{"id":2843,"date":"2024-06-11T08:35:09","date_gmt":"2024-06-11T08:35:09","guid":{"rendered":"https:\/\/www.hirist.tech\/blog\/?p=2843"},"modified":"2025-12-29T12:31:28","modified_gmt":"2025-12-29T12:31:28","slug":"top-20-java-multithreading-interview-questions","status":"publish","type":"post","link":"https:\/\/www.hirist.tech\/blog\/top-20-java-multithreading-interview-questions\/","title":{"rendered":"Top 20+ Java Multithreading Interview Questions"},"content":{"rendered":"\n<p>Are you preparing for a job interview and worried about Java <strong>multithreading questions<\/strong>?&nbsp;We can understand why! Many Java developers find multithreading and concurrency topics challenging, especially during interviews.&nbsp;So, we have prepared this guide to cover the top 20+ most commonly asked <strong>Java multithreading interview questions<\/strong>, along with clear and concise answers.&nbsp;<\/p>\n\n\n\n<p>No matter what your experience level is, these questions will help you understand key concepts and confidently tackle your next interview.&nbsp;<\/p>\n\n\n\n<p>Let\u2019s boost your chances of landing that dream job!<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_65 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title \" >Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.hirist.tech\/blog\/top-20-java-multithreading-interview-questions\/#Java_Multithreading_Interview_Questions_for_Freshers\" title=\"Java Multithreading Interview Questions for Freshers\">Java Multithreading Interview Questions for Freshers<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.hirist.tech\/blog\/top-20-java-multithreading-interview-questions\/#Java_Multithreading_Interview_Questions_for_Experienced\" title=\"Java Multithreading Interview Questions for Experienced\">Java Multithreading Interview Questions for Experienced<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.hirist.tech\/blog\/top-20-java-multithreading-interview-questions\/#Multithreading_Scenario-Based_Questions\" title=\"Multithreading Scenario-Based Questions\">Multithreading Scenario-Based Questions<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.hirist.tech\/blog\/top-20-java-multithreading-interview-questions\/#Java_Multithreading_Coding_Interview_Questions\" title=\"Java Multithreading Coding Interview Questions\">Java Multithreading Coding Interview Questions<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.hirist.tech\/blog\/top-20-java-multithreading-interview-questions\/#Wrapping_Up\" title=\"Wrapping Up\">Wrapping Up<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Java_Multithreading_Interview_Questions_for_Freshers\"><\/span>Java Multithreading Interview Questions for Freshers<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Here are some commonly asked <strong>interview questions on multithreading Java<\/strong> and their answers.&nbsp;<\/p>\n\n\n\n<ol>\n<li><strong>What is multithreading in Java?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>Multithreading in Java is a feature that allows concurrent execution of two or more parts of a program. Each part is called a thread, and it helps in performing multiple tasks simultaneously, improving the performance of applications.<\/p>\n\n\n\n<ol start=\"2\">\n<li><strong>What is the difference between a process and a thread?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>A process is an independent program in execution, having its own memory space. A thread is a subset of a process and shares the same memory space as other threads within the same process, making it more lightweight.<\/p>\n\n\n\n<ol start=\"3\">\n<li><strong>What is the \u201csynchronized\u201d keyword used for?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>The \u201csynchronized\u201d keyword in Java is used to control the access of multiple threads to a shared resource. It ensures that only one thread can access the synchronized method or block at a time, preventing thread interference and consistency problems.<\/p>\n\n\n\n<ol start=\"4\">\n<li><strong>What is a deadlock?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>A deadlock is a situation where two or more threads are blocked forever, waiting for each other. This usually happens when two threads have a circular dependency on a pair of synchronized resources.<\/p>\n\n\n\n<ol start=\"5\">\n<li><strong>What are the different states of a thread in Java?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>A thread in Java can be in one of the following states:<\/p>\n\n\n\n<ul>\n<li><strong>New:<\/strong> The thread has been created but has not yet started.<\/li>\n\n\n\n<li><strong>Runnable:<\/strong> The thread is ready to run but waiting for CPU time.<\/li>\n\n\n\n<li><strong>Blocked:<\/strong> The thread is waiting for a monitor lock to enter a synchronized block\/method.<\/li>\n\n\n\n<li><strong>Waiting:<\/strong> The thread is waiting indefinitely for another thread to perform a specific action.<\/li>\n\n\n\n<li><strong>Timed Waiting:<\/strong> The thread is waiting for a specified amount of time.