Java run in background thread Any code that updates the UI or interacts with the user should be run on the main thread. However, as with any powerful Apr 17, 2023 · Use the following command to run the application: mvn spring-boot:run The application will start and the scheduled job will run at the specified interval in a separate thread. I would like a progress spin May 8, 2021 · I wonder what is the good practice in Quarkus to run background task per request. is this fine and correct way of behaviour?" Though the main thread completes, the JVM doesn't shut down until Jan 22, 2020 · I am trying to build a Spring Boot application that will run a long running thread in the background but the problem I am having is that I cannot autowire spring beans in the thread (at least the w Jul 23, 2025 · The main thread, also known as the UI thread, is responsible for handling all UI updates and user interactions. This poses a problem, as only the main thread can update the UI. The solution is to use the runOnUiThread() method, as it allows you to initiate code execution on the UI thread from a background Thread. This is understandable since the daemon thread does not need to provide services to another thread when all of them are running. You have to synchronize them, and one of the ways to do that is using the class CountDownLatch. Usage Deemed threads are mainly used to provide background support for user threads. Aug 15, 2010 · In your "main" thread, create a new Thread class, passing the constructor an instance of your Runnable, then call start() on it. It is a lightweight subprocess that runs independently but shares the same memory space as the process, allowing multiple tasks to execute concurrently. The run () method can be called in two ways which are as follows: Using the start () method. run() is going to execute the code in the thread's run method on the current thread. Also note that AsyncTask. Worker threads are used for background tasks that should not block the main thread, such as network requests, database operations, and image processing. You're running this once at the moment and regardless of the result the thread hits the end. Jul 21, 2009 · I wrote a library Background. When the application starts I want to start a worker Thread in the background that Spring Autowires with some dependencies. Usage Threads are used in Java to perform background operations without interrupting the main program flow Oct 29, 2008 · Ok i found the reason - there are two additional AWT threads running and that's why my application doesn't end when the "main" method ends. "this gets printed before the system. You can use that for things that only happen once in a while; otherwise you are probably better off creating your own instance We would like to show you a description here but the site won’t allow us. The answer is: It depends on what you want to do in that job. Learn how to create background threads in Java that run independently and do not interfere with the main program's execution. This guide covers threading, task management, and best practices for efficient execution. Jul 8, 2016 · I would like to put all the code that fetches the content and displays it in a background thread and while the program is doing those functions , I would like to display a progress dialog. With list of thousands of APIs and utilities you could create any types of tutorials. May 2, 2024 · So I'm trying run an ExoPlayer on a background thread because it sometimes blocks for up to several seconds at a time when releasing (I'm using an RTSP media source. concurrent package or Kotlin coroutines instead of the traditional Thread class. Sep 23, 2012 · In this approach, the main program will create a new thread that runs the background process, and the main thread will continue executing without waiting for the background thread to complete. Conclusion Introduction In the world of concurrent programming in Java, daemon threads are a fundamental concept that allows developers to create background tasks for their applications. Jul 23, 2023 · Java is pretty amazing. The ThreadPool is generated through one of the Executors ' methods (don't know which yet) with a user-specified Thread count. Both is most easily Nov 24, 2015 · IMPORTANT: Remember to call handlerThread. RequestProcessor. This tutorial explores what daemon threads are, how they work, and their role in Java's threading model. There are two ways to create a thread. Efficient resource utilization: Threads share the memory of the main process, making them lighter than creating entirely new processes. Every thread has a priority. Unlike user threads, daemon threads do not May 28, 2021 · A Thread is useful if you have long-running tasks which do not happen all the time. I heard about AsyncTask class which can be used to execute code in background process but in Android documentation i found that it was deprecated from API Level R. concurrent but it is more typical to use RequestProcessor. These threads are of low priority and are typically used for tasks that do not need to be run to completion. Apr 22, 2023 · java. Run the network code in doInBackground() and update the UI on any of the other methods. post(runnable, delay); Where runnable should be run in background Jul 23, 2025 · The AsyncConfig class provides an Executor bean that is