title: XML solr update and solr handlr java 500 error
body: <p>When I try to import my xml file (which is formatted as such):</p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; ?&gt;
  &lt;add&gt;
  &lt;doc&gt;
      &lt;field name=&quot;last_updated&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;identifier&quot;&gt;
              &lt;field name=&quot;id&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;type&quot;&gt;content&lt;/field&gt;
          &lt;/field&gt;
          &lt;field name=&quot;identifier&quot;&gt;
              &lt;field name=&quot;id&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;type&quot;&gt;content&lt;/field&gt;
          &lt;/field&gt;
          &lt;field name=&quot;journal&quot;&gt;
              &lt;field name=&quot;volume&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;country&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;content&quot;&gt;
                  &lt;field name=&quot;open_access&quot;&gt;content&lt;/field&gt;
                  &lt;field name=&quot;title&quot;&gt;content&lt;/field&gt;
                  &lt;field name=&quot;type&quot;&gt;content&lt;/field&gt;
                  &lt;field name=&quot;url&quot;&gt;content&lt;/field&gt;
              &lt;/field&gt;
              &lt;field name=&quot;issns&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;publisher&quot;&gt;content/field&gt;
              &lt;field name=&quot;language&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;title&quot;&gt;content&lt;/field&gt;
          &lt;/field&gt;
          &lt;field name=&quot;month&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;keywords&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;keywords&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;keywords&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;keywords&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;keywords&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;year&quot;&gt;content&lt;/field&gt;
          &lt;field name=&quot;subject&quot;&gt;
              &lt;field name=&quot;code&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;scheme&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;term&quot;&gt;content&lt;/field&gt;
          &lt;/field&gt;
          &lt;field name=&quot;term&quot;&gt;
              &lt;field name=&quot;affiliation&quot;&gt;content&lt;/field&gt;
              &lt;field name=&quot;name&quot;&gt;content&lt;/field&gt;
          &lt;/field&gt;
          &lt;field name=&quot;link&quot;&gt;
              &lt;field name=&quot;content_type&quot;&gt;HTML&lt;/field&gt;
              &lt;field name=&quot;type&quot;&gt;fulltext&lt;/field&gt;
              &lt;field name=&quot;url&quot;&gt;content/full&lt;/field&gt;
          &lt;/field&gt;
          &lt;field name=&quot;abstract&quot;&gt;content&lt;/field&gt;
      
      &lt;field name=&quot;admin&quot;&gt;
          &lt;field name=&quot;seal&quot;&gt;true&lt;/field&gt;
      &lt;/field&gt;
      &lt;field name=&quot;created_date&quot;&gt;content&lt;/field&gt;
      &lt;field name=&quot;id&quot;&gt;content&lt;/field&gt;
  &lt;/doc&gt;
  
  [continues]
  &lt;/add&gt;
  </code></pre>
  <p>I keep on receiving the following error when I try to post it to solr via the: <code>java -Dc=articles -jar example\exampledocs\post.jar DOAJ_1.xml</code> command.</p>
  <pre><code>SimplePostTool: WARNING: Solr returned an error #500 (Server Error) for url: http://localhost:8983/solr/articles/update
  SimplePostTool: WARNING: Response: &lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
  &lt;response&gt;
  
  &lt;lst name=&quot;responseHeader&quot;&gt;
    &lt;int name=&quot;status&quot;&gt;500&lt;/int&gt;
    &lt;int name=&quot;QTime&quot;&gt;39&lt;/int&gt;
  &lt;/lst&gt;
  &lt;lst name=&quot;error&quot;&gt;
    &lt;str name=&quot;trace&quot;&gt;java.lang.NullPointerException
          at org.apache.solr.update.processor.FieldMutatingUpdateProcessor.processAdd(FieldMutatingUpdateProcessor.java:110)
          at org.apache.solr.update.processor.UpdateRequestProcessor.processAdd(UpdateRequestProcessor.java:55)
          at org.apache.solr.update.processor.AbstractDefaultValueUpdateProcessorFactory$DefaultValueUpdateProcessor.processAdd(AbstractDefaultValueUpdateProcessorFactory.java:92)
          at org.apache.solr.handler.loader.XMLLoader.processUpdate(XMLLoader.java:261)
          at org.apache.solr.handler.loader.XMLLoader.load(XMLLoader.java:188)
          at org.apache.solr.handler.UpdateRequestHandler$1.load(UpdateRequestHandler.java:97)
          at org.apache.solr.handler.ContentStreamHandlerBase.handleRequestBody(ContentStreamHandlerBase.java:68)
          at org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:199)
          at org.apache.solr.core.SolrCore.execute(SolrCore.java:2551)
          at org.apache.solr.servlet.HttpSolrCall.execute(HttpSolrCall.java:733)
          at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:531)
          at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:395)
          at org.apache.solr.servlet.SolrDispatchFilter.doFilter(SolrDispatchFilter.java:341)
          at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1602)
          at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:540)
          at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:146)
          at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548)
          at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
          at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:257)
          at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1588)
          at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255)
          at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1345)
          at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203)
          at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:480)
          at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1557)
          at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201)
          at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1247)
          at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144)
          at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:220)
          at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:126)
          at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
          at org.eclipse.jetty.rewrite.handler.RewriteHandler.handle(RewriteHandler.java:335)
          at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
          at org.eclipse.jetty.server.Server.handle(Server.java:502)
          at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:364)
          at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:260)
          at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305)
          at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
          at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118)
          at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333)
          at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310)
          at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168)
          at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126)
          at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366)
          at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:765)
          at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:683)
          at java.base/java.lang.Thread.run(Thread.java:832)
  &lt;/str&gt;
    &lt;int name=&quot;code&quot;&gt;500&lt;/int&gt;
  &lt;/lst&gt;
  &lt;/response&gt;
  SimplePostTool: WARNING: IOException while reading response: java.io.IOException: Server returned HTTP response code: 500 for URL: http://localhost:8983/solr/articles/update
  1 files indexed.
  COMMITting Solr index changes to http://localhost:8983/solr/articles/update...
  Time spent: 0:00:28.239
  </code></pre>
  <p>I hope that I have provided enough information, if not, please let me know and I would be happy to provide more details. I would really appreciate it if anyone could try and help me figuring this out. Thanks in advance.</p>