idea 2019.1
maven
Spring Boot 2.1.5
jdk 1.8
Win 10
...
使用 idea 自动化创建Spring Boot项目,这里不再赘述了, 不过需要注意的是, 我们需要把Mysql驱动勾选上:
 
 
 需要其他依赖, 可以自己勾选;
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.5.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.carson</groupId>
    <artifactId>spring-boot-06-data-jdbc</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>spring-boot-06-data-jdbc</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</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>
        
         <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.16</version>
        </dependency>
      
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>
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 然后我的配置文件选择 yml 后缀的:
spring:
  datasource: 
    password: root
    username: root
    url: jdbc:mysql://localhost:3306/ssm?serverTimezone=UTC
    driver-class-name: com.mysql.cj.jdbc.Driver
    # 指定连接池类型
    type: com.alibaba.druid.pool.DruidDataSource
# ------------分割线---------------------------
# 这下面的东西先不要添加到你的配置文件里,因为不会生效
    initialSize: 5
    minIdle: 5
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: SELECT 1 FROM DUAL
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
    #   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
    filters: stat,wall,log4j
    maxPoolPreparedStatementPerConnectionSize: 20
    useGlobalDataSourceStat: true
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=500
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 不过让我们先测试一下我们的连接池 是否为 Druid 连接池,
打开我们test包下的测试类, 我这里放上我的完整代码:
package com.carson.springboot;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import javax.lang.model.element.VariableElement;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringBoot06DataJdbcApplicationTests {
    @Autowired
    DataSource dataSource;
    @Test
    public void contextLoads() throws SQLException {
        System.out.println(dataSource.getClass());
        Connection connection = dataSource.getConnection();
        System.out.println(connection);
        connection.close();
    }
}
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 运行此测试你将会看到控制台输出的连接池类型:
 
 
 正是我们需要的连接池类型
还记得刚才说的不生效的那些配置吗? 现在让我们来设置一下;
首先创建一个config配置类:
package com.carson.springboot.config;
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.sql.DataSource;
@Configuration
public class DruidConfig {
    @ConfigurationProperties(prefix = "spring.datasource")
    @Bean 
    public DataSource druid() {
        return new DruidDataSource();
    }
}
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 @ConfigurationProperties: 前缀, 表示带这些前缀的配置生效
然后在测试类打个断点,debug运行一下:
 
 
 结果:
 
 
 可以看到属性是正确的
依然是刚才的 DruidConfig 配置类,我们来添加以下方法:
@Bean
    public ServletRegistrationBean statViewServlet() {
        ServletRegistrationBean bean = new ServletRegistrationBean          					(new StatViewServlet(), "/druid/*");
        
        Map<String, String> initParams = new HashMap<>();
        //   账号,
        initParams.put("loginUsername", "admin");
        // 密码,
        initParams.put("loginPassword", "123456");
        // 允许登录的ip(为空 就是所有都允许)
        initParams.put("allow", "");
        // 然后是不允许的ip地址
        initParams.put("deny", "192.123.11.11");
       	// 设置初始化参数
        bean.setInitParameters(initParams);
        return bean;
    }
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 这些参数是从哪里来的呢? 就是下面:
 
 
 // 2)配置一个监控的 filter
    @Bean
    public FilterRegistrationBean webStatFilter() {
        FilterRegistrationBean bean = new FilterRegistrationBean();
        bean.setFilter(new WebStatFilter());
        
        Map<String, String> initParams = new HashMap<>();
        // 不拦截那些属性
        initParams.put("exclusions","*.js,*.css,/druid/*");
		// 设置初始化参数
        bean.setInitParameters(initParams);
		// 默认拦截所有
        bean.setUrlPatterns(Arrays.asList("/*"));
        return bean;
    }
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 设置好这个,我们可以启动Spring Boot的主类, 然后访问 德鲁伊(Druid)监视器: http://localhost:8080/druid
这个路径是druid默认的路径, 你会看到一个登录页面:
 
 
 密码就是我们刚才设置的 admin 和 123456
查看效果:
 
 
 为了查看以下我们的 SQL监控 的效果, 我们来写一个 controller :
package com.carson.springboot.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import java.util.List;
import java.util.Map;
@Controller
public class HelloController {
    @Autowired
    JdbcTemplate jdbcTemplate;
    @ResponseBody
    @GetMapping
    public Map<String, Object> map() {
        List<Map<String, Object>> list = jdbcTemplate.queryForList("select * from user ");
        return list.get(0);
    }
}
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 并且向网页发送 query 请求:
 
 
 然后查看 SQL 监控:
 
 
 END~~