Java NIO

Java NIO uses three core classes:

• Buffer: This holds information that is read or written to a channel
• Channel: This is a stream-like technique that supports asynchronous read/write operations to a data source/sink
• Selector: This is a mechanism to handle multiple channels in a single thread

Conceptually, buffers and channels work together to process data. As shown in the next figure, data can be moved in either direction between a buffer and a channel:

The channel is connected to some external data source, while the buffer is used internally to process the data. There are several types of channels and buffers. A few of these are listed in the following tables.

The table for channels is as follows:

Channel class	Purpose
FileChannel	This connects to a file
DatagramChannel	This supports datagram sockets
SocketChannel	This supports streaming sockets
ServerSocketChannel	This listens for socket requests
NetworkChannel	This supports a network socket
AsynchronousSocketChannel...