使用Itext 把Html转换成pdf 总是出错

org.xhtmlrenderer.util.XRRuntimeException: Can't load the XML resource (using TRaX transformer). java.io.IOException: Stream closed
at org.xhtmlrenderer.resource.XMLResource$XMLResourceBuilder.createXMLResource(XMLResource.java:191)
at org.xhtmlrenderer.resource.XMLResource.load(XMLResource.java:71)
at org.xhtmlrenderer.swing.NaiveUserAgent.getXMLResource(NaiveUserAgent.java:211)
at org.xhtmlrenderer.pdf.ITextRenderer.loadDocument(ITextRenderer.java:134)
at org.xhtmlrenderer.pdf.ITextRenderer.setDocument(ITextRenderer.java:138)
at com.htmltopdf.HttpToPdf.HttpTestPdf(HttpToPdf.java:34)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
Caused by: javax.xml.transform.TransformerException: java.io.IOException: Stream closed
at org.apache.xalan.transformer.TransformerIdentityImpl.transform(TransformerIdentityImpl.java:506)
at org.xhtmlrenderer.resource.XMLResource$XMLResourceBuilder.createXMLResource(XMLResource.java:189)
... 28 more
Caused by: java.io.IOException: Stream closed
at java.io.BufferedInputStream.getInIfOpen(Unknown Source)
at java.io.BufferedInputStream.fill(Unknown Source)
at java.io.BufferedInputStream.read(Unknown Source)
at org.apache.xerces.impl.XMLEntityManager$RewindableInputStream.readAndBuffer(Unknown Source)
at org.apache.xerces.impl.XMLEntityManager.setupCurrentEntity(Unknown Source)
at org.apache.xerces.impl.XMLVersionDetector.determineDocVersion(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at org.apache.xalan.transformer.TransformerIdentityImpl.transform(TransformerIdentityImpl.java:485)
... 29 more