In Spring, transactions are usually managed with the @Transactional annotation.

A transaction makes sure that a group of database operations is either:

• all succeed, or
• all fail and roll back

This is important when one business operation changes multiple records or tables.

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1. Enable Transaction Management

If you are using Spring Boot with Spring Data JPA, transaction management is usually configured automatically.

In most Spring Boot applications, you do not need to manually enable it.

If you are using plain Spring configuration, you may need:

import org.springframework.context.annotation.Configuration;
import org.springframework.transaction.annotation.EnableTransactionManagement;

@Configuration
@EnableTransactionManagement
public class TransactionConfig {
}

With Spring Boot, this is normally unnecessary.

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2. Use @Transactional on Service Methods

The most common place to put transactions is the service layer, not the controller or repository.

Example:

package com.example.app.order;

import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service
public class OrderService {

    private final OrderRepository orderRepository;
    private final PaymentRepository paymentRepository;

    public OrderService(
            OrderRepository orderRepository,
            PaymentRepository paymentRepository
    ) {
        this.orderRepository = orderRepository;
        this.paymentRepository = paymentRepository;
    }

    @Transactional
    public void placeOrder(Order order, Payment payment) {
        orderRepository.save(order);
        paymentRepository.save(payment);
    }
}

If paymentRepository.save(payment) fails, Spring rolls back the earlier orderRepository.save(order) operation.

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3. Use readOnly = true for Query Methods

For methods that only read data, use:

@Transactional(readOnly = true)

Example:

package com.example.app.order;

import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.List;

@Service
public class OrderQueryService {

    private final OrderRepository orderRepository;

    public OrderQueryService(OrderRepository orderRepository) {
        this.orderRepository = orderRepository;
    }

    @Transactional(readOnly = true)
    public List<Order> findAllOrders() {
        return orderRepository.findAll();
    }
}

readOnly = true can help performance and communicates that the method should not modify data.

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4. Rollback Behavior

By default, Spring rolls back a transaction for:

• RuntimeException
• Error

By default, Spring does not roll back for checked exceptions.

Example:

@Transactional
public void updateOrder() {
    throw new IllegalStateException("Something failed");
}

This transaction rolls back because IllegalStateException is a runtime exception.

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5. Roll Back for Checked Exceptions

If you want rollback for a checked exception, specify rollbackFor.

@Transactional(rollbackFor = Exception.class)
public void importOrders() throws Exception {
    // database changes
    throw new Exception("Import failed");
}

You can also target a specific exception:

@Transactional(rollbackFor = OrderImportException.class)
public void importOrders() throws OrderImportException {
    // database changes
    throw new OrderImportException("Import failed");
}

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6. Avoid Catching Exceptions Without Rethrowing

This can prevent rollback:

@Transactional
public void placeOrder(Order order) {
    try {
        orderRepository.save(order);
        paymentService.charge(order);
    } catch (Exception ex) {
        // Bad if you swallow the exception
    }
}

If the exception is caught and not rethrown, Spring may think the method completed successfully and commit the transaction.

Prefer:

@Transactional
public void placeOrder(Order order) {
    try {
        orderRepository.save(order);
        paymentService.charge(order);
    } catch (Exception ex) {
        throw new OrderProcessingException("Could not place order", ex);
    }
}

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7. Transaction Boundaries Should Match Business Operations

A transaction should usually wrap one complete business action.

Good examples:

@Transactional
public void transferMoney(Long fromAccountId, Long toAccountId, BigDecimal amount) {
    debitAccount(fromAccountId, amount);
    creditAccount(toAccountId, amount);
}

@Transactional
public void registerUser(RegisterUserRequest request) {
    createUser(request);
    createDefaultSettings(request);
    sendWelcomeEvent(request);
}

Avoid making transactions too large, especially if they include slow external calls.

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8. Be Careful with External API Calls

Avoid doing slow network calls inside a database transaction when possible.

Less ideal:

@Transactional
public void placeOrder(Order order) {
    orderRepository.save(order);
    paymentGateway.charge(order); // external network call inside transaction
    order.setStatus(OrderStatus.PAID);
}

Better pattern:

@Transactional
public Order createPendingOrder(Order order) {
    order.setStatus(OrderStatus.PENDING_PAYMENT);
    return orderRepository.save(order);
}

@Transactional
public void markOrderPaid(Long orderId) {
    Order order = orderRepository.findById(orderId)
            .orElseThrow();

    order.setStatus(OrderStatus.PAID);
}

Then call the payment gateway between those operations.

