Spring Boot | Database Access | Using Declarative Transactions

Using Declarative Transactions

Applying @Transactional to a method makes the method invocation a transaction boundary.
If a RuntimeException or subclass is thrown within the transaction boundary, the transaction is rolled back.
An Exception or subclass does not trigger rollback by default.
To roll back when an Exception occurs, configure @Transactional(rollbackFor = Exception.class).

Writing the Code

src/main/java/sample/springboot/jpa/MyService.java

package sample.springboot.jpa;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.transaction.annotation.Transactional;

@Component
public class MyService {

    @Autowired
    private HogeRepository repository;

    public void save(String value) {
        Hoge hoge = new Hoge(value);
        this.repository.save(hoge);
    }

    public void saveAndThrowRuntimeException(String value) {
        this.save(value);
        throw new RuntimeException("test");
    }

    @Transactional
    public void saveAndThrowRuntimeExceptionWithTransactional(String value) {
        this.saveAndThrowRuntimeException(value);
    }

    @Transactional
    public void saveAndThrowExceptionWithTransactional(String value) throws Exception {
        this.save(value);
        throw new Exception("test");
    }

    public void show() {
        this.repository.findAll().forEach(System.out::println);
    }
}

src/main/java/sample/springboot/jpa/Main.java

package sample.springboot;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;

import sample.springboot.jpa.MyService;

@SpringBootApplication
public class Main {

    public static void main(String[] args) throws Exception {
        try (ConfigurableApplicationContext ctx = SpringApplication.run(Main.class, args)) {
            MyService s = ctx.getBean(MyService.class);

            s.save("normal");

            try {
                s.saveAndThrowRuntimeException("runtime exception without @Transactional");
            } catch (Exception e) {}

            try {
                s.saveAndThrowRuntimeExceptionWithTransactional("runtime exception with @Transactional");
            } catch (Exception e) {}

            try {
                s.saveAndThrowExceptionWithTransactional("exception with @Transactional");
            } catch (Exception e) {}

            s.show();
        }
    }
}

Result

Hoge [id=1, value=normal]
Hoge [id=2, value=runtime exception without @Transactional]
Hoge [id=4, value=exception with @Transactional]