springboot2 + mysql + druid

第一步导入坐标

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.6.1</version>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
        <version>2.6.7</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jdbc</artifactId>
        <version>2.6.7</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.28</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/com.alibaba/druid-spring-boot-starter -->
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
        <version>1.2.8</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.30</version>
        <scope>provided</scope>
    </dependency>


</dependencies>

第二步: 创建yml文件

server:
  port: 8001
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    username: root
    password: root
    url: jdbc:mysql://localhost:3306/springboot-learn?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai&useSSL=false
    type: com.alibaba.druid.pool.DruidDataSource
    druid:
      #初始化连接池大小
      initial-size: 5
      #配置最小连接数
      min-idle: 5
      #配置最大连接数
      max-active: 200
      #配置连接等待超时时间
      max-wait: 60000
      #配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒
      time-between-eviction-runs-millis: 60000
      #配置一个连接在池中最小生存的时间，单位是毫秒
      min-evictable-idle-time-millis: 300000
      #测试连接
      validation-query: SELECT 1 FROM DUAL
      #申请连接的时候检测，建议配置为true，不影响性能，并且保证安全
      test-while-idle: true
      #获取连接时执行检测，建议关闭，影响性能
      test-on-borrow: false
      #归还连接时执行检测，建议关闭，影响性能
      test-on-return: false
      #是否开启PSCache，PSCache对支持游标的数据库性能提升巨大，oracle建议开启，mysql下建议关闭
      pool-prepared-statements: false
      #开启poolPreparedStatements后生效
      max-pool-prepared-statement-per-connection-size: 20
      #配置扩展插件，常用的插件有=>stat:监控统计  log4j:日志  wall:防御sql注入
      filters: stat,wall,slf4j
      #打开mergeSql功能；慢SQL记录
      connection-properties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      #配置DruidStatFilter
      web-stat-filter:
        enabled: true
        url-pattern: "/*"
        exclusions: "*.js,*.gif,*.jpg,*.bmp,*.png,*.css,*.ico,/druid/*"
      #配置DruidStatViewServlet
      stat-view-servlet:
        url-pattern: "/druid/*"
        #登录名
        login-username: root
        #登录密码
        login-password: root

第三步: 设置启动类

@SpringBootApplication
public class MysqlApplication {
    public static void main(String[] args) {
        SpringApplication.run(MysqlApplication.class);
    }
}

第四部: 验证mysql连接是否正常

@RestController
@RequestMapping("/user")
public class UserController {
    @Resource
    private DataSource dataSource;

    @Resource
    private JdbcTemplate jdbcTemplate;

    @GetMapping("/get/{id}")
    public User getUserById(@PathVariable("id") String id) throws Exception {
        System.out.println(id);
        Connection connection = dataSource.getConnection();
        DruidDataSource druidDataSource = (DruidDataSource) dataSource;
       
        //打印连接池最大数量
         
        System.out.println(druidDataSource.getMaxActive());
        String sql = "select * from user where id= ?";
        User user = jdbcTemplate.queryForObject(sql, new BeanPropertyRowMapper<>(User.class), id);
        System.out.println(user);
        druidDataSource.close();
        connection.close();
        return user;
    }

    @GetMapping("/test")
    private String test() {
        return "test";
    }
}

完工