<\/li>\n\n\n\n<li><strong>Terminated:<\/strong> The thread has finished its execution.<\/li>\n<\/ul>\n\n\n\n<ol start=\"6\">\n<li><strong>What is the difference between wait() and sleep() methods in Java?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>The wait() method is used for inter-thread communication and releases the lock held by the thread, allowing other threads to acquire the lock. The sleep() method pauses the execution of the current thread for a specified time but does not release any locks.<\/p>\n\n\n\n<ol start=\"7\">\n<li><strong>What is the purpose of the \u201cvolatile\u201d keyword in Java?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>You may also come across <strong>Java concurrency interview questions<\/strong> like this one during the interview. Here\u2019s how you should answer it.&nbsp;<\/p>\n\n\n\n<p>The &#8220;volatile&#8221; keyword in Java is used to indicate that a variable will be changed by different threads. It ensures that the variable&#8217;s value is always read from and written to the main memory, making changes visible to all threads.&nbsp;<\/p>\n\n\n\n<p>However, it doesn&#8217;t guarantee atomicity. For that, synchronized methods or locks are needed.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Java_Multithreading_Interview_Questions_for_Experienced\"><\/span>Java Multithreading Interview Questions for Experienced<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Here are some important <strong>interview questions for multithreading in Java<\/strong> for experienced candidates.&nbsp;<\/p>\n\n\n\n<ol start=\"8\">\n<li><strong>What is the Callable interface, and how is it different from Runnable?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>The Callable interface, introduced in Java 5, is similar to Runnable but can return a result and throw a checked exception. It has a single method, call(), which returns a value of a generic type.&nbsp;<\/p>\n\n\n\n<p>In contrast, Runnable has a run() method that returns void and cannot throw checked exceptions.<\/p>\n\n\n\n<ol start=\"9\">\n<li><strong>Explain the concept of a thread pool and its benefits.<\/strong><\/li>\n<\/ol>\n\n\n\n<p>A thread pool is a collection of reusable threads that can be used to execute multiple tasks concurrently. The benefits of using a thread pool include,<\/p>\n\n\n\n<ul>\n<li>Improved performance through reduced overhead of thread creation and termination.<\/li>\n\n\n\n<li>Better resource management by limiting the number of active threads.<\/li>\n\n\n\n<li>The ability to manage and control task execution.<\/li>\n<\/ul>\n\n\n\n<ol start=\"10\">\n<li><strong>What are Future and FutureTask in Java?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>Future represents the result of an asynchronous computation. It provides methods to check if the computation is complete, wait for its completion, and retrieve the result.&nbsp;<\/p>\n\n\n\n<p>FutureTask is an implementation of Future that also implements Runnable, allowing it to be executed by a thread or a thread pool. It can be used to submit a task for execution and obtain a Future to monitor its progress and result.<\/p>\n\n\n\n<ol start=\"11\">\n<li><strong>What is the ForkJoinPool, and how does it work?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>ForkJoinPool is a special type of thread pool designed for parallel processing of tasks that can be broken down into smaller sub-tasks.&nbsp;<\/p>\n\n\n\n<p>It uses a work-stealing algorithm where idle threads can &#8220;steal&#8221; tasks from busy threads to ensure efficient use of resources. It is particularly useful for divide-and-conquer algorithms.<\/p>\n\n\n\n<ol start=\"12\">\n<li><strong>How do you handle thread safety in Java collections?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>Thread safety in <a href=\"https:\/\/www.hirist.tech\/blog\/top-20-java-collections-interview-questions-with-answers\/\" target=\"_blank\" rel=\"noreferrer noopener\">Java collections<\/a> can be handled using synchronized collections from the Collections class (e.g., Collections.synchronizedList()), concurrent collections from the java.util.concurrent package (e.g., ConcurrentHashMap, CopyOnWriteArrayList), and by using explicit synchronization blocks or locks around critical sections.<\/p>\n\n\n\n<ol start=\"13\">\n<li><strong>What are the key features of Java 8 that enhance multithreading?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>The interviewer may also ask <strong>multithreading interview questions Java 8<\/strong>. You can expect this question.&nbsp;<\/p>\n\n\n\n<p><a href=\"https:\/\/www.hirist.tech\/blog\/top-30-java-8-interview-questions-with-answers\/\" target=\"_blank\" rel=\"noreferrer noopener\">Java 8<\/a> introduced several features to enhance multithreading, including lambda expressions and the java.util.concurrent package enhancements, and the CompletableFuture class.