Spring事务管理零基础入门

import lombok.Data;
import javax.persistence.*;
@Data
@Entity
public class User {
    @Id
    @GeneratedValue
    private Integer id;
    private String name;
    private double money;
}

package com.dily.study.work.service;
import com.dily.study.work.entity.User;
import com.dily.study.work.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class UserService {
    @Autowired // 使用jpa
    private UserRepository userRepository;
    
    public void out(String fromName, int money) {
        User user = userRepository.findByName(fromName);
        user.setMoney(user.getMoney() - money);
        userRepository.save(user);
    }
    
    public void in(String toName, int money) {
        User user = userRepository.findByName(toName);
        user.setMoney(user.getMoney() + money);
        userRepository.save(user);
    }
     
    @Transactional
    public void transfer(String fromName, String toName, int money) {
        out(fromName, money);
        if (true) throw new RuntimeException("出错了");
        in(toName, money);
    }
    
    public void transfer(String fromName, String toName, int money) {
        out(fromName, money);
        if (true) throw new RuntimeException("出错了");
        in(toName, money);
    }
}

// 在 UserService 中注入自己，因为如果内部调用自己的方法，事务注解不生效。
@Autowired
private UserService userService;

@Transactional
public void laoda(String fromName, String toName, int money) {
    userService.out(fromName, money);
    if (true) throw new RuntimeException("出错了");
    userService.xiaodi(toName,money);
}

@Transactional(propagation = Propagation.MANDATORY)
public void xiaodi(String toName, int money) {
    if (true) throw new RuntimeException("出错了");
    userService.in(toName, money);
}