xmlutil.java

对eclipse gef进行封装,可以生成图形化编辑器

/*******************************************************************************
 * $Header: /cvsroot/EOS6/work_dir/niegy/com.primeton.studio.gef.ui/src/com/primeton/studio/gef/ui/util/XmlUtil.java,v 1.2 2006/12/30 02:45:04 niegy Exp $
 * $Revision: 1.2 $
 * $Date: 2006/12/30 02:45:04 $
 *
 *==============================================================================
 *
 * Copyright (c) 2001-2006 Primeton Technologies, Ltd.
 * All rights reserved. 
 * 
 * Created on 2006-10-30
 *******************************************************************************/


package com.primeton.studio.gef.ui.util;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.CharArrayReader;
import java.io.CharArrayWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.Properties;
import java.util.Vector;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;

import org.eclipse.core.resources.IFile;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;

import com.sun.org.apache.xml.internal.serializer.OutputPropertiesFactory;
import com.sun.org.apache.xml.internal.serializer.Serializer;
import com.sun.org.apache.xml.internal.serializer.SerializerFactory;
import com.sun.org.apache.xpath.internal.XPathAPI;

/**
 * TODO此处填写 class 信息
 *
 * @author niegy (mailto:[e-mail])
 */
/*
 * 修改历史
 * $Log: XmlUtil.java,v $
 * Revision 1.2  2006/12/30 02:45:04  niegy
 * 重构代码
 *
 * Revision 1.1  2006/11/17 03:15:13  niegy
 * create
 * 
 */
public class XmlUtil {
    private static final String DEFAULT_XML_ENCODING = "UTF-8";

    //space符号
    private static char[] chars = { 'n', (char) 9, (char) 10, (char) 13, ' ' };

    /** 实例化XML Document
     * 
     * @return Document
     */
    public static Document newDocument() {
        return getXMLBuilder().newDocument();
    }

    /** 给指定父节点创建子节点(父节点是Document的情况)
     * 
     * @param Document parent 
     * @param String name 
     * @return Element
     */
    public static Element createElement(Document document, String name) {
        Element element = document.createElement(name);
        document.appendChild(element);
        return element;
    }

    /** 给指定父节点创建子节点(父节点是Element的情况)
     * 
     * @param Element parent 
     * @param String name 
     * @return Element
     */
    public static Element createElement(Element parent, String name) {
        return createField(parent, name, null);
    }

    /** 给指定父节点创建子节点并赋值
     * 
     * @param NodeElement parent 
     * @param String name 
     * @param String value 
     * @return Element
     */
    public static Element createField(Element parent, String name, String value) {
        Document document = parent.getOwnerDocument();
        if (document == null)
            return null;
        //Creates an element of the type specified
        Element element = document.createElement(name);
        //Adds the node newChild to the end of the list of children of this node
        parent.appendChild(element);

        if (value != null && !value.equals("")) {
            //Creates a Text node given the specified string
            Text text = document.createTextNode(value);
            element.appendChild(text);
        }
        return element;
    }

    /** 取得指定元素的指定节点的值
     * 
     * @param Element element
     * @param String name 
     * @return String 
     */
    public static String getFieldValue(Element element, String name) {
        if (element == null || name == null || name.equals(""))
            return null;

        //get the NodeList that contains all children of this node
        NodeList children = element.getChildNodes();
        for (int i = 0; i < children.getLength(); i++) {
            Node field = children.item(i);
            if (field instanceof Element && field.getNodeName().equals(name)) {
                return getTextValue(field);
            }
        }
        return null;
    }

    /** 取得指定子元素
     * 
     * @param Element element 
     * @param String fieldName 
     * @return Element 
     */
    public static Element getChild(Element element, String fieldName) {
        if (element == null || fieldName == null || fieldName.equals(""))
            return null;
        NodeList children = element.getChildNodes();
        for (int i = 0; i < children.getLength(); i++) {
            Node child = children.item(i);
            if (child instanceof Element
                    && child.getNodeName().equals(fieldName)) {
                return (Element) child;
            }
        }
        return null;
    }

    /** 取得节点的TextValue
     * 
     * @param NodeElement node 
     * @return String 
     */
    public static String getTextValue(Node node) {
        NodeList children = node.getChildNodes();
        if (children == null)
            return ""; //$NON-NLS-1$
        for (int i = 0; i < children.getLength(); i++) {
            Node child = children.item(i);
            if (child.getNodeType() == Node.TEXT_NODE) {
                String value = ((org.w3c.dom.Text) child).getNodeValue();
                if (value != null)
                    value = value.trim();
                return value;
            }
        }
        return ""; //$NON-NLS-1$
    }

    /** 设置元素属性
     * 
     * @param Element element
     * @param String name
     * @param String value
     */
    public static void setAttribute(Element element, String name, String value) {
        if (element == null || value == null || value.equals(""))
            return;
        element.setAttribute(name, value.trim());
    }

    /**
     * convert the node to string, 默认不进行格式化
     * @param node a node
     * @return the result string
     */
    public final static String node2String(Node node) {
        return node2String(node, false);
    }
    
    /**
     * convert the node to string<br>
     * 格式化输出将改变node的结构
     * @param node a node
     * @param isFormat true:格式化输出
     * @return the result string
     */
    public final static String node2String(Node node, boolean isFormat) {
        return node2String(node, isFormat, true);
    }
    
