BackupFileUtil.java

package net.rrm.ehour.backup.service.restore;

import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamException;
import java.io.*;

/**
 * @author thies (thies@te-con.nl)
 *         Date: 1/20/11 5:36 PM
 */
public final class BackupFileUtil {
    private BackupFileUtil() {
    }

    /**
     * Write bytes[] to temp file and return the absolute filename
     */
    public static String writeToTempFile(byte[] bytes) throws IOException {
        final String xmlData = new String(bytes);

        File file = File.createTempFile("import", "xml");
        file.deleteOnExit();

        try (FileWriter writer = new FileWriter(file)) {
            writer.write(xmlData);
        }

        return file.getAbsolutePath();
    }

    /**
     * Create XML reader from data string
     *
     * @param xmlData
     * @return
     * @throws XMLStreamException
     */
    static XMLEventReader createXmlReader(String xmlData)
            throws XMLStreamException {
        XMLInputFactory inputFactory = XMLInputFactory.newInstance();
        return inputFactory.createXMLEventReader(new StringReader(xmlData));
    }

    /**
     * Create XML reader from file
     *
     * @param filename
     * @return
     * @throws IOException
     * @throws XMLStreamException
     */
    static XMLEventReader createXmlReaderFromFile(String filename) throws IOException, XMLStreamException {
        String data = getXmlDataFromFile(filename);
        return createXmlReader(data);
    }

    private static String getXmlDataFromFile(String filename) throws IOException {
        try (BufferedReader bufferedReader = new BufferedReader(new FileReader(new File(filename)))) {
            String line;
            StringBuilder xmlData = new StringBuilder();

            while ((line = bufferedReader.readLine()) != null) {
                xmlData.append(line);
            }

            return xmlData.toString();
        }
    }
}