👀 Views: 321 💬 Answers: 1 📅 Created: 2025-06-06

java spring-boot jpa testing multithreading Java

I've spent hours debugging this and I'm relatively new to this, so bear with me..... I am experiencing flaky test failures when running my Spring Boot application with JPA in a multi-threaded environment. The tests occasionally fail due to `javax.persistence.TransactionRequiredException`, which indicates that a transaction is required but not active. Here’s a code snippet of the relevant service method: ```java @Service public class UserService { @Autowired private UserRepository userRepository; @Transactional public User createUser(String username) { User user = new User(username); return userRepository.save(user); } } ``` In my test, I'm trying to create multiple users in parallel using JUnit and a thread pool: ```java @Test public void testConcurrentUserCreation() throws InterruptedException { ExecutorService executor = Executors.newFixedThreadPool(10); List<Future<User>> futures = new ArrayList<>(); for (int i = 0; i < 20; i++) { final String username = "user" + i; futures.add(executor.submit(() -> userService.createUser(username))); } executor.shutdown(); executor.awaitTermination(1, TimeUnit.MINUTES); for (Future<User> future : futures) { try { future.get(); } catch (ExecutionException e) { e.printStackTrace(); // This shows the TransactionRequiredException occasionally } } } ``` I've tried to ensure that the `@Transactional` annotation is correctly placed, and I even set the isolation level to `Isolation.READ_COMMITTED` in my application properties: ```properties spring.jpa.properties.hibernate.connection.provider_class=org.hibernate.connection.C3P0ConnectionProvider spring.jpa.hibernate.ddl-auto=update spring.jpa.properties.hibernate.transaction.jta.platform=org.hibernate.service.jta.platform.internal.NoJtaPlatform ``` Despite these efforts, the `TransactionRequiredException` still surfaces sporadically. It appears that the concurrent execution may lead to scenarios where the transaction context is not properly propagated across threads. Could someone provide insights or suggestions on how to tackle this issue? Are there best practices for managing transactions in a multi-threaded environment with Spring and JPA? What's the best practice here? This issue appeared after updating to Java 3.11. Am I approaching this the right way? I'm coming from a different tech stack and learning Java. Has anyone else encountered this? The stack includes Java and several other technologies.