REVERT TO CONSOLE

I was struggling to add HtmlUnit to Grails to do some testing when I came upon this.

The solution was to remove the HtmlUnit included jar, xml-apis-1.3.04.

The error looked like this:

loader constraint violation: loader (instance of <bootloader>) previously initiated loading for a different type with name "org/w3c/dom/NamedNodeMap"
java.lang.LinkageError: loader constraint violation: loader (instance of ) previously initiated loading for a different type with name "org/w3c/dom/NamedNodeMap"
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
at java.lang.Class.getMethod0(Class.java:2670)
at java.lang.Class.getMethod(Class.java:1603)
at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.isDom3Present(ContextFactory.java:301)
at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.getE4xImplementationFactory(ContextFactory.java:328)
at net.sourceforge.htmlunit.corejs.javascript.Context.getE4xImplementationFactory(Context.java:2175)
at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.initStandardObjects(ScriptRuntime.java:222)
at net.sourceforge.htmlunit.corejs.javascript.Context.initStandardObjects(Context.java:1069)
at net.sourceforge.htmlunit.corejs.javascript.Context.initStandardObjects(Context.java:1036)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.init(JavaScriptEngine.java:157)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.access$000(JavaScriptEngine.java:68)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$1.run(JavaScriptEngine.java:130)
at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:515)
at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:507)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.initialize(JavaScriptEngine.java:141)
at com.gargoylesoftware.htmlunit.WebClient.initialize(WebClient.java:1107)
at com.gargoylesoftware.htmlunit.WebWindowImpl.setEnclosedPage(WebWindowImpl.java:99)
at com.gargoylesoftware.htmlunit.html.HTMLParser.parse(HTMLParser.java:268)
at com.gargoylesoftware.htmlunit.DefaultPageCreator.createHtmlPage(DefaultPageCreator.java:127)
at com.gargoylesoftware.htmlunit.DefaultPageCreator.createPage(DefaultPageCreator.java:101)
at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseInto(WebClient.java:442)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:329)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:386)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:371)
at UIUnitTests.setUp(UIUnitTests.groovy:12)
at _GrailsTest_groovy$_run_closure4.doCall(_GrailsTest_groovy:202)
at _GrailsTest_groovy$_run_closure2.doCall(_GrailsTest_groovy:146)
at _GrailsTest_groovy$_run_closure1_closure19.doCall(_GrailsTest_groovy:112)
at _GrailsTest_groovy$_run_closure1.doCall(_GrailsTest_groovy:95)
at TestApp$_run_closure1.doCall(TestApp:66)
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)