通过db创建分布式锁

数据库表

create table if not exists yw_lock
(
    lock_field varchar(50) not null,
    lock_table varchar(50) not null,
    constraint pk_yw_lock
        primary key (lock_field, lock_table)
);

comment on table yw_lock is '分布式锁';

comment on column yw_lock.lock_field is '业务锁';

create index if not exists index_yw_lock_all
    on yw_lock (lock_field, lock_table);

lock实体类

@Data
@EqualsAndHashCode
@AllArgsConstructor
@NoArgsConstructor
@Table(name = "yw_lock")
public class YwLock implements Serializable {

    /**
     * 业务锁
     */
    private String lockField;

    /**
     * 业务表
     */
    private String lockTable;

}

public interface YwLockMapper {
    int lock(YwLock ywLock);
    int unLock(YwLock ywLock);
}

<insert id="lock" parameterType="YwLock">
     INSERT INTO yw_lock (
        lock_field,
        lock_table
      ) VALUES (
        #{lockField},
        #{lockTable}
     );
</insert>

<delete id="unLock" parameterType="YwLock">
    DELETE
    FROM yw_lock
    WHERE lock_field = #{lockField} and lock_table = #{lockTable}
</delete>

Service层实现

public interface IYwLockService {
    /**
     * 加锁
     */
    boolean lock(YwLock ywLock);

    /**
     * 解锁
     */
    boolean unLock(YwLock ywLock);
}

implements实现

@Service
public class YwLockServiceImpl implements IYwLockService {

    @Resource
    private YwLockMapper lockMapper;

    @Override
    @Transactional(propagation = Propagation.REQUIRES_NEW)
    public boolean lock(YwLock ywLock) {
        return lockMapper.lock(ywLock) > 0;
    }

    @Override
    @Transactional(propagation = Propagation.REQUIRES_NEW)
    public boolean unLock(YwLock ywLock) {
        return lockMapper.unLock(ywLock) > 0;
    }
}

通过service获取到lock返回为true：表示拿到锁，可以做业务操作，反知道不能做业务操作