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Showing posts with label Java Multithreading Tutorial. Show all posts
Showing posts with label Java Multithreading Tutorial. Show all posts

Explain about CyclicBarrier in Java

1:28 AM
How to use CyclicBarrier in Java - Concurrency Tutorial This is the second part of my concurrency tutorial, in the first part, you have learned how to use CountDownLatch and in this part, you will learn how to use CyclicBarrier class in Java. CyclicBarrier is another concurrency utility introduced in Java 5 which is used when a number of threads (also known as parties) want to wait for each other at a common point, also known as the barrier before starting processing again. Its similar to CountDownLatch but instead of calling countDown() each thread calls await() and when last thread calls await() which signals that it has reached the barrier, all thread started processing again, also known as a barrier is broken. You can use CyclicBarrier wherever you want to use CountDownLatch, but the opposite is not possible because you can not reuse the latch once the count reaches to zero. Some of the common usages of CyclicBarrier is in writing a unit test for concurrent program, to simulate...
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Explain about CountDowaLatch

1:18 AM
Explain about CountDowaLatch CountDowaLatch is a high-level synchronization utility which is used to prevent a particular thread to start processing until all threads are ready. This is achieved by a countdown. The thread, which needs to wait for starts with a counter, each thread them make the count down by 1 when they become ready, once the last thread call countDown() method, then the latch is broken and the thread waiting with counter starts running. CountDownLatch is a useful synchronizer and used heavily in multi-threaded testing. You can use this class to simulate truly concurrent behavior i.e. trying to access something at the same time once every thread is ready. Worth noting is that CountDownLatch starts with a fixed number of counts which cannot be changed later, though this restriction is re-mediated in Java 7 by introducing a similar but flexible concurrency utility called Phaser. There is another similar utility called CyclicBarrier, which can also be used in this si...
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Producer Consumer problem Solution using BlockingQueue in Java Thread

1:14 AM
Producer Consumer Solution using BlockingQueue in Java Thread Producer Consumer problem is one of the classic multi-threading problems in computer science and the multi-threading world. It's tricky because it involves inter-thread communication, but it's important because most of the multi-threading problems fits into this category. There are many ways to solve producer consumer problem in Java e.g. you can solve this by using wait() and notify() method, as discussed here, or you can use the Semaphore to solve this problem. In this article, you will learn a third way to solve the producer-consumer problem by using the BlockingQueue in Java. It is arguably the simplest way to solve this problem in any programming language because blocking queue data structure not only provides storage but also provides flow control and thread-safety, which makes the code really simple. Brian Goetz has also explained this key class and pattern in his classic Java Concurrency in Practice book,...
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Sleep vs yield in Java

1:11 AM
Sleep vs yield in Java Sleep and yield are two methods which are used to get CPU back from Thread to Thread Scheduler in java but they are completely different than each other. The major difference between Sleep vs yield is that sleep is more reliable than yield and it's advised to use sleep(1) instead of yield to relinquish CPU in multi-threaded Java application to give an opportunity to other threads to execute. In this Java tutorial, we will what are differences between yield and sleep in Java. But before seeing difference between sleep and Yield let's see some similarities between yield and sleep in Java Similarities between Sleep and yield in Java  Here are some common things between sleep and yield method in Java programming : 1) Both yield and sleep are declared on java.lang.Thread class. 2) Both sleep() and yield() are static methods and operate on current thread. It doesn't matter which thread's object you used to call this method, both these meth...
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Explain wait(), notify() and notifyAll() in Java Thread?

1:08 AM
If you ask me one concept in Java which is so obvious yet most misunderstood, I would say the wait(), notify() and notifyAll() methods. They are quite obvious because they are the one of the three methods of total 9 methods from java.lang.Object but if you ask when to use the wait(), notify() and notfiyAll() in Java, not many Java developer can answer with surety. The number will go down dramatically if you ask them to solve the producer-consumer problem using wait() and notify(). Many will use if block instead of while loop, many others will get confused on which object they should call wait() and notify()method? Some of them even succeed in creating livelock, deadlock, and other multithreading issues. That's why it's become very important to know as much as possible about these three methods. In this article, I am going to share some practical tips and points about wait(), notify() and notifyAll() in Java. Two books, which helped me a lot while understanding this core c...
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How to use Multiple Threads in Java with Example

1:06 AM
you need to first define the task which will be executed by those threads. In order to create those task, you can either use Runnable or Callable interface. If you are just learning Java chose Runnable, it's simpler one, but if you are familiar with Java multithreading and want to leverage additional features offered by Callable e.g. it can throw an exception and it can also return value, then go ahead and use Callable. Once you have task ready, you need to create an instance of Thread class. You can create as many instances as you want, but beware don't create too many Thread instances in Java because both JVM and Operating system has a limit on how many threads you can create in Java. Crossing that limit will result in java.lang.OutOfmemoryError: could not create a native thread. For the purpose of this example, creating just three threads are enough. Let's assume we create threads T1, T2, and T3. While creating we pass them an instance of your Task class, which extend...
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Difference between Daemon Thread vs User Thread in Java with example?

1:01 AM
Difference between Daemon Thread vs User Thread in Java? A thread is used to perform parallel execution  in Jaa e.g. while rendering screen your program is also downloading the data from the internet in the background. There are two types of threads in Java, user thread and daemon thread, both of which can use to implement parallel processing in Java depending upon priority and importance of the task. The main difference between a user thread and a daemon thread is that your Java program will not finish execution until one of the user thread is live. JVM will wait for all active user threads to finish their execution before it shutdown itself. On the other hand, a daemon thread doesn't get that preference, JVM will exit and close the Java program even if there is a daemon thread running in the background. They are treated as low priority threads in Java, that's why they are more suitable for non-critical background jobs. In this article, we will learn some key difference be...
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