&nbsp;<\/p>\n\n\n\n<p>Lambda expressions allow for more concise and expressive code when working with threads. The enhancements in the java.util.concurrent package provide more efficient ways to manage and control concurrent tasks.&nbsp;<\/p>\n\n\n\n<p>The CompletableFuture class enables asynchronous programming and simplifies handling asynchronous results.<\/p>\n\n\n\n<ol start=\"14\">\n<li><strong>Can you share an experience where you had to resolve a difficult multithreading issue in a project?<\/strong><\/li>\n<\/ol>\n\n\n\n<p>This is one of the most commonly-asked <strong>Java multithreading interview questions for 10 years experience<\/strong>d candidates.&nbsp;<\/p>\n\n\n\n<p><strong><em>\u201c<\/em><\/strong><em>Once, in a project, multiple threads were accessing a shared resource simultaneously, causing data inconsistencies. To fix it, I applied synchronization techniques and used concurrent data structures like ConcurrentHashMap. After debugging and testing, I resolved the issue, ensuring the application&#8217;s reliability.\u201d<\/em><\/p>\n\n\n\n<pre class=\"wp-block-verse\"><strong>Also Read - <a href=\"https:\/\/www.hirist.tech\/blog\/top-20-hashmap-interview-questions-with-answers\/\" target=\"_blank\" rel=\"noreferrer noopener\">Top 20+ HashMap Interview Questions With Answers<\/a><\/strong><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Multithreading_Scenario-Based_Questions\"><\/span>Multithreading Scenario-Based Questions<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>You may also encounter a few scenario-based <strong>multithreading questions<\/strong> on Java. Here are some common questions and their answers.&nbsp;<\/p>\n\n\n\n<ol start=\"15\">\n<li><strong>Suppose you need to perform a task asynchronously in your application. How would you achieve this using Java?<\/strong><\/li>\n<\/ol>\n\n\n\n<p><em>\u201cI would use the Thread class or Runnable interface to create a separate thread for the asynchronous task. Alternatively, I could use the ExecutorService from the java.util.concurrent package for more control over thread management.\u201d<\/em><\/p>\n\n\n\n<ol start=\"16\">\n<li><strong>What would you do if you wanted to wait for a specific event to occur in one thread before proceeding with another thread?<\/strong><\/li>\n<\/ol>\n\n\n\n<p><em>\u201cI would use synchronization tools such as CountDownLatch or CyclicBarrier to coordinate the threads. These tools allow one or more threads to wait until a specific event or condition occurs before proceeding.\u201d<\/em><\/p>\n\n\n\n<ol start=\"17\">\n<li><strong>You have a long-running task that might block other operations. How would you prevent this from affecting the overall performance of the application?<\/strong><\/li>\n<\/ol>\n\n\n\n<p><em>\u201cI would execute the long-running task asynchronously using a separate thread to prevent blocking other operations. This can be achieved using techniques such as thread pooling or the CompletableFuture class in Java 8.\u201d<\/em><\/p>\n\n\n\n<ol start=\"18\">\n<li><strong>You need to perform a set of independent tasks concurrently and then combine their results. How would you approach this problem?<\/strong><\/li>\n<\/ol>\n\n\n\n<p><em>\u201cI would use the ExecutorService framework to execute the independent tasks concurrently and then use Future objects to obtain their results. Once all tasks are completed, I would combine their results as needed.\u201d<\/em><\/p>\n\n\n\n<ol start=\"19\">\n<li><strong>You have a producer-consumer scenario where multiple producer threads are producing data, and multiple consumer threads are consuming it. How would you implement this scenario?<\/strong><\/li>\n<\/ol>\n\n\n\n<p><em>\u201cI would use a thread-safe <a href=\"https:\/\/www.hirist.tech\/blog\/top-25-java-data-structures-interview-questions-with-answers\/\">data structure<\/a> such as BlockingQueue to store the data produced by the producer threads. The consumer threads would then retrieve and process the data from the queue, ensuring thread safety and proper synchronization.\u201d<\/em><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Java_Multithreading_Coding_Interview_Questions\"><\/span>Java Multithreading Coding Interview Questions<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Here are some important coding <strong>Java thread interview questions<\/strong> and their answers.&nbsp;<\/p>\n\n\n\n<ol start=\"20\">\n<li><strong>Write a Java program to create a simple thread by extending the Thread class.<\/strong><\/li>\n<\/ol>\n\n\n\n<p>public class MyThread extends Thread {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;public void run() {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println(&#8220;MyThread is running&#8230;&#8221;);<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;public static void main(String[] args) {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;MyThread thread = new MyThread();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;thread.start();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>}<\/p>\n\n\n\n<ol start=\"21\">\n<li><strong>Write a Java program to create a thread by implementing the Runnable interface.