HTTP ERROR 500 {msg=XSLT transformation error for xslt/main_ead.xsl, trace=java.io.IOException: XSLT transformation error for xslt/main_ead.xsl at com.infolytics.kopac.solr.XSLTResponseWriter.write(XSLTResponseWriter.java:212) at org.apache.solr.response.QueryResponseWriterUtil.writeQueryResponse(QueryResponseWriterUtil.java:63) at org.apache.solr.servlet.HttpSolrCall.writeResponse(HttpSolrCall.java:1004) at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:600) at org.apache.solr.servlet.SolrDispatchFilter.dispatch(SolrDispatchFilter.java:241) at org.apache.solr.servlet.SolrDispatchFilter.lambda$doFilterRetry$0(SolrDispatchFilter.java:198) at org.apache.solr.servlet.ServletUtils.traceHttpRequestExecution2(ServletUtils.java:227) at org.apache.solr.servlet.ServletUtils.rateLimitRequest(ServletUtils.java:197) at org.apache.solr.servlet.SolrDispatchFilter.doFilterRetry(SolrDispatchFilter.java:192) at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:181) at javax.servlet.http.HttpFilter.doFilter(HttpFilter.java:97) at org.eclipse.jetty.servlet.FilterHolder.doFilter(FilterHolder.java:210) at org.eclipse.jetty.servlet.ServletHandler$Chain.doFilter(ServletHandler.java:1635) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:527) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:131) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:598) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:223) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1580) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:221) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1384) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:176) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:484) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1553) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:174) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1306) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:129) at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:149) at org.eclipse.jetty.server.handler.InetAccessHandler.handle(InetAccessHandler.java:228) at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:141) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122) at org.eclipse.jetty.rewrite.handler.RewriteHandler.handle(RewriteHandler.java:301) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122) at org.eclipse.jetty.server.handler.gzip.GzipHandler.handle(GzipHandler.java:822) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:122) at org.eclipse.jetty.server.Server.handle(Server.java:563) at org.eclipse.jetty.server.HttpChannel$RequestDispatchable.dispatch(HttpChannel.java:1598) at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:753) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:501) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:287) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:314) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:100) at org.eclipse.jetty.io.SelectableChannelEndPoint$1.run(SelectableChannelEndPoint.java:53) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.runTask(AdaptiveExecutionStrategy.java:421) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.consumeTask(AdaptiveExecutionStrategy.java:390) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.tryProduce(AdaptiveExecutionStrategy.java:277) at org.eclipse.jetty.util.thread.strategy.AdaptiveExecutionStrategy.run(AdaptiveExecutionStrategy.java:199) at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:411) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:969) at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.doRunJob(QueuedThreadPool.java:1194) at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:1149) at java.base/java.lang.Thread.run(Unknown Source) Caused by: net.sf.saxon.trans.XPathException: A sequence of more than one item is not allowed as the second argument of fn:concat() (@authfilenumber="DE-1", @authfilenumber="DE-NoIsil30101") at net.sf.saxon.expr.Expression.typeError(Expression.java:1473) at net.sf.saxon.expr.SingletonAtomizer.evaluateItem(SingletonAtomizer.java:246) at net.sf.saxon.expr.SingletonAtomizer.evaluateItem(SingletonAtomizer.java:33) at net.sf.saxon.functions.Concat$1.evaluateAsString(Concat.java:93) at net.sf.saxon.expr.instruct.SimpleNodeConstructor.processLeavingTail(SimpleNodeConstructor.java:226) at net.sf.saxon.expr.instruct.Block.processLeavingTail(Block.java:752) at net.sf.saxon.expr.instruct.Instruction.process(Instruction.java:142) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:352) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:298) at net.sf.saxon.expr.instruct.Block.processLeavingTail(Block.java:752) at net.sf.saxon.expr.instruct.Instruction.process(Instruction.java:142) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:352) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:298) at net.sf.saxon.expr.instruct.Block.processLeavingTail(Block.java:752) at net.sf.saxon.expr.instruct.Instruction.process(Instruction.java:142) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:352) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:298) at net.sf.saxon.expr.instruct.Block.processLeavingTail(Block.java:752) at net.sf.saxon.expr.instruct.Instruction.process(Instruction.java:142) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:352) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:298) at net.sf.saxon.expr.instruct.Block.processLeavingTail(Block.java:752) at net.sf.saxon.expr.instruct.Instruction.process(Instruction.java:142) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:352) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:298) at net.sf.saxon.expr.instruct.Block.processLeavingTail(Block.java:752) at net.sf.saxon.expr.instruct.Instruction.process(Instruction.java:142) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:352) at net.sf.saxon.expr.instruct.ElementCreator.processLeavingTail(ElementCreator.java:298) at net.sf.saxon.expr.LetExpression.processLeavingTail(LetExpression.java:746) at net.sf.saxon.expr.instruct.Block.processLeavingTail(Block.java:752) at net.sf.saxon.expr.instruct.NamedTemplate.expand(NamedTemplate.java:264) at net.sf.saxon.expr.instruct.CallTemplate$CallTemplatePackage.processLeavingTail(CallTemplate.java:549) at net.sf.saxon.trans.Mode.applyTemplates(Mode.java:478) at net.sf.saxon.trans.XsltController.applyTemplates(XsltController.java:661) at net.sf.saxon.s9api.AbstractXsltTransformer.applyTemplatesToSource(AbstractXsltTransformer.java:360) at net.sf.saxon.s9api.XsltTransformer.transform(XsltTransformer.java:349) at net.sf.saxon.jaxp.TransformerImpl.transform(TransformerImpl.java:74) at com.infolytics.kopac.solr.XSLTResponseWriter.write(XSLTResponseWriter.java:210) ... 51 more , code=500}