JDK 10＆＃x2B;内部Xerces错误

Question

我相信我在JDK 10+中发现了一个明显的错误。我已经向Oracle报告了它，由于我没有任何回应，所以我在这里记录了，也许社区可以确认。此错误在Apache Xerces中不存在，因此这就是解决方法。 document.normalizedocument（）返回命名属性属性的JDK 9.0.4的不一致结果。

最终，错误是名为nodemapimpl.clonemap（arrayList列表）更改了实现，并且Domnormalizer称其为依赖于所传递的列表作为方法参数，而不是返回值。如果使用返回值，则不会有错误。

com.sun.org.apache.xerces.internal.dom.domnormalizer：885

    // clone content of the attributes
    attributes.cloneMap(fAttributeList);

注意此方法依赖于fattributelist在CloneMap中填充并忽略返回值。

如果我们查看JDK 9名为nodemapimpl.clonemap

/**
 * NON-DOM: copy content of this map into the specified ArrayList
 *
 * @param list   ArrayList to copy information into.
 * @return A copy of this node named map
 */
protected ArrayList cloneMap(ArrayList list) {
    if (list == null) {
        list = new ArrayList(5);
    }
    list.clear();
    if (nodes != null) {
        final int size = nodes.size();
        for (int i = 0; i < size; ++i) {
            list.add(nodes.get(i));
        }
    }
    return list;
}

现在，我们会查看JDK 10

/**
 * NON-DOM: copy content of this map into the specified ArrayList
 *
 * @param list   ArrayList to copy information into.
 * @return A copy of this node named map
 */
protected List<Node> cloneMap(List<Node> list) {
    if (nodes != null) {
        list = new ArrayList<>(nodes);
    }
    return list;
}

JDK 9清除了通过jdk 10“ News”的参数，该参数在调用Domnoralizer中丢失其参考的参数，没有任何内容。没有任何内容克隆的意思没有对这些属性进行进一步处理。

我认为这是一个明显的错误。谷歌搜索没有打击，除了有人说它值得怀疑。 https://bugs.openjdk.java.java.net/browse/browse/jdk-8233750

这是我在JDK 9下运行的测试，然后是10个观察输出差异。

package test;

import java.io.StringWriter;
import org.w3c.dom.Attr;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.bootstrap.DOMImplementationRegistry;
import org.w3c.dom.ls.DOMImplementationLS;
import org.w3c.dom.ls.LSInput;
import org.w3c.dom.ls.LSOutput;
import org.w3c.dom.ls.LSParser;
import org.w3c.dom.ls.LSSerializer;

public class main {

  public static void main(final String[] args) {
    try
    {
      final DOMImplementationRegistry registry = DOMImplementationRegistry.newInstance();
      final DOMImplementationLS impl = (DOMImplementationLS) registry.getDOMImplementation("LS");
      final LSParser builder = impl.createLSParser(DOMImplementationLS.MODE_SYNCHRONOUS, null);
      final LSInput input = impl.createLSInput();
      input.setStringData("<xml/>");

      final Document document = builder.parse(input);
      final Element root = document.getDocumentElement();

      // Generate a single element
      final Element element = document.createElement("token");

      final Attr attr = element.getOwnerDocument().createAttributeNS("http://blah.xsd", "wsu");
      attr.setValue("Id");
      element.setAttributeNodeNS(attr);

      final Attr attr2 = element.getOwnerDocument().createAttributeNS("http://blah2.xsd", "wsu2");
      element.setAttributeNodeNS(attr2);

      final Attr attr3 = element.getOwnerDocument().createAttribute("aa");
      element.setAttributeNodeNS(attr3);

      final Attr attr4 = element.getOwnerDocument().createAttribute("zz");
      element.setAttributeNodeNS(attr4);

      final Attr attr5 = element.getOwnerDocument().createAttribute("tt");
      element.setAttributeNodeNS(attr5);

      root.appendChild(element);

      for ( int i = 0; i < element.getAttributes().getLength(); i++ )
      {
        System.out.println("PRE normalise attr " + element.getAttributes().item(i).getNodeName());
      }
      System.out.println("PRE normalise " + prettyPrintFromDocument(document));
      document.normalizeDocument();
      for ( int i = 0; i < element.getAttributes().getLength(); i++ )
      {
        System.out.println("POST normalise attr " + element.getAttributes().item(i).getNodeName());
      }
      System.out.println("POST normalise " + prettyPrintFromDocument(document));
    }
    catch ( final Exception ex )
    {
      ex.printStackTrace();
    }
}

/**
 * Pretty prints a DOM document to a String.
 *
 * @param message the DOM document to serialise.
 * @return a string representation of the DOM message parameter.
 */
private static String prettyPrintFromDocument(final Document message) {
  try {
    final DOMImplementationRegistry registry = DOMImplementationRegistry.newInstance();

    final DOMImplementationLS impl = (DOMImplementationLS) registry.getDOMImplementation("LS");

    final LSSerializer writer = impl.createLSSerializer();
    final LSOutput output = impl.createLSOutput();

    final StringWriter sw = new StringWriter();

    output.setEncoding("UTF-8");
    output.setCharacterStream(sw);

    try {
      writer.getDomConfig().setParameter("format-pretty-print", Boolean.TRUE);
    } catch (final Exception ignore) {
    }

    writer.write(message, output);

    return sw.toString();
  } catch (final RuntimeException e) {
    throw e;
  } catch (final Exception e) {
    throw new RuntimeException(e);
  }
}
}