used to run asynchronous tasks. Here is an example: Jul 23, 2025 · Java threading is the concept of using multiple threads to execute different tasks in a Java program. Corresponding to each Timer object is a single background thread that is used to execute all of the timer’s tasks, sequentially. It is a GUI application where you can create/modify/del Oct 4, 2020 · You need to override the run () method of the thread and put all the statements you want to run in the background inside it. jar & nohup prevents the process from being terminated when the terminal session ends. After that, what’s left to do is to instantiate Worker and run it, as shown in Listing 11-5. Oct 11, 2025 · A Java thread is the smallest unit of execution within a program. For each pane I have to first run a computation of the content (about 300ms) and then I have to build the Panel (about 500ms). You need an infinite loop essentially, followed by a break upon the correct condition being found. I want to run this in another thread while the rest of my program finishes starting up. However, the thread does not seem to be running in the background, and the actions taken inside the runnable are st Daemon Thread in Java A daemon thread in Java is a service provider thread that runs in the background and provides services to user threads. Override the run () method, this is where you put the code that the thread should execute. concurrent package to perform something in the background. Its lifecycle depends on the existence of user threads; when all user threads finish execution, the JVM terminates the daemon thread automatically. Android has several options for running tasks in the background and in this article, we'll look at So sometimes you will want to move expensive or slow work onto a background thread. Jun 1, 2023 · Also, using Java Threads did not work because quarkus waited until the thread was finished with the REST response. This guide will walk you through the ins and outs of using the Timer class in Java, from creating a basic timer to scheduling complex recurring tasks. out. In other words, JVM can shut down even if a daemon thread is running. A daemon thread in Java runs in the background to perform auxiliary tasks and doesn't prevent JVM shutdown. Could you help me do this ? I would like especially to learn how to put the code in a background thread. Learn how to implement background processes in Java. May 8, 2012 · To kill the thread, set run to false. These background tasks will remain active as long as there are normal tasks running. The Java Virtual Machine allows an application to have multiple threads of execution running concurrently. ) There is a general purpose built-in thread pool - RequestProcessor. When performing tasks that support the main operation, they do not interfere Aug 5, 2018 · In Java/Android, is there a way to check whether the currently executing line of code is executing on a background thread or not? I have a lil' program I'm conjuring up that has finally reached th Aug 26, 2017 · By default, the thread is set to daemon. Using the run () method itself. If you are running on some background thread, but need to modify some Swing component, a simple way to do this is <pre> Apr 23, 2025 · Mastering Java Background Jobs: Threads, Pools, Virtual Threads, and JobRunr We’ve all been there. Java threads are a fundamental part of Java's concurrency model, allowing multiple tasks to run concurrently within a program. Otherwise, this method does nothing and returns. You want thread. If you want to use it as an asynchronous worker, you can use a message queue. User Threads Priority The JVM exits when it’s the only daemon thread remaining in a process. These tasks can run on any system, even those without Java installed. It checks if the Java version supports virtual threads and configures the executor accordingly. execute() requires you to call from the UI thread anyway, which renders this option useless for the use case of simply running code on the UI thread from a background thread unless you move all of your background work into doInBackground() and use AsyncTask properly. runLater to do things in the JavaFX Application thread from the background thread. Be careful when invoking either overload of get from the event dispatch thread; until get returns, no GUI events are being processed, and the GUI is "frozen". A thread is a thread of execution in a program. Use Case: Useful for running multiple background tasks concurrently with Nov 11, 2025 · Android supports the usage of the Thread class to perform asynchronous processing. Oct 24, 2016 · Why background task? There are tons of examples where we often need to run a task in background e. At the end of the day I just want to have that task which takes so much time running in background without waiting for the answer in the REST call. The other option is to create a subclass of Thread (not just in line overriding methods) and create a method halt() (stop is final). Yes. Today I had a scenario in which I needed to have my program running forever. Such processes that are "out of control" of the framework cause most of time very annoying problems. One way to achieve this is by manually spawning threads using the Runnable interface. I don't know how to do that. Mar 8, 2023 · If your task is quite simple and you