SpringBoot整合Mybatis和Redis案例

た入场券 2022-03-02 10:38 277阅读 0赞

### 项目结构： ###

![20190320111059419.png][]

### 一、引入相关jar ###

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-cache</artifactId>
    </dependency>
    
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-redis</artifactId>
    </dependency>
    
    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>1.3.3</version>
    </dependency>

### 二、配置全局环境  ###

1）、配置application.properties：

#数据源配置
    spring.datasource.url=jdbc:mysql://localhost:3306/spring_cache??useUnicode=true&characterEncoding=UTF-8  
    spring.datasource.username=root
    spring.datasource.password=root
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver
    #开启驼峰命名规则
    mybatis.configuration.map-underscore-to-camel-case=true
    #打印mapper日志
    logging.level.com.zhq.springboot.mapper=debug
    debug=true
    #指定redis
    spring.redis.host=192.168.43.118

2）、启动类SpringbootCacheApplication中配置扫描Mybatis映射文件以及开启缓存：

@MapperScan("com.zhq.springboot.mapper")//扫描mybatis映射文件
    @SpringBootApplication
    @EnableCaching//开启缓存
    public class SpringbootCacheApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(SpringbootCacheApplication.class, args);
        }
    
    }

### 三、自定义Redis配置以Json格式保存对象数据 ###

@Configuration
    public class MyRedisConfig {
    
        @Bean
        public RedisTemplate<Object, Employee> empRedisTemplate(
                RedisConnectionFactory redisConnectionFactory)
                throws UnknownHostException {
            RedisTemplate<Object, Employee> template = new RedisTemplate<Object, Employee>();
            template.setConnectionFactory(redisConnectionFactory);
            Jackson2JsonRedisSerializer<Employee> ser = new Jackson2JsonRedisSerializer<Employee>(Employee.class);
            template.setDefaultSerializer(ser);
            return template;
        }
        @Bean
        public RedisTemplate<Object, Department> deptRedisTemplate(
                RedisConnectionFactory redisConnectionFactory)
                throws UnknownHostException {
            RedisTemplate<Object, Department> template = new RedisTemplate<Object, Department>();
            template.setConnectionFactory(redisConnectionFactory);
            Jackson2JsonRedisSerializer<Department> ser = new Jackson2JsonRedisSerializer<Department>(Department.class);
            template.setDefaultSerializer(ser);
            return template;
        }
    
    
    
        //CacheManagerCustomizers可以来定制缓存的一些规则
        @Primary  //将某个缓存管理器作为默认的
        @Bean
        public RedisCacheManager employeeCacheManager(RedisTemplate<Object, Employee> empRedisTemplate){
            RedisCacheManager cacheManager = new RedisCacheManager(empRedisTemplate);
            //key多了一个前缀
    
            //使用前缀，默认会将CacheName作为key的前缀
            cacheManager.setUsePrefix(true);
    
            return cacheManager;
        }
    
        @Bean
        public RedisCacheManager deptCacheManager(RedisTemplate<Object, Department> deptRedisTemplate){
            RedisCacheManager cacheManager = new RedisCacheManager(deptRedisTemplate);
            //key多了一个前缀
    
            //使用前缀，默认会将CacheName作为key的前缀
            cacheManager.setUsePrefix(true);
    
            return cacheManager;

### 四、编写整合Demo ###

1）、编写实体

public class Employee implements Serializable {
    	
    	private Integer id;
    	private String lastName;
    	private String email;
    	private Integer gender; //性别 1男  0女
    	private Integer dId;
    ...

public class Department {
    	
    	private Integer id;
    	private String departmentName;
    	...

2）、编写映射接口

public interface EmployeeMapper {
        @Select("select * from employee where id=#{id}")
        public Employee getEmpById(Integer id);
    
        @Update("update employee set lastName=#{lastName},email=#{email},gender=#{gender},d_id=#{dId} where id=#{id}")
        public void updateEmp(Employee employee);
    
        @Delete("delete employee where id=#{id}")
        public void deleteEmpById(Integer id);
    
        @Insert("insert into employee(lastName,email,gender,d_id) values(#{lastName},#{email},#{gender},#{dId})")
        public void insertEmp(Employee employee);
    
        @Select("select * from employee where lastName=#{lastName}")
        public Employee getEmpByLastName(String lastName);

public interface DepartmentMapper {
    
        @Select("SELECT * FROM department WHERE id = #{id}")
        Department getDeptById(Integer id);
    }

3）、编写Service

@Service
    @CacheConfig(cacheManager = "employeeCacheManager")
    public class EmployeeService {
        @Autowired
        EmployeeMapper employeeMapper;
    
