Druid - SpringBoot配置数据库连接池druid

• 关于Druid

    DRUID是阿里巴巴开源平台上一个数据库连接池实现，它结合了C3P0、DBCP、PROXOOL等DB池的优点，同时加入了日志监控，可以很好的监控DB池连接和SQL的执行情况，可以说是针对监控而生的DB连接池，是目前最好的连接池。

• yml文件配置

spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.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: 10
    minIdle: 2
    maxActive: 30
    #配置获取连接等待超时的时间
    maxWait: 6000
    #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
    filters: stat,wall
    #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
    #druid recycle
    removeAbandoned: true
    removeAbandonedTimeout: 100
    logAbandoned: false

• 配置类

        配置自己的datasource:

@Autowired
    private Environment environment;


    @Bean(name = \"myDatasource\")
    public DataSource datasource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setUrl(environment.getProperty(\"datasource.my.jdbcUrl\"));
        dataSource.setUsername(environment.getProperty(\"datasource.my.username\"));
        dataSource.setPassword(environment.getProperty(\"datasource.my.password\"));
        dataSource.setDriverClassName(environment.getProperty(\"spring.datasource.driver-class-name\"));
        dataSource.setInitialSize(environment.getProperty(\"spring.datasource.initialSize\", Integer.class));
        dataSource.setMinIdle(environment.getProperty(\"spring.datasource.minIdle\", Integer.class));
        dataSource.setMaxActive(environment.getProperty(\"spring.datasource.maxActive\", Integer.class));
        dataSource.setMaxWait(environment.getProperty(\"spring.datasource.maxWait\", Long.class));
        dataSource.setTimeBetweenEvictionRunsMillis(environment.getProperty(\"spring.datasource.timeBetweenEvictionRunsMillis\", Long.class));
        dataSource.setMinEvictableIdleTimeMillis(environment.getProperty(\"spring.datasource.minEvictableIdleTimeMillis\", Long.class));
        dataSource.setValidationQuery(environment.getProperty(\"spring.datasource.validationQuery\"));
        dataSource.setTestWhileIdle(environment.getProperty(\"spring.datasource.testWhileIdle\", Boolean.class));
        dataSource.setTestOnBorrow(environment.getProperty(\"spring.datasource.testOnBorrow\", Boolean.class));
        dataSource.setTestOnReturn(environment.getProperty(\"spring.datasource.testOnReturn\", Boolean.class));
        dataSource.setPoolPreparedStatements(environment.getProperty(\"spring.datasource.poolPreparedStatements\", Boolean.class));
        dataSource.setMaxPoolPreparedStatementPerConnectionSize(environment.getProperty(\"spring.datasource.maxPoolPreparedStatementPerConnectionSize\", Integer.class));
        dataSource.setConnectProperties(environment.getProperty(\"spring.datasource.connectionProperties\", Properties.class));
        try {
            dataSource.setFilters(environment.getProperty(\"spring.datasource.filters\"));
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return dataSource;
    }


    @Bean
    public SqlSessionFactory mySqlSessionFactory(@Qualifier(\"myDatasource\") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(dataSource);
        return sqlSessionFactoryBean.get ();
    }


    @Bean
    public SqlSessionTemplate mySqlSessionTemplate(@Qualifier(\"mySqlSessionFactory\") SqlSessionFactory sqlSessionFactory) {
        SqlSessionTemplate sqlSessionTemplate = new SqlSessionTemplate(sqlSessionFactory);
        return sqlSessionTemplate;
    }

 注意配置类中的属性注入时小心不要和配件文件对应错了。之前因为不小心把setMaxWait（environment.getProperty(\"spring.datasource.maxActive\", Integer.class)），导致连接池在没有达到最大连接数时就经常报获取不到连接异常。一个手误查了好久才查到。