A, Buffer buffer
Basic processing unit of the user data, the client sending and receiving data need be forwarded Buffer
Two, Channel Channel
Similar stream; but unlike IN / OUT Stream; stream having exclusive and one-way; flow channel is biased in favor of the diversity of data
Three, Selectors Selector
Distributed processing client for all events
Four, Charset extension
Charset Character Encoding: encryption, decryption
Natively supported, the data channel level data processing, may be used for data transmission level data encryption and decryption operations
Five, NIO-Buffer
Buffer include
ByteBuffer、CharBuffer、ShortBuffer、IntBuffer、LongBuffer、FloatBuffer、DoubleBuffer
Unlike traditional, write data is written to Buffer-> Channel; on the contrary read
Unlike traditional, write data is written to Buffer-> Channel; on the contrary read
Provide the basis for the data block NIO press operations "block" for transmission
A Buffer represents a "block" of data
Six, NIO-Channel
Can be obtained from the channel data may be output to the data channel; perform the "block" Buffer
Asynchronously write data can be complicated (but when the data is ordered, if the intermediate multithreading added other data, may lead to unusable data. Therefore, a normal read is a thread, a thread is writing)
Buffer read data read and write data, you must write data Buffer
包括：FileChannel、SocketChannel、DatagramChannel等
Seven, NIO duties
First of all, readable to register Channel Selector, writable state
When the client sends a message to the server, the card receives message, Channel in the readable state, notified Selector, Channel message is received, among the read data to the Buffer
