OOPS

Thread

A small path of execution of a program is called a thread.

Threads have two types primarily:

• Kernel thread.
• User thread.

An operating system has various threads & subroutines for various things like I/O, networking & print spooler etc.

Mutual Exclusion

The order of execution is not defined in two or more independently existing/running threads.

Mutual exclusion gives programmer ability to define/control this behavior (the order of execution & synchronization etc.).

Leslie Lamport

Multi-Tasking

Multi-process: Multiple processes.

Concurrency: Multi-threading.

Lifecycle Of A Thread

• Newly Born
  • Creation of the thread.
• Ready
  • Created.
• Running
  • Working state.
• Blocked
  • Blocked by some other thread.
• Dead
  • Thread is terminated.

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Thread Synchronization

Thread synchronization in Java is done with:

• Ownership flag.
• Ownership freeing flag.

Keywords & Methods:

• wait
• notifyAll
• synchronized