just want to run it in background, then it's totally doable by Java's CompletableFuture class, which represents a potentially asynchronous operation that can be completed in the future with a result or an exception. Jan 9, 2018 · I want to create a thread with the infinite while loop and after sometime starting that thread my requirement is to restart the thread. Apparently there is no real way to run something in the background and many recommend using setTimeout(); For example this one How to get a group of js function running in background Mar 30, 2021 · I am writing an Application similar to windows' file explorer in Java (JavaFX). Dec 4, 2012 · If you're writing a desktop or Java Web Start program in Java using Swing, you might feel the need to run some stuff in the background by creating your own threads. Usage Threads are used in Java to perform background operations without interrupting the main program flow May 23, 2024 · In Java, multithreading is a powerful feature that allows multiple threads to run concurrently, providing a means to perform background tasks, handle multiple client requests, or improve performance through parallel processing. Threads with higher priority are executed in preference to threads with lower priority. To mitigate this, long-running operations should be run in the background. Also, I wouldn't make an anonymous subclass of thread, but instead make a Runnable and pass it to the thread constructor. js to handle a few scenarios: a sequential background queue (based on the WorkerQueue library), a list of jobs where each is called on every timer, and an array iterator to help break up your work into smaller chunks. But from the application programmer's point of view, you start with just one thread, called the main thread. Then you can create a thread whenever needed and it will be destroyed as soon as it's done executing. Oct 2, 2024 · Learn how to master multithreading in Java and Spring Boot. It also explains how to create daemon threads that do not keep the Java Virtual Machine running after the main application thread exits. Jan 14, 2025 · A daemon thread is a special type of thread in Java that runs in the background and performs tasks such as garbage collection or other low-priority jobs. Dec 18, 2024 · The run () method is available in the thread class constructed using a separate Runnable object. It can be created by extending the Thread class and overriding its run() method: Another way to create a thread is to implement the Runnable interface: Sep 9, 2013 · I want to run some Runnable in a background thread. Jul 8, 2014 · As you can see, there are some code that only ensures an eligible thread is used. Learn how to use concurrent library to execute long-running tasks in JavaFX 2. The background thread comes from the Executor specified in WorkManager's Configuration. Daemon threads are specialized threads in Java that run in the background and do not prevent the JVM from exiting when the program finishes executing. start tells the JVM to do the magic to create a new thread, and then call your run method in that new thread. Unlike user threads, daemon threads do not Sep 19, 2013 · I've been searching for an answer how I can run my save function in the background. What I want is, that t Jul 12, 2011 · I am pulling around 1500 data plots and adding them to overlays for an map view. Using the start () method We can If the background task is not finished, get blocks until it is — unless the timeout expires first, in which case get throws java. Threads can be used to perform complicated tasks in the background without interrupting the main program. println () in the child threads. This allows you to manage and execute asynchronous tasks without freezing the user interface or main application flow. In this simple example, a Thread is started when Nov 11, 2024 · If you want to run the Java application in the background, allowing it to keep running even after you log out from your terminal, use nohup (no hangup): nohup java -jar myapp. How to run tasks in background in Java? In Java, the easiest way to run a task in background is Multithreaded execution is an essential feature of the Java platform. Running long-running operations on the main thread can lead to app freezes, unresponsiveness and thus, poor user experience. Wanted to check upstart script in Ubuntu OS. AsyncTask is a helper class that allows Dec 3, 2012 · Multi-threading in Java Swing with SwingWorker If you’re writing a desktop or Java Web Start program in Java using Swing, you might feel the need to run some stuff in the background by creating your own threads. May 23, 2024 · In Java, multithreading is a powerful feature that allows multiple threads to run concurrently, providing a means to perform background tasks, handle multiple client requests, or improve performance through parallel processing. Mar 1, 2013 · Event handlers are a good way to go, but then you get even more threads that you have to worry about, because events should not be fired on the main thread, nor on the server thread, but should instead be queued in a separate event queue and related thread. – Rogue CommentedMay 8, 2017 May 28, 2021 · A Thread is useful if you have long-running tasks which do not happen all the time. Jun 23, 2012 · I want to know, how to keep a method running in the