SpringMVC Druid链接池配置使用

    此次在项目中遇到了一个奇怪的问题, 就是在每隔一段时间访问服务器就会报链接超时的错误,但在次请求就不会出现该问题,刚开始觉得是服务器那边数据库的问题,可是发现其余项目中都没有这种问题,因此查了好久发现原来是数据链接池这块的相关参数根本没有配置,这才致使出现的这样的错误,耽搁的这么长时间;都怪我太大意,因此写下来这个错误,下次就不要在犯了;

    这里推荐一个很好用的数据链接池:

<dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.0.29</version>
    </dependency>

string-mybatis.xml中相关配置:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	   xmlns:p="http://www.springframework.org/schema/p"
	   xmlns:tx="http://www.springframework.org/schema/tx"
	   xmlns:context="http://www.springframework.org/schema/context"
	   xmlns:aop="http://www.springframework.org/schema/aop"
	   xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/tx
    http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context-3.0.xsd
    http://www.springframework.org/schema/aop 
    http://www.springframework.org/schema/aop/spring-aop-3.0.xsd ">
    <context:component-scan base-package="com.xt.shop.base.service.impl" />
	<context:annotation-config />
	<tx:annotation-driven />

	<!-- 读取JDBC的配置-->
	<bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="locations" value="classpath:jdbc.properties"/>
	</bean>
	<!-- 配置数据源，从上面配置文件读取-->
	<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
		<property name="url" value="${jdbc.url}" />
		<property name="username" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}" />
		
		<!--==============DRUID链接池相关配置==================-->
		
		<!--初始化时创建物理链接的个数-->
        <property name="initialSize" value="5"/>
		<!--最小链接池数量-->
        <property name="minIdle" value="10"/>
		<!--最大链接池数量-->
        <property name="maxActive" value="100"/>
		<!--链接时最大等待时间,单位毫秒-->
        <property name="maxWait" value="60000"/>
		<!--配置间隔多久才进行一次检测,检测须要关闭的空闲链接,单位是毫秒-->
        <property name="timeBetweenEvictionRunsMillis" value="60000"/>
		<!--配置一个链接在池中最小生存的时间,单位是毫秒-->
        <property name="minEvictableIdleTimeMillis" value="300000"/>
		<!--用来检测链接是否有效的SQL,要求是一个查询语句-->
        <property name="validationQuery" value="SELECT 1 FROM DUAL"/>
		<!--申请链接时执行 validationQuery 检测链接是否有效,作了这个配置会下降性能-->
        <property name="testOnBorrow" value="true"/>
		<!--归还链接时执行 validationQuery 检测链接是否有效,作了这个配置会下降性能-->
        <property name="testOnReturn" value="true"/>
		<!--建议配置为true,不影响性能,而且保证安全性;申请链接的时候检测,若是空闲时间大于
			timeBetweenEvictionRunsMillis,执行 validationQuery 检测链接是否有效-->
        <property name="testWhileIdle" value="true"/>
        <!--是否缓存preparedStatement,也就是 PSCache-->
        <property name="poolPreparedStatements" value="true"/>
        <!--指定每一个链接上 PSCache 的大小-->
        <property name="maxOpenPreparedStatements" value="20"/>
        <!-- 打开清除废弃链接功能 -->  
        <property name = "removeAbandoned" value = "true"/>  
        <!--清除废弃链接的超时时间-->
        <property name="removeAbandonedTimeout" value="1800"/>
        <!-- 关闭 清除 链接时输出错误日志 -->     
        <property name = "logAbandoned" value = "true"/> 
        <!--配置监控统计拦截的filters,属性类型是字符串,经过别名的方式配置扩展插件,
        	经常使用的插件有:监控统计用的STAT;日志用的log4j;防护SQL注入的wall-->
        <property name="filters" value="stat,wall,log4j"/>
        <!--经过 connectProperties 属性来打开mergeSql功能；慢SQL记录-->
        <property name="connectionProperties" value="druid.stat.merggSql=ture;druid.stat.slowSqlMillis=5000"/>
        <!--合并多个DruidDataSource的监控数据-->
        <property name="useGlobalDataSourceStat" value="true"/>
	</bean>
	
