带有表情符号字符的java xml解析器

以下代码用于解析xml文件.我注意到没有正确解析表情符号字符.在该示例中,输入在结尾处具有一个表情符号(http://www.iemoji.com/view/emoji/693/people/revolving-hearts),该字符在输出中加倍.这是一个已知的错误？

import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamednodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

public class XmlTest {

    public static void main(String[] args) {            
        DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();
        domFactory.setValidating(false);
        File file = new File("c:\\temp\\emoji.xml");

        try {
            DocumentBuilder builder = domFactory.newDocumentBuilder();
            Document doc = builder.parse(file);

            NodeList nodes = doc.getElementsByTagName("entry");
            Node node = nodes.item(0);
            NamednodeMap map = ((Element)node).getAttributes();

            for (int i=0; i<map.getLength(); i++) {
                Node n = map.item(i);
                System.out.println();
                System.out.println(n.getNodeValue());

                char[] chars = n.getNodeValue().tochararray();

                for (int j=0; j<chars.length; j++) {
                    System.out.print(chars[j] + ", " + (int)chars[j] + "  ");                   
                }
            }

        } catch (Exception e) {e.printstacktrace(); }
    }
}

这是输入emoji.xml：

<Attributes>
  <Map>
    <entry key="name" value="