background. quit () when you are done with the background thread or on your activities onDestroy () method. These threads are automatically terminated when the main program terminates, making them ideal for performing background tasks that should not block application shutdown. halt() will set run to false. Relevant JavaDoc The repaint method doesn't actually repaint immediately. This feature allows you to execute methods in a separate thread, freeing up the main thread to continue processing. On the other hand, RxJava, a library for composing asynchronous and event-based programs using observable sequences, has become a standard in reactive programming. We have a lot of different ways to do a non-blocking UI operation (working on a different thread), t o name a I want to load up to nine panels in a TilePane. Jan 15, 2015 · This is a general Java question and not an Android one first off! I'd like to know how to run code on the main thread, from the context of a secondary thread. When code running in some thread creates a new Thread object, the new Aug 20, 2024 · Troubleshooting Async Issues in Java 8 CompletableFuture & RxJava Java introduced the CompletableFuture class in Java 8, opening the door for developers to embrace asynchronous programming with ease. This tutorial also explains how to stop a thread. lang. By default, WorkManager sets up an Executor for you—but you can also customize your own. If a task is not required to maintain atomicity and can be executed after some delay, it's a good candidate to run in background. This was a simple question that can be answered with a simple change. Explore essential techniques, from basic thread management in Java to asynchronous programming. Java threading programs use the classes and interfaces provided Jun 23, 2012 · I want to know, how to keep a method running in the background. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. There’s nothing stopping you from using standard multi-threading techniques in Swing, and the usual considerations apply. The process (a cmd one) should run only when the Nov 19, 2020 · 0 is there any new method to run in background like asynctask ? Will WorkManager solve this problem in java? or how to run in background thread in java ? Now I need to request data in server by using background thread May 27, 2020 · Based on the result obtained from the background thread I need to display an alert message on the UI. but making the user wait is simply not an option. ie. Aug 30, 2012 · 4 thread. May 10, 2010 · 9 I was wondering which would be the most efficient approach to implement some kind of background task in java (I guess that would be some kind of nonblocking Threads). 2. I want to use Handler because it's convenient for delays. It provides the Eclipse Jobs framework, which allows you to run operations in the background and provides feedback on the job status to the Eclipse platform. doWork() on a background thread. Learn how to execute background processes using threads in Java with code examples and best practices for efficient programming. this made me think that the main thread (class which has main method) can exit even before the child threads. Please help :-) Thank you, schube Nov 25, 2020 · As you are looking for reputable sources, here is the official documentation on exactly this problem - communicating a result from background thread to the main thread in plain java. Consider each HTTP request will be serviced very quickly in the UI thread. It is common to use a background Thread for doing network operations or long running tasks, and then update the UI with the results when needed. correct?". Creating new JVM threads, so that application code can have multiple threads of running code, is a low-level JVM operation. To be more precise - I have some java code and then at some point I need to execute a long running operation. As puce says, you have to use Task or Service for the things that you need to do in background. Immediate tasks For tasks that ought to be executed immediately and wish continued processing, albeit the user puts the appliance in the background or the device restarts, we recommend using WorkManager and its support for long-running tasks. If a timer task takes Aug 29, 2019 · The goal is to be able to invoke execution of a separate thread from within the main class. openide. If run() were exposed to the user, and it were called instead of start(), then the code in run() will be executed Mar 19, 2020 · As in EJB you should not do such things with a background process. Tasks may be scheduled for one-time execution, or for repeated execution at regular intervals. Some context: I have a program that must run a process. . 