    /** 将XML节点序列化成字符串
     * 
     * @param node 
     * @param isFormat
     * @param hasHead
     * @return
     */
    public final static String node2String(Node node, boolean isFormat,
            boolean hasHead) {
        if (node == null)
            return null;

        //The node is a Document
        if (node.getNodeType() == Node.DOCUMENT_NODE)
            node = ((Document) node).getDocumentElement();

        CharArrayWriter writer = new CharArrayWriter();
        try {
            Properties prop = OutputPropertiesFactory
                    .getDefaultMethodProperties("xml");

            prop.setProperty("encoding", DEFAULT_XML_ENCODING);

            Serializer serializer = SerializerFactory.getSerializer(prop);

            if (isFormat) {
                prop.setProperty(OutputKeys.INDENT, "yes");
                prop.setProperty(OutputPropertiesFactory.S_KEY_INDENT_AMOUNT, "4");
                XmlUtil.removeSpace(node);
            } else {
                prop.setProperty(OutputKeys.INDENT, "no");
            }
            serializer.setOutputFormat(prop);

            serializer.setWriter(writer);

            //串行化输出结果
            serializer.asDOMSerializer().serialize(node);

            String str = new String(writer.toCharArray());
            if (hasHead) {
                if (!str.startsWith("<?xml")) {
                    str = ("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n")
                            .concat(str);
                }
                return str;
            } else {
                if (!str.startsWith("<?xml")) {
                    return str;
                }
                int op = str.indexOf("?>");
                str = str.substring(op + "?>".length()).trim();
                if (str.startsWith("\n")) {
                    str = str.substring(1);
                }
            }

        } catch (Exception e) {
//            Logger.error(DSBCore.getDefault(), e);
        }
        return node.toString();
    }

    /**
     * find node array from node use by the given XPath
     * @param node a node
     * @param xql XPath
     * @return the node array, if not find return null
     * @throws XmlUtilException
     */
    public final static NodeList findNodes(Node node, String xql)
            throws XmlUtilException {
        if ((xql == null) || (xql.length() == 0)) {
            throw new XmlUtilException("xql == null");
        }

        if (node == null) {
            throw new XmlUtilException("Node == null");
        }
        try {
            if (node.getNodeType() != Node.DOCUMENT_NODE)
                xql = processXql(xql);
            return XPathAPI.selectNodeList(node, xql);

            //          NodeList findNode = XPathAPI.selectNodeList(node, xql);
            //          if(findNode == null || findNode.getLength() == 0){
            //              if(!"bendpoints/bendpoint".equals(xql)){
            //                  String root = null;
            //                  if(node.getNodeType() == Node.DOCUMENT_NODE){
            //                      root = ((Document)node).getDocumentElement().toString();
            //                  }else{
            //                      root = node.toString();
            //                  }
            //                  Logger.debug(CorePlugin.getDefault(), "findNodes not find : [" + xql + "]\n" + root);
            //              }
            //          }
            //          return findNode;

        } catch (Exception te) {
            throw new XmlUtilException(te.getMessage());
        }
    }

    /**
     * find a single node from node use by the given XPath
     * @param node a node
     * @param xql XPath
     * @return the node, if not find return null
     * @throws XmlUtilException
     */
    public final static Node findNode(Node node, String xql)
            throws XmlUtilException {
        if ((xql == null) || (xql.length() == 0)) {
            throw new XmlUtilException("xql == null");
        }

        if (node == null) {
            throw new XmlUtilException("Source node == null");
        }
        try {
            if (node.getNodeType() != Node.DOCUMENT_NODE)
                xql = processXql(xql);
            return XPathAPI.selectSingleNode(node, xql);
            //          Node findNode = XPathAPI.selectSingleNode(node, xql);
            //          if(findNode == null && !"bendpoints/bendpoint".equals(xql)){
            //              String root = null;
            //              if(node.getNodeType() == Node.DOCUMENT_NODE){
            //                  root = ((Document)node).getDocumentElement().toString();
            //              }else{
            //                  root = node.toString();
            //              }
            //              Logger.debug(CorePlugin.getDefault(), "findNode not find : [" + xql + "]\n" + root);
            //          }
            //          return findNode;
        } catch (Exception te) {
            throw new XmlUtilException(te.getMessage());
        }
    }
    
    private final static String processXql(String xql) {
        if (xql.length() > 1 && xql.charAt(0) == '/')
            xql = ".".concat(xql);
        return xql;
    }
    

    
    /**
     * 从Element的下一级中获得指定名称子Element的Value, 如果重名, 得到第一个
     * @param Element superEle
     * @param String subName
     * @return Element
     */
    public final static String subElementValue(Element superEle, String subName) {
        Element element = subElement(superEle, subName);
        if (element == null)
            return null;
        else {
            return getElementValue(element);
        }
    }
    
    /**
     * 从Element的下一级中获得指定名称的子Element
     * 如果重名, 得到第一个
     * @param Element superEle
     * @param String subName
     * @return Element
     */
    public final static Element subElement(Element superEle, String subName) {
        NodeList list = superEle.getChildNodes();
        if (list == null)
            return null;
        for (int i = 0; i < list.getLength(); i++) {
            Node node = list.item(i);
            if (node.getNodeType() == Node.ELEMENT_NODE) {
                if (node.getNodeName().equals(subName)) {
                    return (Element) node;
                }
            }
        }
        return null;