        /**
         * 将方法的运行结果进行缓存：以后再要相同的数据，直接从缓存中获取，不用调用方法
         * CacheManager管理多个Cache组件的，对缓存的真正CRUD操作在Cache组件中，每一个缓存组件有自己唯一一个名字；
         * 几个属性：
         *      cacheNames/value:指定缓存组件的名字；
         *      key缓存数据时使用的key，可以用它来指定，默认是使用方法参数的值 eg:1-方法的返回值
         *        可编写SpEL表达式,eg:
         *        #id表示参数id的值 相当于#a0 #p0 #root.args[0]
         *      keyGenerator:key的生成器；可以自己指定key的生成器的组件id
         *      keyGenerator/key:二选一，用其中一个就行
         *      cacheManager:指定缓存管理器，或者指定缓存解析器cacheResolver
         *      condition:指定符合条件的情况下才缓存
         *      unless:否定缓存，当unless指定的条件为true,方法的返回值就不会被缓存；可以获取到结果集进行判断
         *          eg:unless="#result==null"
         *      sync:是否使用异步模式
         *
         * @param id
         * @return
         */
        @Cacheable(cacheNames = "emp",key = "#id",condition = "#id>0",unless = "#result==null")
        public Employee getEmp(Integer id){
            System.out.println("查询"+id+"号员工");
            Employee emp = employeeMapper.getEmpById(id);
            return emp;
        }
        /**
         * @CachePut：既调用方法，又更新缓存；
         * 修改了数据库的某个数据，同时又更新缓存
         */
        @CachePut(cacheNames= "emp",key = "#e.id")
        public Employee updateEmp(Employee e){
            System.out.println("更新员工"+e);
            employeeMapper.updateEmp(e);
            return e;
        }
    
        /**
         * 清除缓存
         * @param id
         */
        @CacheEvict(value = "emp",key = "#id")
        public void deleteEmp(Integer id){
            System.out.println("删除员工："+id);
            //employeeMapper.deleteEmpById(id);
        }
    
        @Caching(
            cacheable = {
                    @Cacheable(value = "emp",key = "#lastName")
            },
            put = {
                    @CachePut(value = "emp",key = "#result.id"),
                    @CachePut(value = "emp",key = "#result.email")
            }
        )
        public Employee getEmpByLastName(String lastName){
            return employeeMapper.getEmpByLastName(lastName);
        }
    
    
    
        public Employee insertEmp(Employee employee){
            employeeMapper.insertEmp(employee);
            return employee;
        }
    }

@Service
    public class DeptService {
    
        @Autowired
        DepartmentMapper departmentMapper;
    
        @Qualifier("deptCacheManager")
        @Autowired
        RedisCacheManager deptCacheManager;
    
    
        /**
         *  缓存的数据能存入redis；
         *  第二次从缓存中查询就不能反序列化回来；
         *  存的是dept的json数据;CacheManager默认使用RedisTemplate<Object, Employee>操作Redis
         *
         *
         * @param id
         * @return
         */
    //    @Cacheable(cacheNames = "dept",cacheManager = "deptCacheManager")
    //    public Department getDeptById(Integer id){
    //        System.out.println("查询部门"+id);
    //        Department department = departmentMapper.getDeptById(id);
    //        return department;
    //    }
    
        // 使用缓存管理器得到缓存，进行api调用
        public Department getDeptById(Integer id){
            System.out.println("查询部门"+id);
            Department department = departmentMapper.getDeptById(id);
    
            //获取某个缓存
            Cache dept = deptCacheManager.getCache("dept");
            dept.put("dept:1",department);
    
            return department;
        }
    
    
    }

4）、编写Controller

@RestController
    public class EmployeeController {
        @Autowired
        EmployeeService employeeService;
    
        /**
         * 根据id查询员工
         * @param id
         * @return
         */
        @GetMapping("/emp/{id}")
        public Employee getEmp(@PathVariable("id") Integer id){
            Employee emp = employeeService.getEmp(id);
            return emp;
        }
    
        /**
         * 修改员工
         * @param employee
         * @return
         */
        @GetMapping("/emp")
        public Employee updateEmp(Employee employee){
            return  employeeService.updateEmp(employee);
        }
    
        /**
         * 添加员工
         * @param employee
         * @return
         */
        @GetMapping("/emps")
        public Employee insetEmp(Employee employee){
            Employee employee1 = employeeService.insertEmp(employee);
            return employee1;
        }
    
        /**
         * 删除员工
         * @param id
         * @return
         */
        @GetMapping("/delemp/{id}")
        public String deleteEmp(@PathVariable("id") Integer id){
            employeeService.deleteEmp(id);
            return "success";
        }
    
        /**
         * 按名字查询
         * @param lastName
         * @return
         */
        @GetMapping("/emp/lastname/{lastName}")
        public Employee getEmpByLastName(@PathVariable("lastName")String lastName){
            return employeeService.getEmpByLastName(lastName);
        }
    
    
    }

@RestController
    public class DeptController {
    
        @Autowired
        DeptService deptService;
    
        @GetMapping("/dept/{id}")
        public Department getDept(@PathVariable("id") Integer id){
            return deptService.getDeptById(id);
        }
    }

5）、测试Demo

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3htMzkzMzkyNjI1_size_16_color_FFFFFF_t_70][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3htMzkzMzkyNjI1_size_16_color_FFFFFF_t_70 1][]

[20190320111059419.png]: /images/20220302/10ff3804e5504977aabb105db9da73a8.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3htMzkzMzkyNjI1_size_16_color_FFFFFF_t_70]: /images/20220302/24d7a6f5b3b04c2d86eb55f71645b5ff.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3htMzkzMzkyNjI1_size_16_color_FFFFFF_t_70 1]: /images/20220302/55662282be414458b1bcb0d2ee974c76.png