	<!-- MyBatis_Plus配置: -->
	<bean id="sqlSessionFactory" class="com.baomidou.mybatisplus.spring.MybatisSqlSessionFactoryBean">
		<property name="dataSource" ref="dataSource"/>
		<!-- 配置扫描实体的包路径 -->
		<property name="typeAliasesPackage" value="com.xt.shop.base.entity"/>
		<!-- 配置扫描 MAPPER XML的位置 -->
		<property name="mapperLocations" value="classpath:mybatis/mapper/*.xml"/>
		<!-- 配置 MyBatis配置文件的位置 -->
		<property name="configLocation" value="classpath:mybatis/mybatis-config.xml"/>
		<property name="globalConfig" ref="globalConfig"/>
		<!-- 配置插件 -->
		<property name="plugins">
            <array>
                <!-- 分页插件配置 -->
                <bean id="paginationInterceptor" class="com.baomidou.mybatisplus.plugins.PaginationInterceptor">
                    <property name="dialectType" value="mysql"/>
                    <property name="optimizeType" value="aliDruid" />
                </bean>
            </array>
        </property>
	</bean>
	
    <!-- MP 全局配置注入 -->
    <bean id="globalConfig" class="com.baomidou.mybatisplus.entity.GlobalConfiguration">
        <property name="idType" value="0"/>
        <property name="dbColumnUnderline" value="true"/>
    </bean>
    
	<!-- 配置扫描MAPPER接口的包路径 -->
	<bean id="mapperScannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer">
		<property name="basePackage" value="com.xt.shop.base.mapper"/>
		<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
	</bean>
	
  	<!-- 事务处理  -->
    <bean id= "transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
		<property name="dataSource" ref="dataSource"/>
	</bean>
	
	<!-- 事务注解:开启注解支持-->
    <tx:annotation-driven transaction-manager="transactionManager" proxy-target-class="true"/>
    
    <!-- 全局AOP事物,除get,list,select,query开头的方法外,都处在事物当中  -->
	<tx:advice id="txAdvice" transaction-manager="transactionManager">
		<tx:attributes>
			<tx:method name="select*" propagation="REQUIRED" read-only="true" />
			<tx:method name="get*" propagation="REQUIRED" read-only="true" />
			<tx:method name="list*" propagation="REQUIRED" read-only="true" />
			<tx:method name="query*" propagation="REQUIRED" read-only="true" />
			<tx:method name="*" propagation="REQUIRED" read-only="false" rollback-for="java.lang.Exception"/>
		</tx:attributes>
	</tx:advice>
	
	<!-- 配置事务切面 到Service层 -->
	<aop:config expose-proxy="true" proxy-target-class="true" >
		<aop:advisor advice-ref="txAdvice" pointcut="execution(* com.xt.shop.base.service..*.*(..))"/>
	</aop:config>
  
</beans>

web.xml中相关配置:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring/spring-mybatis.xml</param-value>
  </context-param>
  <listener>
    <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
  </listener>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <filter>
    <filter-name>SetCharacterEncoding</filter-name>
    	<filter-class>
			com.xt.shop.base.interceptor.SimpleCORSFilter
		</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
    <init-param>
      <param-name>forceEncoding</param-name>
      <param-value>true</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>SetCharacterEncoding</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  <servlet>
    <servlet-name>Spring MVC</servlet-name>
    <servlet-class>
			org.springframework.web.servlet.DispatcherServlet
		</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:spring/spring-mvc.xml</param-value>
    </init-param>
    <load-on-startup>2</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>Spring MVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

    <filter>
        <filter-name>DruidWebStatFilter</filter-name>
        <filter-class>com.alibaba.druid.support.http.WebStatFilter</filter-class>
        <init-param>
            <param-name>exclusions</param-name>
            <param-value>/static/*,*.ico,/druid/*</param-value>
        </init-param>
        <init-param>
            <param-name>sessionStatEnable</param-name>
            <param-value>false</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>DruidWebStatFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--===================DRUID监控====================-->
    <servlet>
        <servlet-name>DruidStatView</servlet-name>
        <servlet-class>com.alibaba.druid.support.http.StatViewServlet</servlet-class>
        <init-param>
            <!-- 用户名 -->
            <param-name>loginUsername</param-name>
            <param-value>admin</param-value>
        </init-param>
        <init-param>
            <!-- 密码 -->
            <param-name>loginPassword</param-name>
            <param-value>admin</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>DruidStatView</servlet-name>
        <url-pattern>/druid/*</url-pattern>
    </servlet-mapping>
</web-app>

这样就能够在该服务器下  /druid 中访问 Druid 中拦截到的信息了;

参考: http://blog.csdn.net/hj7jay/article/details/51686418