Java is a programming language which generally classes based, object-oriented and use to have a dependency. The popularity of java language is related to GitHub, a client-server web application and the key behind this web is threading java program. The most successful threading version is multithreading in java the give the flexibility of multiprocessor and multitasking. The concept of multithreading is very popular among programmers.
Thread is defined as a lightweight process to execute programs that run on the CPU. It can be called the unit of execution task in CPU. To maintain and carry out the task at one thread is must be needed. There are multiple threads can be used under a single process to work parallelly by sharing information. In a brief, it is a single sequential flow of control within a program.
The system is used to handle simultaneous processes. It is the smallest independent unit of a program. There are different types of treading process such as single treading and multithreading. For example, an operating system, java web browser.
Thread in java
To execute any kind of task in computer treading process is required which complete task by the core of the central processing unit in a computer. Java also has a treading system that creates the structure to carry on task until it is finished. Treading in java allows efficiently utilizing the processing unit. Generally, in java program by default, at least one thread is always there and it is called the main thread.
Main tread it the skeleton structure of the process and it can be divided into various treads which are called multi threads and the process is called multithreading. In a single java treading system, the CPU is used completely to process that particular thing and not other programs can be run on it. This is a sequential way to execute the task using the available data.
Thread life cycle
Threading process consists of a pathway which includes several stages. The individual stage can be operated in a particular time not all are at once. The states are given below with their functions.
- New: A new thread starts its life cycle in this state and keeps remaining here until the program began. It is popularly known as the born tread.
- Runnable: The newly born thread is stand by on this state. It is not running by ready for executing the task.
- Running: In this state, a thread decides which one how to execute the process. It checks the input data and convert to yield. If any fault or error is found, it sends back to the runnable state for correction. The method takes some time to deliver the outcome.
- Non- runnable: It is prevented from entering into the runnable and running state. A thread enters this state when it is inactive for the time being but it is alive but not compatible to run. It can happen when the thread is suspended, sleeping, blocked or waiting to satisfy certain requirements. A blocked thread is considered not runnable but not dead and therefore fully qualified to run again.
- Terminated: After completing the task a thread is terminated and it is called natural death. If the thread is stopped without execution than it is called premature death.
Multithreading in java
Java is known for its multithreading programming language. So, it is highly possible to create and develop multiple threading program using java. Multithreading is a process where multiple threads are concurrently carrying out to complete the task. Every application has at least one thread and it is called main thread alongside main thread when other threads are parallel running then it is called multithreading.
In java, it is a feature that allows completing different parts of the program for efficiently use of CPU and reduce the time of processing. Java program consists of several parts and it is possible to run all of them at the same time and this multi-thread engagement in the same platform but independent in their nature and function, the theme is known to be multithreading.
Functional advantage of multithreading
As we know multithreading allows to maintain and complete various parts of a program at once. It helps to exploit the capacity of the computer CPU. There are several benefits to this process which is given below.
- Sharing resource of all the threads such as memory, data and files effectively. An application is accumulated with lots of threads which can be executed by using the same resource sharing.
- If one part of the program is blocked other can run due to its program responsiveness. Multithreading can be done to maintain larger programs and a web browser is a perfect example to run different work at the same time.
- In this process, one can utilize the full potential of their processor. If one has a multiprocessing unit, then different threads can be parallel. It is can save time as well.
- The process is economically cheap and extra expenses are cut down. Due to use multithreading helps to utilize the best version of your device and reduce the time for execution.
- It does not block the user. So, they can work smoothly.
- Threads are independent so it does not affect other threads.
- Each thread has its private run-time stack.
- If two threads execute the same method, each will have its copy of the local variables the method uses.
- Two different threads can act on the same object and same static fields concurrently.
- Less costly because you can switch between threads.
- The communication expenses are very low that way it is popular.
- The performance of the application dramatically increases.
- It helps to simplify the streamlined program coding. It allows the splitting task in different treads that more convenient. Complex programs are easy are design and codes are adaptive too.
Application of multithreading
The reason for multithreading is to run two or more programs equivalently at the same time.
- Multithreading system helps to download different files and tabs of various pages with the help of a browser. If the system was not available, we would not be able to browse different page within a moment and lack of this feature in the application will block other pages when we would use browser.
