Concurrency

Concurrency

• Thread - It is smaller unit than process, each thread can be scheduled independently and has its own stack and program counter but shares memory and objects with other threads in the same process.
• Thread Lifecycle:
  • NEW - created, but not started yet
  • RUNNABLE - is running or is available to run
  • BLOCKED - not running, waiting to acquire lock
  • WAITING - not running because it has called Object.wait() or Thread.join()
  • TIMED_WAITING - not running because it has called Thread.sleep()
  • TERMINATED - execution completed
• Thread methods:
  • getId() - id number of thread
  • setName() - getName(), name of the thread can be set
  • getState() - returns Thread.State
  • isAlive() - is thread still alive?
  • start() - creates new application thread and schedule it
  • interrupt() - the interrupt status of the thread will be set to true
  • join() - thread waits until the thread corresponding to the Thread object has died
  • setDeamon()
  • DO NOT USE: stop(), suspend(), resume(), and countStackFrames(), destroy()