有做过XSD校验XML文件的没，帮指点一下

import java.io.IOException;
import java.io.UnsupportedEncodingException;import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
import org.dom4j.util.XMLErrorHandler;
import org.xml.sax.SAXException;public class Demo { /**
 * @param args
 */
public static void main(String[] args) {
// TODO Auto-generated method stub
SAXReader reader = new SAXReader(); reader.setValidation(true);
try {
reader.setFeature("http://xml.org/sax/features/validation", true);
reader.setFeature("http://apache.org/xml/features/validation/schema", true); reader.setProperty("http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation",
                                "F:\\Manifest\\XSD\\Manifest_Declare_Export_Ship_First.xsd"); XMLErrorHandler errorHandler = new XMLErrorHandler();
reader.setErrorHandler(errorHandler); Document document = reader.read("F:\\Manifest\\CN_MT2101_1p0_420071802289020100627010905235.xml");
XMLWriter writer = new XMLWriter(OutputFormat.createPrettyPrint());
if (errorHandler.getErrors().hasContent()) {
        writer.write(errorHandler.getErrors());
} else {
        System.out.println("validate success.");
}
} catch (SAXException e) {
e.printStackTrace();
} catch (DocumentException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

}}一执行这段代码，就报以下错误
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
at org.apache.xerces.impl.dtd.models.CMStateSet.<init>(Unknown Source)
at org.apache.xerces.impl.dtd.models.CMNode.firstPos(Unknown Source)
at org.apache.xerces.impl.xs.models.XSCMUniOp.calcFirstPos(Unknown Source)
at org.apache.xerces.impl.dtd.models.CMNode.firstPos(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.calcFollowList(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.buildDFA(Unknown Source)
at org.apache.xerces.impl.xs.models.XSDFACM.<init>(Unknown Source)
at org.apache.xerces.impl.xs.models.CMBuilder.createDFACM(Unknown Source)
at org.apache.xerces.impl.xs.models.CMBuilder.getContentModel(Unknown Source)
at org.apache.xerces.impl.xs.XSComplexTypeDecl.getContentModel(Unknown Source)
at org.apache.xerces.impl.xs.XMLSchemaValidator.handleStartElement(Unknown Source)
at org.apache.xerces.impl.xs.XMLSchemaValidator.startElement(Unknown Source)
at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)网上说是虚拟机内存不足导致的，但我加大了还是报错，请问有没有人有这方面的经验。
谢谢