使用Java编程和springboot框架,连接mysql数据库（奖品表名为a,活动表名为b,两者关联的表为c）实现 1.创建活动并关联奖品，一个活动必须关联8个奖品，总概率为100% 2.修改活动 活动名称不能重复 并更新关联奖品，给出具体程序，包括给出相应的controller层，service层，service实现类，dao层及mapper.xml文件

好的，首先需要创建一个Spring Boot项目，并且添加相关依赖，包括 Spring Boot、MyBatis、MySQL Connector 等。

接下来，我们需要在 MySQL 中创建两个表，分别为 a 和 b，以及一个关联表 c。表结构如下：

-- 奖品表 a
CREATE TABLE `a` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) DEFAULT NULL,
  `probability` int(11) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4;

-- 活动表 b
CREATE TABLE `b` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4;

-- 关联表 c
CREATE TABLE `c` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `aid` int(11) NOT NULL,
  `bid` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `idx_aid_bid` (`aid`,`bid`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4;

然后，我们需要定义实体类 Prize 和 Activity，以及它们的关联类 PrizeActivity。

// Prize.java
public class Prize {
    private Integer id;
    private String name;
    private Integer probability;
    // 省略 getter 和 setter
}

// Activity.java
public class Activity {
    private Integer id;
    private String name;
    private List<Prize> prizes;
    // 省略 getter 和 setter
}

// PrizeActivity.java
public class PrizeActivity {
    private Integer id;
    private Integer aid;
    private Integer bid;
    // 省略 getter 和 setter
}

在 DAO 层中，我们需要定义三个接口：PrizeMapper、ActivityMapper 和 PrizeActivityMapper。

// PrizeMapper.java
@Mapper
public interface PrizeMapper {
    @Select("SELECT * FROM a")
    List<Prize> getAllPrizes();
}

// ActivityMapper.java
@Mapper
public interface ActivityMapper {
    @Select("SELECT * FROM b WHERE id = #{id}")
    Activity getActivityById(Integer id);

    @Select("SELECT * FROM b WHERE name = #{name}")
    Activity getActivityByName(String name);

    @Insert("INSERT INTO b (name) VALUES (#{name})")
    @Options(useGeneratedKeys = true, keyProperty = "id")
    int createActivity(Activity activity);

    @Update("UPDATE b SET name = #{name} WHERE id = #{id}")
    void updateActivity(Activity activity);
}

// PrizeActivityMapper.java
@Mapper
public interface PrizeActivityMapper {
    @Insert("INSERT INTO c (aid, bid) VALUES (#{aid}, #{bid})")
    void createPrizeActivity(PrizeActivity prizeActivity);

    @Delete("DELETE FROM c WHERE bid = #{bid}")
    void deletePrizeActivityByActivityId(Integer bid);
}

接下来，我们需要在 Service 层中定义三个接口：PrizeService、ActivityService 和 PrizeActivityService，并且实现它们的方法。

// PrizeService.java
public interface PrizeService {
    List<Prize> getAllPrizes();
}

// ActivityService.java
public interface ActivityService {
    Activity getActivityById(Integer id);

    Activity getActivityByName(String name);

    Activity createActivity(Activity activity);

    void updateActivity(Activity activity);
}

// PrizeActivityService.java
public interface PrizeActivityService {
    void createPrizeActivity(Integer aid, Integer bid);

    void deletePrizeActivityByActivityId(Integer bid);
}

// PrizeServiceImpl.java
@Service
public class PrizeServiceImpl implements PrizeService {
    private final PrizeMapper prizeMapper;

    public PrizeServiceImpl(PrizeMapper prizeMapper) {
        this.prizeMapper = prizeMapper;
    }

    @Override
    public List<Prize> getAllPrizes() {
        return prizeMapper.getAllPrizes();
    }
}

// ActivityServiceImpl.java
@Service
public class ActivityServiceImpl implements ActivityService {
    private final ActivityMapper activityMapper;
    private final PrizeActivityService prizeActivityService;

    public ActivityServiceImpl(ActivityMapper activityMapper, PrizeActivityService prizeActivityService) {
        this.activityMapper = activityMapper;
        this.prizeActivityService = prizeActivityService;
    }

    @Override
    public Activity getActivityById(Integer id) {
        return activityMapper.getActivityById(id);
    }

    @Override
    public Activity getActivityByName(String name) {
        return activityMapper.getActivityByName(name);
    }

    @Override
    public Activity createActivity(Activity activity) {
        activityMapper.createActivity(activity);
        for (Prize prize : activity.getPrizes()) {
            prizeActivityService.createPrizeActivity(prize.getId(), activity.getId());
        }
        return activity;
    }

    @Override
    public void updateActivity(Activity activity) {
        activityMapper.updateActivity(activity);
        prizeActivityService.deletePrizeActivityByActivityId(activity.getId());
        for (Prize prize : activity.getPrizes()) {
            prizeActivityService.createPrizeActivity(prize.getId(), activity.getId());
        }
    }
}

// PrizeActivityServiceImpl.java
@Service
public class PrizeActivityServiceImpl implements PrizeActivityService {
    private final PrizeActivityMapper prizeActivityMapper;

    public PrizeActivityServiceImpl(PrizeActivityMapper prizeActivityMapper) {
        this.prizeActivityMapper = prizeActivityMapper;
    }

    @Override
    public void createPrizeActivity(Integer aid, Integer bid) {
        PrizeActivity prizeActivity = new PrizeActivity();
        prizeActivity.setAid(aid);
        prizeActivity.setBid(bid);
        prizeActivityMapper.createPrizeActivity(prizeActivity);
    }

    @Override
    public void deletePrizeActivityByActivityId(Integer bid) {
        prizeActivityMapper.deletePrizeActivityByActivityId(bid);
    }
}

最后，在 Controller 层中定义 ActivityController，并且注入 ActivityService。

@RestController
@RequestMapping("/activity")
public class ActivityController {
    private final ActivityService activityService;

    public ActivityController(ActivityService activityService) {
        this.activityService = activityService;
    }

    @GetMapping("/{id}")
    public Activity getActivityById(@PathVariable("id") Integer id) {
        return activityService.getActivityById(id);
    }

    @GetMapping("/name/{name}")
    public Activity getActivityByName(@PathVariable("name") String name) {
        return activityService.getActivityByName(name);
    }

    @PostMapping("")
    public Activity createActivity(@RequestBody Activity activity) {
        return activityService.createActivity(activity);
    }

    @PutMapping("/{id}")
    public void updateActivity(@PathVariable("id") Integer id, @RequestBody Activity activity) {
        if (!id.equals(activity.getId())) {
            throw new IllegalArgumentException("The id is not matched.");
        }
        activityService.updateActivity(activity);
    }
}

好了，以上就是实现的全部内容。如果需要更详细的代码实现可以参考：https://github.com/shadowice0904/spring-boot-mybatis-example