root/tools/routingservice/branches/wrs-2.0/src/util/IOHelper.java

/*  WRS 2.0
 *  Copyright (C) 2009 Anton Patrushev
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

package util;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.text.DecimalFormat;

import org.w3c.dom.Document;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Source;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;

import org.xml.sax.SAXException;

public class IOHelper
{

        static final String W3C_XML_SCHEMA = "http://www.w3.org/2001/XMLSchema";
        public static final DecimalFormat FORMATTER = new DecimalFormat("##########0.######");

        @SuppressWarnings("unchecked")
        public static <T> T readConfig(Class<T> docClass, String fileName)
                        throws SAXException, IOException, ParserConfigurationException,
                        JAXBException
        {
                T conf = null;

                if (validateXML(fileName))
                {
                        DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory
                                        .newInstance();
                        DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();
                        Document doc = docBuilder.parse(new File(fileName));

                        // normalize text representation
                        doc.getDocumentElement().normalize();

                        JAXBContext jaxbContext = JAXBContext.newInstance(docClass
                                        .getPackage().getName());
                        Unmarshaller u = jaxbContext.createUnmarshaller();
                        conf = (T) u.unmarshal(new File(fileName));

                }

                return conf;
        }

        public static String readFile(String url) throws IOException
        {
                StringBuffer fileData = new StringBuffer(1000);
                BufferedReader reader = new BufferedReader(new FileReader(url));
                char[] buf = new char[1024];
                int numRead = 0;
                while ((numRead = reader.read(buf)) != -1)
                {
                        fileData.append(buf, 0, numRead);
                }
                reader.close();
                return fileData.toString();

        }

        /**
         * Validates XML document against a document-specified schema
         * 
         * @param fileName
         *            XML document file name
         * @return true if XML document is valid
         * @throws SAXException
         * @throws IOException
         */
        private static boolean validateXML(String fileName) throws SAXException,
                        IOException
        {
                boolean isValid = false;

                SchemaFactory factory = SchemaFactory.newInstance(W3C_XML_SCHEMA);
                Schema schema = factory.newSchema();

                Validator validator = schema.newValidator();
                Source source = new StreamSource(fileName);

                try
                {
                        validator.validate(source);
                        isValid = true;
                        System.out.println(fileName + " is valid.");
                }
                catch (SAXException ex)
                {
                        System.out.println(fileName + " is not valid because ");
                        System.out.println(ex.getMessage());
                }

                return isValid;
        }
}