- Web service would not be possible if multithreading was not applied. It handles each individual in a different thread.
- In computer gaming, diverse elements are manoeuvred for example in a racing game with include cars, racing track, multiple players, music and obstacles etc. which are being distributed in a solo thread but maintained by interconnected multithreading.
- When you are editing text in a text editor, writing, spelling check, saving file are happening simultaneously and it is done by multithreading.
- You can open multiple programs on IDEs android studio and enjoy the moment but it is also done by multithreading.
- Scanning malware-fighting program this process also occurs.
Creating a thread in java
Threads are implemented in the form of objects. For the implementation of thread to intergrade methods are used which are run() and start(). The run() method is the key to all treads. It makes the whole structure of a thread body. This run() method can be initialized with the help of the start method. There are two ways to create a thread.
- Extending the thread class
- Implementing the runnable interface
Extending the thread class
- The subclass overrides the run() method of thread class.
- An object instance of the subclass can then be created.
- Calling the start() method of the object instance starts the execution of the thread. Java runtime starts the execution of the thread by calling run() method of the object instance.
Implementing the runnable interface
- A class that defines the implementation of the runnable interface.
- It has only one method run(), that is to be defined in the method with the code to be executed by the thread.
- Creates a new thread and makes it runnable.
- This method can be called only once.
- The new thread begins its life inside this method.
- The thread is being terminated.
- Causes the currently executing thread object to temporarily pause and allow other threads to execute.
- Allow only threads of the same priority to run.
sleep(int m or n)
- The thread sleeps for m milliseconds, plus n nanoseconds.
Every thread has a priority. It plays a vital role in processing the system.
- When a thread is created, it inherits the priority of the thread that creates it.
- Each thread is assigned a priority, which affects the order in which it is scheduled for running.
- The priority values range from 1 to 10, in increasing priority.
- It can be adjusted subsequently using the setPriority() method.
- The priority of a thread may be obtained using getPriority().
- Priority constants are defined: MIN_PRIORITY=1, MAX_PRIORITY=10 and NORM_ PRIORITY=5.
Daemon threads are a helping tread that assists to performer threads to execute the program completely. Assistant daemon thread it presents when the working is going on. After completing the task, the thread moves away from the place. They are also called the background of the threading system. It is a common feature in java virtual machine (JVM).
Objectives of the daemon threads
- Non-daemon threads are supported by the daemon thread.
- The main purpose of this thread is to maintain background task so its work is garbage cleaning.
Priorities of daemon threads
- The priority level of the daemon thread is very low.
- Used threads decision is final wither or not it exists.
- They run in the same process but act as a service provider to user threads.
- It’s executing is related to java VM but not in a mandatory manner.
Stopping a thread
- For stopping thread from running, you may call stop() method.
- This causes the thread it’s the dead state.
- It forces the thread to stop suddenly without any conclusion.
- The behind is for premature death.
Blocking a thread
- A thread can be blocked for a shorter period of blocked form entering into the runnable and running state.
- sleep(t)//blocked for “t” milliseconds.
- suspend()// blocked until resume () method is invoked.
- wait()//blocked until notify () is invoked.
- Generally, threads use their data and methods provided inside their run() methods.
- If we wish to use data and methods outside the threads run() method, they may compete for the same resources and may lead to serious problems.
- Java enables us to overcome this problem using a technique known as synchronization.
- For example, One thread may try to read a record from a file while another is still writing the same file.
- When the method declared as synchronized java creates a monitor and hands it over to the thread that calls the method the first time.
- Deadlock describes a situation where two or more threads are blocked forever, waiting for each other.
- In that time two or more threads are waiting to gain control on a resource.
- For example: think that tread A must access method 1 before it can release method 2, but thread B cannot release method 1 until it gets holds of method 2.
In this modern era, the software revolution is changing the functional and user experience of computer and other devices. Java is one of the renowned programming languages out there that enable to give application threading system. In the threading process, main thread in by default present on the other hand multithreading is a unique feature in java that helps in multitasking.
Using multithreading application running, processing time and expenses reduced a lot. With the help of this function in java, the application is becoming user friendly and easier to maintain. In conclusion, it can be said that multithreading is a breakthrough in java program coding. Those who are tech lovers can make something new with this feature.