0 applications and how to use threads. We have a lot of different ways to do a non-blocking UI operation (working on a different thread), t o name a Whether you are performing background tasks, implementing concurrency, or managing multiple threads, the run() method provides used for controlling thread behavior in Java. Deferred tasks Every Mar 11, 2012 · "Here you mean "main thread" to be Java run time not the program with main method () . We can call the run () method multiple times. Sep 30, 2025 · As only the main thread is allowed to modify the user interface, the Eclipse framework provides ways for a thread to synchronize itself with the main thread. It is a GUI application where you can create/modify/del Java threads are a fundamental part of Java's concurrency model, allowing multiple tasks to run concurrently within a program. How can I avoid copying this "threading" code over and over for each method that should be run in a background thread? Threads can be used to perform complicated tasks in the background without interrupting the main program. Sep 2, 2024 · A focused tutorial about multithreading in Kotlin using Threads and Coroutines. I could definitely do that by running Tomcat process but why not we simply create a Java Program which runs forever. Real life examples Daemon threads are used for tasks Oct 24, 2016 · Why background task? There are tons of examples where we often need to run a task in background e. MY CODE Jan 28, 2025 · For example, if you want to play some music, but only while your activity is running, you might create a thread in onCreate(), start running it in onStart(), and stop it in onStop(). Timer provides facility for threads to schedule tasks for future execution in a background thread. It is terminated when all user threads finish. May 9, 2025 · Learn how to run background jobs in Spring Boot using threads, @Async, and scheduled tasks without any external tools or services in your application. A thread is a lightweight sub-process that runs within a process and shares the same memory space and resources. In specific cases, like with media playback or active navigation, you would possibly want to use foreground services directly. Each thread may or may not also be marked as a daemon. Mar 24, 2021 · TL;DR: Android apps use the main thread to handle UI updates and operations (like user input). A background thread is any thread that is not the event thread. Jul 13, 2024 · The benefits of using Java threads are: Improves responsiveness: The program can keep the user interface responsive while performing long-running tasks in the background (separate threads). TimeoutException. Methods onPreExecute - it's used to run some routine before the background task has started doInBackground - it's used to perform background tasks Jan 3, 2024 · Threading in Worker bookmark_border When you use a Worker, WorkManager automatically calls Worker. Aug 8, 2016 · How to run a retrofit in the background thread? I enter the word to text and then click on the button and in the output the result,simple translator, I test this library Mar 30, 2021 · I am writing an Application similar to windows' file explorer in Java (JavaFX). Jan 20, 2016 · In general, when choosing a Java Executor for your background computation needs, you have to consider three main questions about the nature of the work it will perform: How many threads do you want to run in parallel by default? What should the executor do with a submitted task when all available threads are busy working? Jun 20, 2012 · In an Android service, I have created thread(s) for doing some background task. concurrent. g. run will still be a global boolean. Oct 25, 2021 · 2 While the thread is sleeping, I exit my app. I have a situation where a thread needs to post a certain task on the main thread's message queue, for example a Runn Aug 22, 2013 · What is the best way to create a background thread that will run every 15 minutes to get the data from the database? Below is the code I have which will work fine I guess in production but is ther Sep 28, 2016 · I have a Spring Boot application deployed in Tomcat 8. It basically tells the JPanel that it ought to repaint itself soon. Please help :-) Thank you, schube May 26, 2012 · Multi-threading in Java is done by defining run() and invoking start(). Example: Thread th = new Thr Jul 24, 2017 · How can I run some process in background using Spring Boot? This is an example of what I need: @SpringBootApplication public class SpringMySqlApplication { @Autowired AppUsersRepo appRepo May 21, 2024 · Executors Explanation: Executors is part of the Java concurrent framework, managing a pool of threads for background tasks. Aug 26, 2014 · My application is to use nanoHTTPD as an alternative to pressing buttons and keying in text on an Android UI for automation and regression test I currently have a main UI thread and a customized nanoHTTPD running in a different thread. Timer tasks should complete quickly. Whether you are performing background tasks, implementing concurrency, or managing multiple threads, the run() method provides used for controlling thread behavior in Java. Also consider using thread pools and executors from the java. Start delegates to a native method that launches a thread through operating system routines and run() is invoked from withi Nov 25, 2020 · As you are looking for reputable sources, here is the official documentation on exactly this problem - communicating a result from background thread to the main thread in plain java. A thread is a lightweight process that enables parallel execution of code, improving application performance and responsiveness, especially in multi-core systems. Learn how to run Java applications in the background effectively with best practices and code examples. Apr 14, 2016 · I have, to my knowledge, implemented a runnable which is created on a new thread. On many (most?) devices, that will terminate your process, particularly if you do not have