@SpringBootApplication
public class SpringbootApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringbootApplication.class,args);
    }
}

@RestController
public class TestController {
    @RequestMapping("/hello")
    public String showHello(){
        return "hello world";
    }
}

@RestController
public class Test2Controller {
    @Value("${name}")
    private String name;

    @Value("${city[0]}")
    private String city0;

    @Value("${students[0].name}")
    private String studentname;

    @Value("${person.name}")
    private String personName;


    @Value("${maps.name}")//value注解只能获简单的值对象
    private String name1;

    @Autowired
    private Student student;

    @RequestMapping("/show")
    public String showHello() {
        System.out.println(name);
        System.out.println(city0);
        System.out.println(studentname);
        System.out.println(personName);
        
        System.out.println(">>>>"+student.getAge());

        return "hello world";
    }
}

@Component
@ConfigurationProperties(prefix = "person")
public class Student {
    private String name;
    private Integer age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

}

package com.jwang.service;

/***
 * 描述
 * @author ljh
 * @packagename com.jwang.service
 * @version 1.0
 * @date 2020/2/26
 */
@Service
public class UserService {

    public String getUser() {
        System.out.println("获取用户的信息");
        return "zhangsan";
    }
}

@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringBootApplicationTests {

    @Autowired
    private UserService userService;

   
    @Test
    public void getUser() {
        String userinfo = userService.getUser();
        System.out.println(userinfo);
    }
}

public class User implements Serializable{
    private Integer id;
    private String username;//用户名
    private String password;//密码
    private String name;//姓名
    //getter setter...
    //toString
}

package com.jwang.dao;

import com.jwang.pojo.User;

import java.util.List;

/***
 * mapper接口
 * @author ljh
 * @packagename com.jwang.dao
 * @version 1.0
 * @date 2020/2/23
 */
public interface UserMapper {
    public List<User> findAllUser();
}

@SpringBootApplication
@MapperScan(basePackages = "com.jwang.dao")
//MapperScan 用于扫描指定包下的所有的接口，将接口产生代理对象交给spriing容器
public class MybatisApplication {
    public static void main(String[] args) {
        SpringApplication.run(MybatisApplication.class,args);
    }
}

package com.jwang.service.impl;

import com.jwang.dao.UserMapper;
import com.jwang.pojo.User;
import com.jwang.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/***
 * 描述
 * @author ljh
 * @packagename com.jwang.service.impl
 * @version 1.0
 * @date 2020/2/23
 */
@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapper userMapper;

    @Override
    public List<User> findAllUser() {
        return userMapper.findAllUser();
    }
}

package com.jwang.service;

import com.jwang.pojo.User;

import java.util.List;

/***
 * 描述
 * @author ljh
 * @packagename com.jwang.service
 * @version 1.0
 * @date 2020/2/23
 */
public interface UserService {
    public List<User> findAllUser();
}

package com.jwang.controller;

import com.jwang.pojo.User;
import com.jwang.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

/***
 * 描述
 * @author ljh
 * @packagename com.jwang.controller
 * @version 1.0
 * @date 2020/2/23
 */
@RestController
@RequestMapping("/user")
public class UserController {

    @Autowired
    private UserService userService;

    @RequestMapping("/findAll")
    public List<User> findAll(){
        return userService.findAllUser();
    }
}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserMapper userMapper;

    @Autowired
    private RedisTemplate redisTemplate;

    @Override
    public List<User> findAllUser() {

        //1.获取redis中的数据
        List<User> list = (List<User>) redisTemplate.boundValueOps("key_all").get();
        //2.判断 是否有，如果有则返回，如果没有则从mysql中获取设置到redis中再返回
        if (list != null && list.size() > 0) {
            return list;
        }
        List<User> allUser = userMapper.findAllUser();

        //3 从mysql中获取设置到redis中再返回
        redisTemplate.boundValueOps("key_all").set(allUser);

        return allUser;
    }
}

@SpringBootApplication
@MapperScan(basePackages = "com.jwang.dao")
//MapperScan 用于扫描指定包下的所有的接口，将接口产生代理对象交给spriing容器
public class MybatisApplication {
    public static void main(String[] args) {
        SpringApplication.run(MybatisApplication.class,args);
    }

    @Bean
    public RedisTemplate<Object, Object> redisTemplate(
        RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        RedisTemplate<Object, Object> template = new RedisTemplate<>();
        template.setConnectionFactory(redisConnectionFactory);
        //设置key的值为字符串序列化方式 那么在使用过程中key 一定只能是字符串
        template.setKeySerializer(new StringRedisSerializer());
        //设置value的序列化机制为JDK自带的方式
        template.setValueSerializer(new JdkSerializationRedisSerializer());
        return template;
    }

}