导入依赖
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.2.5</version>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
</dependency>


yaml配置文件

spring:
  datasource:
    username: root
    password: 123456
    url: jdbc:mysql://localhost:3306/school?useUnicode=true&characterEncoding=utf-8
    driver-class-name: com.mysql.cj.jdbc.Driver
    type: com.alibaba.druid.pool.DruidDataSource

    # 配置监控统计拦截的filters, 去掉后监控界面sql无法统计, 'wall'用于防火墙防御sql注入，stat监控统计,logback日志
    filters: stat,wall
    # Spring监控AOP切入点，如x.y.z.service.*,配置多个英文逗号分隔
    #aop-patterns: com.springboot.servie.*
    # lowSqlMillis用来配置SQL慢的标准，执行时间超过slowSqlMillis的就是慢
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500


controller层

@RestController
public class JDBCController {

    @Autowired
    JdbcTemplate jdbcTemplate;

    //查数据库的所有信息
    //没有实体类，数据库中的字段如何获取  万能的Map
    @GetMapping("/stuList")
    public List<Map<String,Object>> stuList(){
        String sql = "select * from stu";
        List<Map<String, Object>> maps = jdbcTemplate.queryForList(sql);
        return maps;
    }

    @GetMapping("/stuList/add")
    public String addStu(){
        String sql = "insert into stu(id,name,gender,age,birthday,score) values(4,'马王八','男',18,'2021-11-11',80)";
        jdbcTemplate.update(sql);
        return "update-ok";
    }

    @GetMapping("/stuList/{id}")
    public String deletStu(@PathVariable("id") int id){
        String sql = "update stu set id=?,name=?,gender=?,age=?,birthday=?,score=? where id="+id;
        jdbcTemplate.update(sql);
        return "update-ok";
    }
    @GetMapping("/deleteList/{id}")
    public String deleteStu(@PathVariable("id") int id){
        String sql = "delete  from  stu where id=?";
        jdbcTemplate.update(sql,id);
        return "delete-ok";
    }




config层

@Configuration
public class DruidConfig {

    @ConfigurationProperties(prefix = "spring.datasource")
    @Bean
    public DataSource druidDataSource(){
        return  new DruidDataSource();
    }

    @Bean
    public ServletRegistrationBean StatViewServlet(){
        ServletRegistrationBean<StatViewServlet> bean = new ServletRegistrationBean<>(new StatViewServlet(), "/druid/*");

        HashMap<String, String> initParameters = new HashMap<>();
        initParameters.put("loginUsername","admin");
        initParameters.put("loginPassword","123456");

        initParameters.put("allow","");

        bean.setInitParameters(initParameters);
        return bean;
    }
    @Bean
    public FilterRegistrationBean webStaFilter(){
        FilterRegistrationBean bean = new FilterRegistrationBean();

        bean.setFilter(new WebStatFilter());


        HashMap<String, String> initParameters = new HashMap<>();
        initParameters.put("exclusions","*.js,*.css");

        bean.setInitParameters(initParameters);
        return bean;
    }
}