1')

I encountered a similar problem and after following a note on GRAILS-5337, was able to resolve it by deleting my Ivy cache (~/.ivy2/cache). Hope that helps.

Delete the .ivy2/cache!

Experiencing this problem when performing run-app on a Grails 1.3.7 app with Apache POI 3.8. Excluding xmlbeans from the dependencies seemed to work:

dependencies {
compile('org.apache.poi:poi-ooxml:3.8-beta3')

}

HI Bryan,
How did you solve this problem. I am having the same issue and I am not able to solve it. Please help

I excluded xml-apis in my pom.xml and now the war file is getting created successfully.
But i'm getting java.lang.NoClassDefFoundError: org/w3c/dom/ElementTraversal during the runtime.
If i include xml-api.jar inside the WEB-INF/lib directory after the creation of war file, the error disappeared.
Unfortunately, i can't do this manually. I'm using Grails 1.3.7.
(Even including xml-apis with "runtime" dependency in pom.xml doesn't help )
Any work around for this is highly appreciated.

Although this still "could" happen in Grails 2 we have reduced the risk greatly by automatically excluding xml-apis and any XML jars from dependency resolution, hence reducing the priority

Just a note on one jar you might want to add to the exclusions, xom
That one was causing the same issues that this one was so just thought i'd mention it.

This still affects me, and when using exclusions I get runtime errors.

I am using grails 2.1

I believe that much of what is reported here is due to GRAILS-9352.