springboot使用druid连接池，并配置数据源监控

首先肯定是引入druid的依赖:

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.10</version>
</dependency>

然后将druid配置到项目中：

在application.yml中加入

spring:
    datasource:
        type: com.alibaba.druid.pool.DruidDataSource
        
        ###数据源的其他配置
        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

这里配置好之后，数据源是从默认的tomcat.pool切换到了druid，可是druid的属性比如initialSize、minIdle还未生效，因为在DataSourceProperties.class下没有对应的匹配项，所以还需要我们手动配置:

新建DruidConfig.java

@Configuration
public class DruidConfig {
    // 将所有前缀为spring.datasource下的配置项都加载到DataSource中
    @ConfigurationProperties(prefix = "spring.datasource")
    @Bean
    public DataSource druidDataSource() {
        return new DruidDataSource();
    }
}

至此，Druid的所有配置都已完成，打断点可以看到配置已经生效：

最后，需要配置druid的监控页面

在上面的DruidConfig中加入代码：

@Bean
    public ServletRegistrationBean druidStatViewServlet() {
        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(),"/druid/*");
        Map<String, String> initParams = new HashMap<>();
        //　可配的属性都在 StatViewServlet 和其父类下
        initParams.put("loginUsername", "admin-druid");
        initParams.put("loginPassword", "111111");
        servletRegistrationBean.setInitParameters(initParams);
        return servletRegistrationBean;
    }

    @Bean
    public FilterRegistrationBean druidWebStatFilter() {
        FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean(new WebStatFilter());
        Map<String, String> initParams = new HashMap<>();
        initParams.put("exclusions", "*.js,*.css,/druid/*");
        filterRegistrationBean.setInitParameters(initParams);
        filterRegistrationBean.setUrlPatterns(Arrays.asList("/*"));
        return filterRegistrationBean;
    }

打开浏览器测试输入：http://localhost:8080/druid/login.html

可以看到

输入我们刚才在servlet中配置的账号密码就可以登录了