gistfile1.java

channel = new FileInputStream(dbFilePath).getChannel();
            ByteBuffer buffer = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
            try {
                while (buffer.remaining() > 0) {
                    int keySize = buffer.getInt();
                    byte[] key = new byte[keySize];
                    buffer.get(key);
                    int valueSize = buffer.getInt();
                    byte[] value = new byte[valueSize];
                    buffer.get(value);
                    cache.put(new String(key, "UTF-8"), new String(value, "UTF-8"));
                }
            } catch (BufferUnderflowException e) {
                System.err.println("Corrupted file");
                System.exit(1);
            }