SpringBoot学习：整合MyBatis，使用Druid连接池

一时失言乱红尘 2022-06-18 13:09 228阅读 0赞

项目下载地址：http://download.csdn.NET/detail/aqsunkai/9805821

（一）添加pom依赖：

<dependency>
          <groupId>org.mybatis.spring.boot</groupId>
          <artifactId>mybatis-spring-boot-starter</artifactId>
          <version>1.2.0</version>
        </dependency>
        
        <dependency>
          <groupId>mysql</groupId>
          <artifactId>mysql-connector-java</artifactId>
          <version>6.0.6</version>
        </dependency>
        
        <dependency>
          <groupId>com.alibaba</groupId>
          <artifactId>druid</artifactId>
          <version>1.0.29</version>
        </dependency>

（二）项目结构如下：

![Center][]

mapper接口在java目录下，相应的写sql语句的xml在resource目录下，在Application启动类中加入注解：

@ServletComponentScan
    @MapperScan("com.sun.**.mapper") //配置扫描mapper接口的地址

@ServletComponentScan 设置启动时spring能够扫描到我们自己编写的servlet和filter, 用于Druid监控

@MapperScan 用于扫描的mapper接口

在配置文件中加入：

# mybatis_config
    mybatis:
        mapper-locations: classpath:mapper/**/*.xml
    #datasource
    spring:
        datasource:
            name: era
            url: jdbc:mysql://localhost:3306/spring_boot?useUnicode=true&characterEncoding=UTF-8&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC
            username: root
            password: 123456
            # 使用druid数据源
            type: com.alibaba.druid.pool.DruidDataSource
            driver-class-name: com.mysql.cj.jdbc.Driver
            # 下面为连接池的补充设置，应用到上面所有数据源中
            # 初始化大小，最小，最大
            initialSize: 5
            minIdle: 5
            maxActive: 20
            # 配置获取连接等待超时的时间
            maxWait: 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
            timeBetweenEvictionRunsMillis: 60000
            # 配置一个连接在池中最小生存的时间，单位是毫秒
            minEvictableIdleTimeMillis: 300000
            validationQuery: SELECT 1 FROM DUAL
            testWhileIdle: true
            testOnBorrow: false
            testOnReturn: false
            # 打开PSCache，并且指定每个连接上PSCache的大小
            poolPreparedStatements: true
            maxPoolPreparedStatementPerConnectionSize: 20
            # 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
            spring.datasource.filters: stat,wall,log4j
            # 通过connectProperties属性来打开mergeSql功能；慢SQL记录
            connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
            # 合并多个DruidDataSource的监控数据
            #useGlobalDataSourceStat: true

用于扫描mybatis的映射文件xml，和加载连接池

日志文件中加入：

<logger name="com.sun" level="debug" />

用于在控制台打印sql语句

DataSource的配置启动管理类如下：

package com.sun.configuration;
    
    import com.alibaba.druid.pool.DruidDataSource;
    import com.alibaba.druid.support.http.StatViewServlet;
    import com.alibaba.druid.support.http.WebStatFilter;
    import com.alibaba.druid.support.spring.stat.DruidStatInterceptor;
    import org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator;
    import org.springframework.boot.bind.RelaxedPropertyResolver;
    import org.springframework.boot.web.servlet.FilterRegistrationBean;
    import org.springframework.boot.web.servlet.ServletRegistrationBean;
    import org.springframework.context.EnvironmentAware;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.core.env.Environment;
    import org.springframework.transaction.annotation.EnableTransactionManagement;
    
    import javax.sql.DataSource;
    import java.sql.SQLException;
    import java.util.HashMap;
    import java.util.Map;
    
    @Configuration
    @EnableTransactionManagement
    /**
     * Druid的DataResource配置类
     * 凡是被Spring管理的类，实现接口 EnvironmentAware 重写方法 setEnvironment 可以在工程启动时，
     * 获取到系统环境变量和application配置文件中的变量。 还有一种方式是采用注解的方式获取 @value("${变量的key值}")
     * 获取application配置文件中的变量。 这里采用第一种要方便些
     * Created by sun on 2017-1-20.
     */
    public class DruidDataSourceConfig implements EnvironmentAware {
    
    	private RelaxedPropertyResolver propertyResolver;
    
    	public void setEnvironment(Environment env) {
    		this.propertyResolver = new RelaxedPropertyResolver(env, "spring.datasource.");
    	}
    
