xmlutil.java

本代码是一个权限管理系统源代码

package com.seavision.PermissionManage.common;

/**
 * 
 * @author  xutao.huang 
 * 
 * @version  1.0
 */
import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Hashtable;

import javax.servlet.ServletContext;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.FactoryConfigurationError;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Templates;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.TransformerFactoryConfigurationError;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

/**
 * @author av
 * XML Utilities
 */
public class XMLUtil {

  private static final String WEBKEY = XMLUtil.class.getName();
  private ServletContext context;

  private XMLUtil(ServletContext context)
  {
	this.context = context;
  }

  // Hashtable is syncronized
  private Hashtable templatesCache = new Hashtable();

  /**
   * creates a transformer for a xsl stylesheet
   * @param xslUri the uri of the xslt stylesheet, e.g. "/WEB-INF/mystyle.xsl"
   * @param xslCache cache the transformer
   * @return 转换器
   */
  public synchronized Transformer getTransformer
  (
	  String xslUri,
	  boolean xslCache)
  {
	try
	{
	  Templates templates = null;
	  if (xslCache)
		templates = (Templates) templatesCache.get(xslUri);
	  if (templates == null)
	  {
		TransformerFactory tf = TransformerFactory.newInstance();
		URL url = context.getResource(xslUri);
		if (url == null)
		  throw new IllegalArgumentException("stylesheet \"" + xslUri + "\" not found");

		templates = tf.newTemplates(new StreamSource(url.toExternalForm()));
		if (xslCache)
		  templatesCache.put(xslUri, templates);
	  }

	  return templates.newTransformer();
	}
	catch (TransformerConfigurationException e)
	{
	  e.printStackTrace();
	  return null;
	}
	catch (MalformedURLException e)
	{
	  e.printStackTrace();
	  return null;
	}
  }

  /**
   * creates a transformer for a xsl stylesheet
   * @param context for resource lookup and stylesheet caching
   * @param xslUri the uri of the xslt stylesheet, e.g. "/WEB-INF/mystyle.xsl"
   * @param xslCache cache the transformer
   * @return 转换器
   */
  public static Transformer getTransformer(ServletContext context, String xslUri, boolean xslCache)
  {
	return instance(context).getTransformer(xslUri, xslCache);
  }

  public static DocumentBuilder getParser()
  {
	try
	{
	  DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
	  dbf.setValidating(false);
	  dbf.setExpandEntityReferences(true);
	  return dbf.newDocumentBuilder();
	}
	catch (FactoryConfigurationError e)
	{
	  e.printStackTrace();
	  return null;
	}
	catch (ParserConfigurationException e)
	{
	  e.printStackTrace();
	  return null;

	}
  }

  public static Document createDocument()
  {
	try
	{
	  return getParser().newDocument();
	}
	catch (FactoryConfigurationError e)
	{
	  e.printStackTrace();
	  return null;

	}
  }

  public static void print(Node node, Writer out)
  {
	try
	{
	  TransformerFactory tf = TransformerFactory.newInstance();
	  Source src = new DOMSource(node);
	  Result dest = new StreamResult(out);
	  tf.newTransformer().transform(src, dest);
	}
	catch (TransformerConfigurationException e)
	{
	  e.printStackTrace();
	}
	catch (TransformerFactoryConfigurationError e)
	{

	}
	catch (TransformerException e)
	{
	  e.printStackTrace();
	}
  }

  public static XMLUtil instance(ServletContext context)
  {
	XMLUtil service = (XMLUtil) context.getAttribute(WEBKEY);
	if (service == null)
	{
	  service = new XMLUtil(context);
	  context.setAttribute(WEBKEY, service);
	}
	return service;
  }

  /**
   * The Document. node itself may be a Document node in which case
   * @param node node.getOwnerDocument() will return null
   * @return 文档对象
   */
  public static Document getDocument(Node node)
  {
	if (node.getNodeType() == Node.DOCUMENT_NODE)
	  return (Document) node;

	return node.getOwnerDocument();
  }

  public static Document parse(URL url)
  {
	try
	{
	  //InputSource src = new InputSource(url.openStream());
	  InputSource src = new InputSource(url.toExternalForm());
	  return getParser().parse(src);
	}
	catch (IOException e)
	{
	  e.printStackTrace();
	  return null;

	}
	catch (SAXException e)
	{
	  e.printStackTrace();
	  return null;
	}
  }

  public static Transformer getTransformer(String path)
  {
	try
	{
	  TransformerFactory tf = TransformerFactory.newInstance();
	  Templates templates = null;
	  URL url = new URL(path);

	  if (url == null)
		throw new IllegalArgumentException("stylesheet \"" + path + "\" not found");

	  templates = tf.newTemplates(new StreamSource(url.toExternalForm()));

	  return templates.newTransformer();
	}
	catch (Exception e)
	{
	  return null;
	}
  }


  public static void main(String[] args)
  {

	String xslPath = "file:///D:/JBProject/InsteadCocoon/index.xsl";

	Transformer transformer = getTransformer(xslPath);

	//获得domcment
	String xmlPath = "file:///D:/JBProject/InsteadCocoon/index.xml";

	URL xmlURL = null;
	try
	{
	  xmlURL = new URL(xmlPath);
	}
	catch (java.net.MalformedURLException e)
	{
	  e.printStackTrace();
	}

	Document document = parse(xmlURL);
	DOMSource source = new DOMSource(document);
	try
	{
	  StringWriter sw = new StringWriter();
	  StreamResult result = new StreamResult(sw);
	  transformer.transform(source, result);
	  sw.flush();
	  System.out.println(sw.toString());
	}
	catch (Exception e)
	{
	  e.printStackTrace();
	}

  }

}