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9. Common @Transactional Options

@Transactional(
        readOnly = false,
        rollbackFor = Exception.class,
        timeout = 10
)
public void processOrder() {
    // database work
}

Common options:

Option	Meaning
readOnly	Marks the transaction as read-only
rollbackFor	Exceptions that should trigger rollback
noRollbackFor	Exceptions that should not trigger rollback
timeout	Maximum transaction duration in seconds
propagation	How this method joins or creates transactions
isolation	How isolated this transaction is from other transactions

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10. Propagation Basics

Propagation controls what happens if a transactional method calls another transactional method.

The default is:

Propagation.REQUIRED

That means:

• join the existing transaction if one exists
• otherwise create a new transaction

Example:

@Transactional
public void checkout() {
    reserveInventory();
    chargePayment();
}

If reserveInventory() and chargePayment() are also transactional with default propagation, they participate in the same transaction.

Common propagation values:

Propagation	Meaning
REQUIRED	Use current transaction or create one
REQUIRES_NEW	Always start a new transaction
MANDATORY	Must already have a transaction
SUPPORTS	Use a transaction if one exists
NOT_SUPPORTED	Run without a transaction
NEVER	Fail if a transaction exists
NESTED	Use a nested transaction if supported

Example using a separate transaction for audit logging:

@Transactional(propagation = Propagation.REQUIRES_NEW)
public void saveAuditLog(String message) {
    auditLogRepository.save(new AuditLog(message));
}

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11. Isolation Basics

Isolation controls how much one transaction can see changes from another transaction.

Example:

@Transactional(isolation = Isolation.READ_COMMITTED)
public void processPayment() {
    // database work
}

Common isolation levels:

Isolation	Meaning
DEFAULT	Use the database default
READ_UNCOMMITTED	May read uncommitted changes
READ_COMMITTED	Only read committed data
REPEATABLE_READ	Same row read twice stays consistent
SERIALIZABLE	Strongest isolation, lowest concurrency

Most applications use the database by default unless there is a specific consistency problem.

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12. Important Limitation: Self-Invocation

Spring transactions are usually applied through proxies.

That means this may not start a transaction as expected:

@Service
public class UserService {

    public void outerMethod() {
        innerMethod();
    }

    @Transactional
    public void innerMethod() {
        // database work
    }
}

Because innerMethod() is called from the same class, the call may bypass Spring’s transactional proxy.

Prefer calling transactional methods from another Spring bean, or put @Transactional on the outer method:

@Service
public class UserService {

    @Transactional
    public void outerMethod() {
        innerMethod();
    }

    public void innerMethod() {
        // database work
    }
}

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13. Recommended Structure

A typical Spring application uses transactions like this:

Controller
    ↓
Service  ← @Transactional here
    ↓
Repository
    ↓
Database

Example:

@RestController
public class OrderController {

    private final OrderService orderService;

    public OrderController(OrderService orderService) {
        this.orderService = orderService;
    }

    @PostMapping("/orders")
    public void createOrder(@RequestBody Order order) {
        orderService.createOrder(order);
    }
}

@Service
public class OrderService {

    private final OrderRepository orderRepository;

    public OrderService(OrderRepository orderRepository) {
        this.orderRepository = orderRepository;
    }

    @Transactional
    public void createOrder(Order order) {
        orderRepository.save(order);
    }
}

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Quick Rules

Use these defaults for most Spring applications:

1. Put @Transactional on service methods.
2. Use @Transactional(readOnly = true) for query methods.
3. Use @Transactional for create, update, and delete methods.
4. Do not swallow exceptions inside transactional methods.
5. Use rollbackFor if you need rollback for checked exceptions.
6. Keep transactions short.
7. Avoid slow external API calls inside transactions.
8. Be aware that self-invocation can bypass transactional behavior.

For most Spring Boot + Spring Data JPA applications, this is enough:

@Service
public class UserService {

    private final UserRepository userRepository;

    public UserService(UserRepository userRepository) {
        this.userRepository = userRepository;
    }

    @Transactional(readOnly = true)
    public List<User> findUsers() {
        return userRepository.findAll();
    }

    @Transactional
    public User createUser(User user) {
        return userRepository.save(user);
    }
}