/**
 * Copyright (c) 2002 sinosoft  Co. Ltd.
 * All right reserved.
 */
//*******************************************************************
// Java  XMLPATHTool:
//	Name        :
//      Test content:
//	Comment	    :
//	Date        :
//********************************************************************
//1.得到document 对象;2.传入xpath表达式3.返回结点集
package com.sinosoft.utility;

import com.sinosoft.print.func.XMLPrintTagName;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.xpath.XPathAPI;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

/**
 * XPathAPI应用类
 * <p>
 * Title: Life Information System
 * </p>
 * <p>
 * Description:
 * </p>
 * <p>
 * Copyright: Copyright (c) 2002
 * </p>
 * <p>
 * Company:
 * </p>
 * 
 * @author Kevin
 * @version 1.0
 */
public class XMLPathTool {
    private static final Logger logger = LoggerFactory.getLogger(XMLPathTool.class);

	/* 对应的Dom树 */
	private Document sourceDom;

	/* 对应的文件名 */
	private String fileName;



	/**
	 * 从一个StringReader对象中产生一个Document
	 * 
	 * @param in
	 *            InputStream 输入流
	 */
	public XMLPathTool(InputStream in) {
		this.fileName = "";
        try
        {
            DocumentBuilderFactory dfactory = DocumentBuilderFactory.
                                              newInstance();
			// 拒绝 DOCTYPE
			dfactory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
			// 禁止外部实体
			dfactory.setFeature("http://xml.org/sax/features/external-general-entities", false);
			dfactory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
            dfactory.setNamespaceAware(true);
			dfactory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
			dfactory.setFeature("http://xml.org/sax/features/external-general-entities", false);
			dfactory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
			dfactory.setXIncludeAware(false);
			dfactory.setExpandEntityReferences(false);
            InputStreamReader strInStream = new InputStreamReader(in, "UTF-8");
            sourceDom = dfactory.newDocumentBuilder().parse(new InputSource(strInStream));

        }
        catch (Exception ex)
        {
            logger.error("程序执行异常",ex);
        }
	}

	/**
	 * 获取文档的document对象。
	 * 
	 * @param fileName
	 *            String 输入的文件名。
	 * @return Document 文件名对应的document对象。
	 * @throws ParserConfigurationException
	 * @throws SAXException
	 * @throws IOException
	 */
	private static Document getDocument(String fileName)
			throws ParserConfigurationException, SAXException, IOException {
		try (FileInputStream fis = new FileInputStream(fileName)) {
			InputSource in = new InputSource(fis);
			DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
			// 拒绝 DOCTYPE
			dfactory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
			// 禁止外部实体
			dfactory.setFeature("http://xml.org/sax/features/external-general-entities", false);
			dfactory.setFeature("http://xml.org/sax/features/external-parameter-entities", false);
			dfactory.setNamespaceAware(true);
			Document doc = dfactory.newDocumentBuilder().parse(in);
			return doc;
		}
	}

	/**
	 * 分析xpath串。
	 * 
	 * @param xpathString
	 *            要进行分析的xpath表达式。
	 * @return 结果集。
	 */
	public Node parseX(String xpathString) {
		try {
			if (sourceDom == null) {
				sourceDom = getDocument(fileName);
			}
//			xpathString = XMLPrintTagName.changeROWToR(xpathString);
			return XPathAPI.selectSingleNode(sourceDom.getDocumentElement(),
					xpathString);

		} catch (Exception ex) {
			logger.error("程序执行异常",ex);
			return null;
		}
	}

	/**
	 * 分析xpath串。
	 * 
	 * @param xpathString
	 *            要进行分析的xpath表达式。
	 * @return 结果集。
	 */
	public NodeList parseN(String xpathString) {
		try {
			if (sourceDom == null) {
				sourceDom = getDocument(fileName);
			}
			xpathString = XMLPrintTagName.changeROWToR(xpathString);
			return XPathAPI.selectNodeList(sourceDom.getDocumentElement(),
					xpathString);

		} catch (Exception ex) {
			logger.error("程序执行异常",ex);
			return null;
		}
	}
}