<\/strong><\/li>\n<\/ol>\n\n\n\n<p>public class MyRunnable implements Runnable {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;public void run() {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println(&#8220;MyRunnable is running&#8230;&#8221;);<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;public static void main(String[] args) {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Thread thread = new Thread(new MyRunnable());<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;thread.start();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>}<\/p>\n\n\n\n<ol start=\"22\">\n<li><strong>Write a Java program to demonstrate synchronization using the synchronized keyword.<\/strong><\/li>\n<\/ol>\n\n\n\n<p>public class SynchronizationExample {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;private int count = 0;<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;public synchronized void increment() {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;count++;<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;public static void main(String[] args) throws InterruptedException {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;SynchronizationExample obj = new SynchronizationExample();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Thread thread1 = new Thread(() -&gt; {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for (int i = 0; i &lt; 1000; i++) {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;obj.increment();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;});<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Thread thread2 = new Thread(() -&gt; {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;for (int i = 0; i &lt; 1000; i++) {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;obj.increment();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;});<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;thread1.start();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;thread2.start();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;thread1.join();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;thread2.join();<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println(&#8220;Count: &#8221; + obj.count);<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>}<\/p>\n\n\n\n<ol start=\"23\">\n<li><strong>Write a Java program to demonstrate how to use the CompletableFuture class for asynchronous programming.<\/strong><\/li>\n<\/ol>\n\n\n\n<p>import java.util.concurrent.CompletableFuture;<\/p>\n\n\n\n<p>import java.util.concurrent.ExecutionException;<\/p>\n\n\n\n<p>public class CompletableFutureExample {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;public static void main(String[] args) throws ExecutionException, InterruptedException {<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CompletableFuture&lt;String&gt; future = CompletableFuture.supplyAsync(() -&gt; &#8220;Hello&#8221;);<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CompletableFuture&lt;String&gt; completedFuture = future.thenApply(result -&gt; result + &#8221; World&#8221;);<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;System.out.println(completedFuture.get());<\/p>\n\n\n\n<p>&nbsp;&nbsp;&nbsp;&nbsp;}<\/p>\n\n\n\n<p>}<\/p>\n\n\n\n<pre class=\"wp-block-verse\"><strong>Also Read - <a href=\"https:\/\/www.hirist.tech\/blog\/top-25-exception-handling-questions-in-java-interview\/\" target=\"_blank\" rel=\"noreferrer noopener\">Top 25 Exception Handling Questions In Java Interview<\/a><\/strong><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Wrapping_Up\"><\/span>Wrapping Up<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>With these 15+ <strong>Java multithreading interview questions<\/strong> and answers, you now have a strong foundation to tackle multithreading-related queries confidently.&nbsp;Looking for exciting <a href=\"https:\/\/www.hirist.tech\/k\/multithreading-jobs.html?ref=blog\" target=\"_blank\" rel=\"noreferrer noopener\">java multithreading job opportunities<\/a> in the IT sector? Visit <a href=\"https:\/\/www.hirist.tech\/\" target=\"_blank\" rel=\"noreferrer noopener\">Hirist<\/a> to find the latest job openings at top IT companies in India. Simply install the Hirist app on your phone and apply for jobs on the go.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Are you preparing for a job interview and worried about Java multithreading questions?&nbsp;We can understand&hellip;<\/p>\n","protected":false},"author":1,"featured_media":2856,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22,29,19],"tags":[32,34,35,33],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.5 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Top 15+ Java Multithreading Interview Questions for 2026 | Hirist<\/title>\n<meta name=\"description\" content=\"Find the 20+ most commonly asked Java multithreading interview questions and their answers in our guide. 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