Multithreading Scenarios in Java

Multithreading Scenarios

Every Java thread has a priority that aids in determining the scheduling order by the operating system. Java thread priorities fall between the constants MAX PRIORITY and MIN PRIORITY (a constant of 10). Every thread has priority NORM PRIORITY by default (a constant of 5).

A program should give higher priority threads more processing time than lower priority threads because they are more important. The execution order of threads cannot be guaranteed by thread priorities, which heavily depend on the platform.

Multithreading is the simultaneous execution of several threads. Java refers to the process of running multiple threads concurrently as multithreading. A program is referred to as multithreaded when it has multiple control flows.

Java refers to each program's subprogram as a thread. We are able to run multiple threads simultaneously thanks to multithreading. For instance, in a web browser, we can have one thread that manages the user interface and another thread running in the background that retrieves the data that will be displayed. Therefore, multithreading makes a system more responsive.

Run multiple tasks concurrently within a process. It comes in two varieties: kernel level threads and user level threads. It allows resource sharing and is economical, responsive, scalable, and efficient. Multithreading uses the many- to-many model, the many-to-one model, and the one-to-one model.

The CPU can switch between two threads to execute them simultaneously when a program has more than one thread. Context switching is the process of switching between two threads.

Because of how quickly one thread is switched to another, users may believe that all threads are running concurrently. But in fact, execute data time only involves one thread.

Applications that require the simultaneous completion of multiple tasks can benefit from this technique. Time - sharing is the practice of multiple threads sharing CPU time on a single processor system.

Resource allocation and scheduling are handled by the operating system. Multithreading maximises CPU utilisation while minimising CPU idle time, resulting in improved CPU performance.

Each thread in a multi-threaded program is given a single task to complete and runs independently. During execution, if an exception occurs in one thread, it has no impact on the other threads.

For instance, having one thread read data, another process it, and a third thread write it enhances an application's overall performance.

A multi-threaded program can download a file from the network, play music, and display animations all at once.

The following are some benefits of using the multithreading programming concept:

• Different threads execute different portions of an application in a multithreaded application program.
• Even if an exception arises in one of the threads, the entire application keeps running.
• During application execution, it has no impact on other threads.
• Each thread is executed in parallel across various processors after being assigned to various ones.
• The use of multithreading shortens computation times.
• The application performs better thanks to multithreading.
• The memory address space used by threads is the same. Thus, it conserves memory.
• A multi-threaded program uses the CPU to the fullest extent possible while minimizing CPU idle time.
• Context switching between processes is more expensive than context switching between threads.

Let's see few Java thread-based multithreading examples in real time as shown below:

1 . A browser that begins rendering a web page while it is still downloading the rest of the page is another well - known example.

Process-based multi-tasking or program-based multi-tasking is the practice of running several programs or processes simultaneously. The microprocessor runs multiple programs concurrently in process-based multi-tasking.

As a result, multi-processing is another name for it in Java. It is very substantial. A feature called process-based multi-tasking enables the computer to run two or more programs at once.

Running a spread sheet program while using a word processor is a good example. In the memory, each program (process) has a unique address space. In other words, a distinct memory space is assigned to each program.

For the operating system to switch from one program to another, some CPU time is needed. Context switching is the process of switching the CPU between running programs.