public MappedRandomAccessFile(String filename,
    String mode) throws IOException, FileNotFoundException 
{
    
        if (mode.equals("rw"))
            init(
                    new java.io.RandomAccessFile(filename, mode).getChannel(),
                    FileChannel.MapMode.READ_WRITE);
        else
            init(
                    new FileInputStream(filename).getChannel(),
                    FileChannel.MapMode.READ_ONLY);
}

Constructs a new MappedRandomAccessFile instance

Parameters:

filename - String

mode - String r, w or rw

Throws:

FileNotFoundException -

IOException -

 public static boolean clean(ByteBuffer buffer) 
{
        if (buffer == null || !buffer.isDirect())
            return false;
        Boolean b = (Boolean) AccessController.doPrivileged(new PrivilegedAction() {
            public Object run() {
                Boolean success = Boolean.FALSE;
                try {
                    Method getCleanerMethod = buffer.getClass().getMethod("cleaner", (Class[])null);
                    getCleanerMethod.setAccessible(true);
                    Object cleaner = getCleanerMethod.invoke(buffer, (Object[])null);
                    Method clean = cleaner.getClass().getMethod("clean", (Class[])null);
                    clean.invoke(cleaner, (Object[])null);
                    success = Boolean.TRUE;
                } catch (Exception e) {
                    // This really is a show stopper on windows
                    //e.printStackTrace();
                }
                return success;
            }
        });
        return b.booleanValue();
}

invokes the clean method on the ByteBuffer's cleaner

 public  void close() throws IOException 
{
        clean(mappedByteBuffer);
        mappedByteBuffer = null;
        if (channel != null)
            channel.close();
        channel = null;
}

 protected  void finalize() throws Throwable 
{
        close();
        super.finalize();
}

invokes the close method

 public FileChannel getChannel() 
{
    	return channel;
}

 public long getFilePointer() 
{
        return mappedByteBuffer.position();
}

 public long length() 
{
        return mappedByteBuffer.limit();
}

 public int read() 
{
        try {
            byte b = mappedByteBuffer.get();
            int n = b & 0xff;
            return n;
        } catch (BufferUnderflowException e) {
            return -1; // EOF
        }
}

 public int read(byte[] bytes,
    int off,
    int len) 
{
        int pos = mappedByteBuffer.position();
        int limit = mappedByteBuffer.limit();
        if (pos == limit)
            return -1; // EOF
        int newlimit = pos + len - off;
        if (newlimit  > limit) {
            len = limit - pos; // don't read beyond EOF
        }
        mappedByteBuffer.get(bytes, off, len);
        return len;
}

 public  void seek(long pos) 
{
        mappedByteBuffer.position((int) pos);
}