a service running. Get Free GPT4o from https://codegive. Jun 22, 2024 · Creatings threads in Java to run in the background is a common task for developers to handle asynchronous operations efficiently. Apr 3, 2019 · Two things: this background thread needs to be access workItems and update a variable which is visible to main via getFactor() I was looking at ExecutorService executorService= Executors. getDefault(). Mar 6, 2025 · Daemon vs. The process (a cmd one) should run only when the Dec 26, 2022 · Daemon thread A daemon thread is a java thread that runs in the background. If you want to execute tasks on a regular base you could use timers. Jul 17, 2012 · Is it possible to create a separate background thread which would separately do some stuff? I've tried the following program but it doesn't work as I expect. Every application has at least one thread — or several, if you count "system" threads that do things like memory management and signal handling. newSingleThreadExecutor(); but none of the tutorials i've seem suggest it can see the namespace of the thread's parent. Thread class to create our own java thread class and override run() method. The program is just for practising (it is my first ever app). In Java, starting a background thread that does not block the main thread can be efficiently handled using the Executor framework. Your web application needs to do something time-consuming; send an email, process an uploaded file, generate a report,. public class Test { private static In our first lesson of this section on Java concurrency we look at multithreading and how to run parts of a program concurrently by subclassing the Thread class. this method starts when the program starts and keeps executing its statements until the program is closed. start(). run is a boolean I showed in the second example. If you have multiple threads accessing the same variables, you’ll need to use synchronized methods or When you call start(), the Thread class actually creates the new JVM thread (which is separate from the calling thread), and calls run() from that new thread. util. Since they are not bound to be completed, they do not prevent the JVM from exiting. Android also supplies the java. Apr 10, 2017 · But a few of these tasks are background processing queues that take in new sub-tasks all the time and execute them in order. Java Threads Threads allows a program to operate more efficiently by doing multiple things at the same time. (You can use the thread pools that exist today in java. Threads can improve the performance and responsiveness of a program by allowing parallel execution of multiple tasks. How to run code in background thread after app is killed without Service? Nov 20, 2022 · We can extend java. By Extending Thread Class Create a class that extends Thread. For example: new Thread(new Runnable Oct 11, 2025 · Create Threads in Java We can create threads in java using two ways Thread-Creation Extending Thread Class Implementing a Runnable interface 1. Jul 28, 2025 · Learn everything about multithreading in Java, including core concepts, practical examples, common pitfalls, and when to use multithreading for optimal perfo… Jul 23, 2025 · 1. Aug 6, 2024 · This tutorial explains how to create and start threads in Java. & sends the process to the background, freeing up your terminal for other tasks. If you need to update the user interface from a new Thread, you need to synchronize with the main thread. sending an email, sms or notification, writing some log in file etc. Something like this: Creating a JPA session for background threads in Java requires careful management of your EntityManager and transactions to ensure thread safety and data integrity. I always forget that JFrame is nonmodal and creates those threads. Jul 25, 2022 · Coroutines are basically lightweight threads, they are used for doing background work. Syntax: public void run() { //statements } 1. com running tasks in the background can be essential for maintaining a responsive user interface in applications, parti In Spring Boot, you can run background tasks by leveraging Spring's asynchronous processing capabilities. There are several daemon threads in Java that run automatically, such as garbage collection (gc) and Jan 18, 2014 · Where are you running this code and what are the errors? An AsyncTask would be a good idea. Dec 20, 2012 · If you’re writing a desktop or Java Web Start program in Java using Swing, you might feel the need to run some stuff in the background by creating your own threads. Terminating your process terminates all your threads. What I mean is handler. Currently I have Jun 22, 2024 · Creatings threads in Java to run in the background is a common task for developers to handle asynchronous operations efficiently. Then we can create its object and call start() method to execute our custom java thread class Oct 20, 2023 · Like a skilled timekeeper, Java’s Timer class allows you to schedule tasks for future execution in a background thread. As you can see, Option 1 is probably best suited in NetBeans contains a thread pool org. For example, by using the ThreadPools and Executor classes. Apr 15, 2025 · Learn how to run a Java application as a background process, explore how to keep it running after closing the terminal session, and monitor it using logs. And Platform.