com.pactera.edg.am.metamanager.extractor.util.Dom4jReader.java Source code

Introduction

Here is the source code for com.pactera.edg.am.metamanager.extractor.util.Dom4jReader.java

Source

/*
 * Copyright 2009 by pactera.edg.am Corporation. Address:HePingLi East Street No.11
 * 5-5, BeiJing,
 * 
 * All rights reserved.
 * 
 * This software is the confidential and proprietary information of pactera.edg.am
 * Corporation ("Confidential Information"). You shall not disclose such
 * Confidential Information and shall use it only in accordance with the terms
 * of the license agreement you entered into with pactera.edg.am.
 */

package com.pactera.edg.am.metamanager.extractor.util;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PushbackInputStream;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.util.List;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.Node;
import org.dom4j.io.SAXReader;

/**
 * xpath??
 * 
 * @author user
 * @version 1.0 Date: Jul 9, 2009
 * 
 */
public class Dom4jReader {
    private final static String UTF_8 = "UTF-8";

    private final static String UTF_16LE = "UTF-16LE";

    private final static String UTF_16BE = "UTF-16BE";

    private final static String UTF8 = "UTF-8";

    private Document document;

    /**
     * 
     * @param file
     * @return
     * @throws FileNotFoundException
     */
    public boolean initDocument(File file) throws FileNotFoundException {
        InputStream input = new FileInputStream(file);
        return initDocument(input);
    }

    /**
     * 
     * @param file
     * @return
     */
    public boolean initDocument(InputStream input) {
        SAXReader xmlReader = new SAXReader();
        try {

            document = xmlReader.read(new BufferedReader(createReader(input, "UTF-8")));
            return true;
        } catch (DocumentException e) {
            e.printStackTrace();
        } finally {
        }
        return false;
    }

    private Reader createReader(InputStream input, String encoding) {
        Reader reader = null;
        if (UTF8.equals(encoding)) {
            // BOM
            try {
                final int bufSize = 1024;
                PushbackInputStream pis = new PushbackInputStream(input, bufSize);

                encoding = getBOMEncoding(pis);
                reader = new InputStreamReader(pis, encoding);
            } catch (IOException e) {
                return null;

            }
        } else {
            try {
                reader = new InputStreamReader(input, encoding);
            } catch (UnsupportedEncodingException e) {
                return null;
            }
        }

        return reader;
    }

    /**
     * 
     * ?InputStreamBOM
     * 
     * @param pis
     *            (OUT)PushbackInputStreamisBOM??BOM
     * @return BOM(?java.nio.charset.Charset)
     * @exception
     */
    public static String getBOMEncoding(PushbackInputStream pis) throws IOException {
        String encoding = UTF8;
        int[] bytes = new int[3];
        bytes[0] = pis.read();
        bytes[1] = pis.read();
        bytes[2] = pis.read();

        if (bytes[0] == 0xFE && bytes[1] == 0xFF) {
            encoding = UTF_16BE;
            pis.unread(bytes[2]);
        } else if (bytes[0] == 0xFF && bytes[1] == 0xFE) {
            encoding = UTF_16LE;
            pis.unread(bytes[2]);
        } else if (bytes[0] == 0xEF && bytes[1] == 0xBB && bytes[2] == 0xBF) {
            encoding = UTF_8;
        } else {
            for (int i = bytes.length - 1; i >= 0; i--) {
                pis.unread(bytes[i]);
            }
        }

        return encoding;
    }

    public Document getDocument() {
        return document;
    }

    public List selectNodes(String expr) {
        return document.selectNodes(expr);
    }

    public Node selectSignleNode(String expr) {
        return document.selectSingleNode(expr);
    }

    public String getElementText(Element element) {
        return element.getTextTrim();
    }

    public void close() {
        //      document.clearContent();
        document = null;
    }
}