In Java, the thread life cycle follows a specific set of states. Here is an explanation of the thread life cycle from a Java perspective:
Thread Life Cycle States
New State: This is the initial state of a thread when it is created but has not yet started its execution. The thread is represented by an instance of the Thread class or by implementing the Runnable interface and passing it to a Thread object.
Runnable State: Once a thread is ready to run, it enters the runnable state. It means that the thread can be scheduled by the Java Virtual Machine (JVM) to run, but it may or may not be currently executing. Threads in the runnable state can be executed concurrently.
Running State: When a thread is selected by the JVM’s thread scheduler, it enters the running state. The thread’s run() method is invoked, and it starts executing its designated code. In this state, the thread is actively using CPU resources.
Blocked/Waiting State: A thread can enter the blocked or waiting state for various reasons, such as waiting for I/O operations, acquiring a lock, or waiting for a condition to be satisfied. When a thread is blocked, it temporarily gives up the CPU and does not consume CPU resources until the blocking condition is resolved.
Timed Waiting State: Threads can enter the timed waiting state when they are waiting for a specific amount of time. This state is similar to the blocked/waiting state but with a time limit. Threads can enter timed waiting states by invoking methods such as Thread.sleep() or Object.wait(timeout).
Terminated/Dead State: When a thread completes its execution or is explicitly terminated by invoking the Thread object’s stop() method (deprecated since Java 1.2), it enters the terminated or dead state. In this state, the thread has finished its tasks, and its resources are released. Once a thread is terminated, it cannot be restarted or resumed.
It’s important to note that Java provides various methods and constructs for thread synchronization and communication, such as synchronized blocks, locks, and wait-notify mechanisms. These can affect the transitions between the different thread states.