    	@Bean
    	public DataSource dataSource() {
    		DruidDataSource datasource = new DruidDataSource();
    		datasource.setUrl(propertyResolver.getProperty("url"));
    		datasource.setDriverClassName(propertyResolver.getProperty("driver-class-name"));
    		datasource.setUsername(propertyResolver.getProperty("username"));
    		datasource.setPassword(propertyResolver.getProperty("password"));
    		datasource.setInitialSize(Integer.valueOf(propertyResolver.getProperty("initialSize")));
    		datasource.setMinIdle(Integer.valueOf(propertyResolver.getProperty("minIdle")));
    		datasource.setMaxWait(Long.valueOf(propertyResolver.getProperty("maxWait")));
    		datasource.setMaxActive(Integer.valueOf(propertyResolver.getProperty("maxActive")));
    		datasource.setMinEvictableIdleTimeMillis(
    				Long.valueOf(propertyResolver.getProperty("minEvictableIdleTimeMillis")));
    		try {
    			datasource.setFilters("stat,wall");
    		} catch (SQLException e) {
    			e.printStackTrace();
    		}
    		return datasource;
    	}
    
    	@Bean
    	public ServletRegistrationBean druidServlet() {
    		ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean();
    		servletRegistrationBean.setServlet(new StatViewServlet());
    		servletRegistrationBean.addUrlMappings("/druid/*");
    		Map<String, String> initParameters = new HashMap<String, String>();
    		// initParameters.put("loginUsername", "druid");// 用户名
    		// initParameters.put("loginPassword", "druid");// 密码
    		initParameters.put("resetEnable", "false");// 禁用HTML页面上的“Reset All”功能
    		initParameters.put("allow", "127.0.0.1"); // IP白名单 (没有配置或者为空，则允许所有访问)
    		// initParameters.put("deny", "192.168.20.38");// IP黑名单
    		// (存在共同时，deny优先于allow)
    		servletRegistrationBean.setInitParameters(initParameters);
    		return servletRegistrationBean;
    	}
    
    	@Bean
    	public FilterRegistrationBean filterRegistrationBean() {
    		FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
    		filterRegistrationBean.setFilter(new WebStatFilter());
    		filterRegistrationBean.addUrlPatterns("/*");
    		filterRegistrationBean.addInitParameter("exclusions", "*.js,*.gif,*.jpg,*.bmp,*.png,*.css,*.ico,/druid/*");
    		return filterRegistrationBean;
    	}
    
    	// 按照BeanId来拦截配置 用来bean的监控
    	@Bean(value = "druid-stat-interceptor")
    	public DruidStatInterceptor DruidStatInterceptor() {
    		DruidStatInterceptor druidStatInterceptor = new DruidStatInterceptor();
    		return druidStatInterceptor;
    	}
    
    	@Bean
    	public BeanNameAutoProxyCreator beanNameAutoProxyCreator() {
    		BeanNameAutoProxyCreator beanNameAutoProxyCreator = new BeanNameAutoProxyCreator();
    		beanNameAutoProxyCreator.setProxyTargetClass(true);
    		// 设置要监控的bean的id
    		//beanNameAutoProxyCreator.setBeanNames("sysRoleMapper","loginController");
    		beanNameAutoProxyCreator.setInterceptorNames("druid-stat-interceptor");
    		return beanNameAutoProxyCreator;
    	}
    
    }

后台执行在控制台上输出：

2017-04-07 21:25:15.904  INFO 10500 --- [io-8080-exec-10] c.s.p.controller.UserController          : 哈哈哈
    2017-04-07 21:25:15.908 DEBUG 10500 --- [io-8080-exec-10] c.s.p.m.UserMapper.selectByPrimaryKey    : ==>  Preparing: select id, nickname, email, pswd, create_time, last_login_time, status from sys_user where id = ? 
    2017-04-07 21:25:15.911 DEBUG 10500 --- [io-8080-exec-10] c.s.p.m.UserMapper.selectByPrimaryKey    : ==> Parameters: 1(Integer)
    2017-04-07 21:25:15.918 DEBUG 10500 --- [io-8080-exec-10] c.s.p.m.UserMapper.selectByPrimaryKey    : <==      Total: 1
    2017-04-07 21:25:15.920  INFO 10500 --- [io-8080-exec-10] c.s.p.controller.UserController          : admin

在页面上输入http://localhost:8080/boot/druid/可以看到监控到的sql语句执行情况：  
![Center 1][]

[Center]: /images/20220618/e18f23a805e343f0a63cecd062355896.png
[Center 1]: /images/20220618/b275d470c8d34cfd885ed8ae8e8e357b.png