JAVA EE: Java Tutorial : Java Threads (Life cycle of a Thread in Java

Tuesday, 29 November 2016

Java Tutorial : Java Threads (Life cycle of a Thread in Java | Java thread life cycle_V6)

🚀 Want to Master Java Concurrency?

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What is a Thread Life Cycle in Java?

In Java, multithreading allows concurrent execution of two or more parts of a program to maximize CPU utilization. From creation to termination, every thread transitions through several distinct states managed by the JVM and OS scheduler.

Key States in Java Thread Life Cycle

New (Born): When a thread instance is created using the Thread class or Runnable interface, before calling start().
Runnable: After invoking start(), the thread becomes ready to run and waits for CPU time allocation from the thread scheduler.
Blocked / Waiting: When a thread is waiting to acquire a monitor lock or waiting indefinitely for another thread's notification.
Timed Waiting: When a thread waits for a specified time period (e.g., using sleep(ms) or join(ms)).
Terminated (Dead): When the thread finishes executing its run() method or terminates abruptly due to an unhandled exception.

Why Master Thread States?

Understanding these transitions helps you write robust concurrent applications, avoid common concurrency pitfalls like deadlocks and race conditions, and optimize system performance effectively.