Multithreading in Java

Multithreading: Multithreading in Java is a powerful mechanism that allows concurrent execution of multiple threads within the same program. It enables developers to create applications that can perform multiple tasks simultaneously, improving performance and responsiveness. Java provides a Thread class and Runnable interface to achieve thread programming.

Thread: Thread is a subprocess of the process that represents an independent execution path within the program. Threads are the instances of the Thread class and implement the Runnable interface. Each thread has its own call stack and executes code independently of other threads.

Thread Life Cycle: After creating any thread it goes through various states in its lifecycle,

1. New/Born state: The thread is created but not yet started.
2. Runnable state: The thread is ready to run and waiting for CPU time.
3. Running state: The thread is executing its task.
4. Blocked/Waiting state: The thread is temporarily inactive because it's waiting for a resource or lock.
5. Terminated/Dead state: The thread has completed its execution.

Thread Pool: Java Thread pool represents a group of worker threads, which are waiting for the task to be allocated. Threads in the thread pool are supervised by the service provider which pulls one thread from the pool and assigns a job to it. after completion of the task, the thread came to the thread pool. The ExecutorService interface is used for managing threads using thread pools. Thread pools improve performance by reusing the threads and managing their life cycle very efficiently.

Daemon Thread: Threads are used to provide service or background support to the user's threads, and are known as daemon thread. It is a low-priority thread and its life depends on user threads.

Synchronization: Synchronization in Java is the capability to control the access of multiple threads to any shared resource. Java synchronization is a good option where we want to allow only one thread to access the shared resources at a time. Synchronization is used to prevent threads interfarence and consistency problem.

DeadLock : In Multithreading, DeadLock is a situation in which every thread is waiting for a resource which is held by some other waiting thread. In this situation, Neither of the thread executes nor it gets the chance to be executed. Instead, there exists a universal waiting state among all the threads. Deadlock is a very complicated situation which can break our code at runtime.

Ways to avoid the deadlock condition in Java:

• Avoid Nested lock.
• Avoid unnecessary locks:
• Using thread join

Benefits of Multithreading :

• improved Performance: Multithreading allows applications to utilize multiple CPU cores efficiently, leading to better performance and responsiveness.
• Concurrency: Multithreading enables concurrent execution of tasks, enabling applications to handle multiple operations simultaneously.
• Asynchronous Programming: Threads can execute tasks asynchronously, allowing applications to perform non-blocking I/O operations and handle events concurrently.