SpringBoot2.2 配置druid连接池

SpringBoot2.2默认使用的连接池是HikariCP
Druid连接池是阿里巴巴开源的数据库连接池项目。Druid连接池为监控而生，内置强大的监控功能，监控特性不影响性能。功能强大，能防SQL注入，内置Loging能诊断Hack应用行为。

这里不进行两者的对比分析，单纯讲如何配置druid连接池

1.添加依赖

添加druid还有另一种，其它与下面相同，换成druid，好像说不用starter的在配置文件中不会有自动提示

        
            com.alibaba
            druid-spring-boot-starter
            1.1.10
        


        
            mysql
            mysql-connector-java
        

2.配置application.yml(我使用的yml，所以以此为例来讲)

spring:
  datasource:
    druid:
      driverClassName: com.mysql.jdbc.Driver
      url: jdbc:mysql://localhost:3306/xxx?serverTimezone=GMT%2B8&characterEncoding=utf-8
      username: xxx
      password: xxx
      #初始化时建立物理连接的个数
      initial-size: 5
      #最大连接池数量
      max-active: 10
      #最小连接池数量
      min-idle: 5
      #获取连接时最大等待时间，单位毫秒
      max-wait: 60000
      # 超过时间限制是否回收
      removeAbandoned: true
      # 当连接超过3分钟后会强制进行回收
      removeAbandonedTimeout: 180
      #      打开PSCache，并且指定每个连接上PSCache的大小
      pool-prepared-statements: true
      max-pool-prepared-statement-per-connection-size: 20
      #      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
      min-evictable-idle-time-millis: 300000
      max-evictable-idle-time-millis: 60000
      #用来检测连接是否有效的sql 必须是一个查询语句。mysql中为 select 'x'， oracle中为 select 1 from dual
      validation-query: select 'x'
      # validation-query-timeout: 5000
      #申请连接时会执行validationQuery检测连接是否有效,开启会降低性能,默认为true
      test-on-borrow: false
      #归还连接时会执行validationQuery检测连接是否有效,开启会降低性能,默认为true
      test-on-return: false
      test-while-idle: true
      #通过connectProperties属性来打开mergeSql功能，慢SQL记录
      connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
      #filters: #配置多个英文逗号分隔(统计，sql注入)
      filters: stat,wall
      #配置stat-view-servlet
      stat-view-servlet:
        #允许开启监控
        enabled: true
        #监控面板路径
        url-pattern: /druid/*

3.配置配置类

import org.springframework.context.annotation.Configuration;
import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.core.JdbcTemplate;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Configuration
public class DruidConfig {
    private static final Logger logger = LoggerFactory.getLogger(DruidConfig.class);

    @Value("${spring.datasource.druid.url}")
    private String dbUrl;
    @Value("${spring.datasource.druid.username}")
    private String username;
    @Value("${spring.datasource.druid.password}")
    private String password;
    @Value("${spring.datasource.druid.driverClassName}")
    private String driverClassName;
    @Value("${spring.datasource.druid.initial-size}")
    private int initialSize;
    @Value("${spring.datasource.druid.max-active}")
    private int maxActive;
    @Value("${spring.datasource.druid.min-idle}")
    private int minIdle;
    @Value("${spring.datasource.druid.max-wait}")
    private int maxWait;
    @Value("${spring.datasource.druid.pool-prepared-statements}")
    private boolean poolPreparedStatements;
    @Value("${spring.datasource.druid.max-pool-prepared-statement-per-connection-size}")
    private int maxPoolPreparedStatementPerConnectionSize;
    @Value("${spring.datasource.druid.time-between-eviction-runs-millis}")
    private int timeBetweenEvictionRunsMillis;
    @Value("${spring.datasource.druid.min-evictable-idle-time-millis}")
    private int minEvictableIdleTimeMillis;
    @Value("${spring.datasource.druid.max-evictable-idle-time-millis}")
    private int maxEvictableIdleTimeMillis;
    @Value("${spring.datasource.druid.validation-query}")
    private String validationQuery;
    @Value("${spring.datasource.druid.test-while-idle}")
    private boolean testWhileIdle;
    @Value("${spring.datasource.druid.test-on-borrow}")
    private boolean testOnBorrow;
    @Value("${spring.datasource.druid.test-on-return}")
    private boolean testOnReturn;
    @Value("${spring.datasource.druid.filters}")
    private String filters;
    @Value("{spring.datasource.druid.connection-properties}")

    private String connectionProperties;

    /**
     * Druid连接池配置
     * @return
     */
    //声明其为Bean实例
    @Bean
    public DruidDataSource dataSource() {
        DruidDataSource datasource = new DruidDataSource();
        datasource.setUrl(dbUrl);
        datasource.setUsername(username);
        datasource.setPassword(password);
        datasource.setDriverClassName(driverClassName);
        datasource.setInitialSize(initialSize);
        datasource.setMinIdle(minIdle);
        datasource.setMaxActive(maxActive);
        datasource.setMaxWait(maxWait);
        datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);
        datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
        datasource.setMaxEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
        datasource.setValidationQuery(validationQuery);
        datasource.setTestWhileIdle(testWhileIdle);
        datasource.setTestOnBorrow(testOnBorrow);
        datasource.setTestOnReturn(testOnReturn);
        datasource.setPoolPreparedStatements(poolPreparedStatements);
        datasource.setMaxPoolPreparedStatementPerConnectionSize(maxPoolPreparedStatementPerConnectionSize);
        try {
            datasource.setFilters(filters);
        } catch (Exception e) {
            logger.error("druid configuration initialization filter", e);
        }
        datasource.setConnectionProperties(connectionProperties);
        return datasource;
    }

    /**
     * JDBC操作配置
     * @param dataSource
     * @return
     */
    @Bean(name = "dataOneTemplate")
    public JdbcTemplate jdbcTemplate (@Autowired DruidDataSource dataSource){
        return new JdbcTemplate(dataSource) ;
    }

    /**
     * 配置 Druid 监控界面
     */
    @Bean
    public ServletRegistrationBean statViewServlet(){
        ServletRegistrationBean srb =
                new ServletRegistrationBean(new StatViewServlet(),"/druid/*");
        //设置控制台管理用户
        srb.addInitParameter("loginUsername","root");
        srb.addInitParameter("loginPassword","root");
        //是否可以重置数据。禁用HTML页面上的“Reset All”功能
        srb.addInitParameter("resetEnable","false");
        return srb;
    }

    @Bean
    public FilterRegistrationBean statFilter(){
        //创建过滤器
        FilterRegistrationBean frb =
                new FilterRegistrationBean(new WebStatFilter());
        //设置过滤器过滤路径
        frb.addUrlPatterns("/*");
        //忽略过滤的形式
        frb.addInitParameter("exclusions",
                "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
        return frb;
    }

}

看到最后配置了自定义@Bean，statFilter， 还需要排除原来的statFilter的自动注入

在SpringBoot启动类中的@SpringBootApplication注解中添加：

@SpringBootApplication(exclude={DataSourceAutoConfiguration.class, DruidDataSourceAutoConfigure.class})

4.为什么application.yml中要配置

# 超过时间限制是否回收
removeAbandoned: true
# 当连接超过3分钟后会强制进行回收
removeAbandonedTimeout: 180

如果不进行此配置，在运行中有可能出现druid连接池超时回收的问题，导致没有空闲连接可用而报错

Could not get JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 60009, active 10, max-active 10, creating 0

还可以再加一个配置

logAbandoned: true 关闭abandoned连接异常时输出到日志，不过这个影响性能

 

欢迎大家指正，交流学习