method of copy file

FileUtil.java

/**
 * copy file
 * @param source
 * @param dest
 * @throws IOException
 */
public static void copyFileUsingFileChannels(File source, File dest)
        throws IOException {
    FileChannel inputChannel = null;
    FileChannel outputChannel = null;
    try {
        inputChannel = new FileInputStream(source).getChannel();
        outputChannel = new FileOutputStream(dest).getChannel();
        outputChannel.transferFrom(inputChannel, 0, inputChannel.size());
    } finally {
        inputChannel.close();
        outputChannel.close();
    }
}

// convert InputStream to String
// NB: does not close inputStream, you can use IOUtils.closeQuietly for that

public static String convertISToString(InputStream inputStream,String encoding){
    String theString = IOUtils.toString(inputStream, encoding); 
    IOUtils.closeQuietly();
    return theString;
}