Non-blocking IO

• Reference: https://stackoverflow.com/questions/25099640/non-blocking-io-vs-async-io-and-implementation-in-java
• OS provides two ways of I/O:
  • Blocking I/O
  • Non-blocking I/O

Implementing sync and async IO

• Synchronous I/O:
  • Use Blocking I/O
• Asynchronous I/O:
  • Use Blocking I/O:
    • must use multi-threading
  • Use Non-blocking I/O:
    • single threaded
    • multi-threaded

Java NIO

• stands for New Input/Output
• original java.io blocks IO
• java.nio allows for non-blocking communication
• Netty is built on top of Java NIO client server framework