java - XMLStreamException：试图输出第二个根，StaXparser

Question

writer.writeStartElement(startElement.getName().getLocalPart());

//当我用一个线程在独立机器上运行时，它工作正常，但是当我在服务器上用多个线程运行多个作业时，它给了我以下错误

writer.writeStartElement(startElement.getName().getLocalPart());

javax.xml.stream.XMLStreamException: Trying to output second root, <element>

ERROR [STDERR] (JBossQuartzScheduler_Worker-4) javax.xml.stream.XMLStreamException:
 Trying to output second root, <handset>
ERROR [STDERR] (JBossQuartzScheduler_Worker-4)  at com.ctc.wstx.sw.BaseStreamWriter.throwOutputError(BaseStreamWriter.java:1473)
ERROR [STDERR] (JBossQuartzScheduler_Worker-4)  at com.ctc.wstx.sw.BaseStreamWriter.throwOutputError(BaseStreamWriter.java:1480)
ERROR [STDERR] (JBossQuartzScheduler_Worker-4)  at com.ctc.wstx.sw.BaseStreamWriter.reportNwfStructure(BaseStreamWriter.java:1508)
ERROR [STDERR] (JBossQuartzScheduler_Worker-4)  at com.ctc.wstx.sw.BaseNsStreamWriter.checkStartElement(BaseNsStreamWriter.java:444)
ERROR [STDERR] (JBossQuartzScheduler_Worker-4)  at com.ctc.wstx.sw.BaseNsStreamWriter.writeStartElement(BaseNsStreamWriter.java:292)