title: Solr dataimporter.functions.formatDate get current date
body: <p>I´m using solr 3.2 version.
  I need to get the current date in this format: yyyyMMdd and then use that result in a delta query </p>
  
  <p>I´ve tried using this wiki <a href="http://wiki.apache.org/solr/DataImportHandler#A_VariableResolver" rel="nofollow">http://wiki.apache.org/solr/DataImportHandler#A_VariableResolver</a></p>
  
  <pre><code>${dataimporter.functions.formatDate('NOW', yyyyMMdd)}
  </code></pre>
  
  <p>But I get this exception:
  Throwable occurred: java.lang.NullPointerException
      at org.apache.solr.handler.dataimport.EvaluatorBag$4.evaluate(EvaluatorBag.java:146)
      at org.apache.solr.handler.dataimport.EvaluatorBag$5.get(EvaluatorBag.java:222)
      at org.apache.solr.handler.dataimport.EvaluatorBag$5.get(EvaluatorBag.java:209)
      at org.apache.solr.handler.dataimport.VariableResolverImpl.resolve(VariableResolverImpl.java:113)
      at org.apache.solr.handler.dataimport.TemplateString.fillTokens(TemplateString.java:81)
      at org.apache.solr.handler.dataimport.TemplateString.replaceTokens(TemplateString.java:75)
      at org.apache.solr.handler.dataimport.VariableResolverImpl.replaceTokens(VariableResolverImpl.java:96)
      at org.apache.solr.handler.dataimport.ContextImpl.replaceTokens(ContextImpl.java:256)
      at org.apache.solr.handler.dataimport.SqlEntityProcessor.nextModifiedRowKey(SqlEntityProcessor.java:84)
      at org.apache.solr.handler.dataimport.EntityProcessorWrapper.nextModifiedRowKey(EntityProcessorWrapper.java:262)
      at org.apache.solr.handler.dataimport.DocBuilder.collectDelta(DocBuilder.java:884)
      at org.apache.solr.handler.dataimport.DocBuilder.doDelta(DocBuilder.java:284)
      at org.apache.solr.handler.dataimport.DocBuilder.execute(DocBuilder.java:178)
      at org.apache.solr.handler.dataimport.DataImporter.doDeltaImport(DataImporter.java:374)
      at org.apache.solr.handler.dataimport.DataImporter.runCmd(DataImporter.java:413)
      at org.apache.solr.handler.dataimport.DataImporter$1.run(DataImporter.java:392)</p>