Spring@Transactional on@bean声明而不是类实现

Question

我想从我的Spring@configuration类中配置“事务性”bean，而不是用@transactional注释类实现本身。

/** This class has no Spring dependency... */
// @Transactional <- which means I can't use this here
public final class ComplexComponentImpl implements ComplexComponent {

    private SomeRepository repo;

    public ComplexComponentImpl(SomeRepository repository) { this.repo = repository }

    public void saveEntities(SomeEntity e1, SomeEntity e2) {
        repo.save(e1);
        throw new IllegalStateException("Make the transaction fail");
    }

@Configuration
@EnableTransactionManagement
public class ComplexComponentConfig {

    @Bean
    @Transactional // <- Make the bean transactional here
    public ComplexComponent complexComponent() {
        return new ComplexComponentImpl(repository());
    }

    // ...
}

问题：是否可以从@configuration类声明@bean的事务性，或者考虑到上面的约束，是否有其他选择？

Answer 1

发现了一些内置的东西，这是@mecon和@erik gillespie的答案的总和，只有有限的样板。

Spring已经提供了TransactionProxyFactoryBean，它只是在任何对象上设置一个事务代理。许多设置都可以重构为某个实用程序方法：

@Configuration
@EnableTransactionManagement
public class ComplexComponentConfig {

    /** NOT A @Bean, this object will be wrapped with a transactional proxy */
    public ComplexComponent complexComponentImpl() {
        return new ComplexComponentImpl(repository());
    }

    @Bean
    public ComplexComponent complexComponent() {
        TransactionProxyFactoryBean proxy = new TransactionProxyFactoryBean();

        // Inject transaction manager here
        proxy.setTransactionManager(txManager());

        // Define wich object instance is to be proxied (your bean)
        proxy.setTarget(complexComponentImpl());

        // Programmatically setup transaction attributes
        Properties transactionAttributes = new Properties();
        transactionAttributes.put("*", "PROPAGATION_REQUIRED");
        proxy.setTransactionAttributes(transactionAttributes);

        // Finish FactoryBean setup
        proxy.afterPropertiesSet();
        return (ComplexComponent) proxy.getObject;
    }

// ...
}