IDEA——SSM配置笔记（附带Illegal access: this web application instance has been stopped already. Could not load [].解决方案）

  • 首先简单理解Spring容器和SpringMVC的关系
    • web.xml中spring的核心ContextLoaderListener初始化的上下文和springmvc的核心DispatcherServlet初始化的上下文关系:
    • Spring容器和SpringMVC容器虽然是父容器与子容器的关系，但二者之间具有一定的独立性。具体来说，两个容器基于各自的配置文件分别进行初始化，只有在子容器找不到对应的Bean时，才回去父容器中去找并加载。

    • 此外，一般地，SpringMVC容器只管理Controller，剩下的Service、Repository 和 Component 由Spring容器去管理，不建议两个容器上在管理Bean上发生交叉。

　　2. 环境搭建

　　　           　

　　　　　　　　　　　　　　　　工程目录如下：

　　　　然后就是部署Tomcat的web运行环境，注意web.xml，applicationContext.xml，spring-mvc.xml中关于路径的配置都是相对于classpath或WEB-INF配置的，因为实际生产环境中可能只有项目运行代码，并没有源文件，运行时需要到web项目下加载文件。

        • 　web.xml 
           1 <?xml version="1.0" encoding="UTF-8"?>
 2 <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
 3          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4          xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
 5          version="4.0">
 6 
 7     <welcome-file-list>
 8         <welcome-file>index.jsp</welcome-file>
 9     </welcome-file-list>
10 
11     <!--    用于加载Spring      -->
12     <listener>
13         <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
14     </listener>
15     <listener>
16         <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
17     </listener>
18 
19     <!--    配置applicationContext.xml文件位置    -->
20     <context-param>
21         <param-name>contextConfigLocation</param-name>
22         <param-value>classpath:config/spring/applicationContext.xml</param-value>
23     </context-param>
24 
25     <!--    加载log4j2    -->
26     <listener>
27         <listener-class>org.apache.logging.log4j.web.Log4jServletContextListener</listener-class>
28     </listener>
29 
30     <!--    配置log4j2.xml文件位置    -->
31     <context-param>
32         <param-name>log4jConfiguration</param-name>
33         <param-value>classpath:config/log/log4j2.xml</param-value>
34     </context-param>
35 
36     <filter>
37         <filter-name>encodingFilter</filter-name>
38         <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
39         <init-param>
40             <param-name>encoding</param-name>
41             <param-value>UTF-8</param-value>
42         </init-param>
43         <init-param>
44             <param-name>forceEncoding</param-name>
45             <param-value>true</param-value>
46         </init-param>
47     </filter>
48     <filter-mapping>
49         <filter-name>encodingFilter</filter-name>
50         <url-pattern>/*</url-pattern>
51     </filter-mapping>
52 
53     <!--    前端控制器配置     -->
54     <servlet>
55         <servlet-name>dispatcher</servlet-name>
56         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
57         <init-param>
58             <param-name>contextConfigLocation</param-name>
59             <param-value>classpath:config/spring/spring-mvc.xml</param-value>
60         </init-param>
61         <load-on-startup>1</load-on-startup>
62     </servlet>
63     <servlet-mapping>
64         <servlet-name>dispatcher</servlet-name>
65         <url-pattern>/</url-pattern>
66     </servlet-mapping>
67 
68     <!--    配置session过期时间（以分为单位）    -->
69     <session-config>
70         <session-timeout>30</session-timeout>
71     </session-config>
72 </web-app>
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        •    applicationContext.xml（applicationContext.xml文件内容如下，主要是配置dataSource （数据源）、事务管理、对dataSource 数据源进行事务管理、事务通知、事务 aop 配置等）
        •  1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4        xmlns:aop="http://www.springframework.org/schema/aop"
 5        xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
 6        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 7                            http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
 8                            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
 9                            http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
10 
11     <description>Spring Configuration</description>
12 
13     <context:component-scan base-package="cn.itcast.ssm.service"/>
14     <context:component-scan base-package="cn.itcast.ssm.mapper"/>
15 
16     <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close"/>
17 
18     <!--    dao层    -->
19     <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
20         <!--   注意在web环境下配置文件位置应设置为WEB-INF中相应的路径      -->
21         <property name="configLocation" value="classpath:config/mybatis/mybatis-config.xml"/>
22         <property name="dataSource" ref="dataSource"/>
23     </bean>
24     <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
25         <property name="basePackage" value="cn.itcast.ssm.mapper"/>
26         <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
27     </bean>
28 
29     <!--    service层    -->
30     <bean id="itemsService" class="cn.itcast.ssm.service.impl.ItemsServiceImpl"/>
31 
32     <!--    事务配置    -->
33     <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
34         <property name="dataSource" ref="dataSource"/>
35     </bean>
36     <tx:advice id="txAdvice" transaction-manager="txManager">
37         <tx:attributes>
38             <tx:method name="insert*" propagation="REQUIRED"/>
39             <tx:method name="save*" propagation="REQUIRED"/>
40             <tx:method name="delete*" propagation="REQUIRED"/>
41             <tx:method name="update*" propagation="REQUIRED"/>
42             <tx:method name="retrieve*" propagation="SUPPORTS" read-only="true"/>
43             <tx:method name="select*" propagation="SUPPORTS" read-only="true"/>
44             <tx:method name="find*" propagation="SUPPORTS" read-only="true"/>
45         </tx:attributes>
46     </tx:advice>
47     <aop:config>
48         <aop:pointcut id="pointcut1" expression="execution(* cn.itcast.ssm.service..*(..))"/>
49         <aop:advisor advice-ref="txAdvice" pointcut-ref="pointcut1"/>
50     </aop:config>
51 </beans>
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        •    spring-mvc.xml（主要是web层，如controller层和视图层的配置） 
           1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4        xmlns:mvc="http://www.springframework.org/schema/mvc"
 5        xmlns:context="http://www.springframework.org/schema/context"
 6        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
 7                            http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
 8                            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
 9 
10     <context:component-scan base-package="cn.itcast.ssm.controller"/>
11 
12     <!--    配置视图解析器     -->
13     <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
14         <property name="prefix" value="/WEB-INF/jsp/"/>
15         <property name="suffix" value=".jsp"/>
16     </bean>
17 </beans>
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　　　　另外，在项目中配置log4j（log4j2）日志是很重要的，对于程序出错时查错，找错，调试有很大帮助，对于上面所提到的（注意web.xml，applicationContext.xml，spring-mvc.xml中关于路径的配置都是相对于classpath或WEB-INF配置的，因为实际生产环境中可能只有项目运行代码，并没有源文件，运行时需要到web项目下加载文件），如果配置的路径不是相对于classpath或者WEB-INF，没配置日志本人实现时抛出如下异常，由于信息量少，很难找出错误所在：

18-Jun-2019 09:26:36.836 信息 [Abandoned connection cleanup thread] org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading Illegal access: this web application instance has been stopped already. Could not load []. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
 java.lang.IllegalStateException: Illegal access: this web application instance has been stopped already. Could not load []. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
	at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading(WebappClassLoaderBase.java:1348)
	at org.apache.catalina.loader.WebappClassLoaderBase.getResource(WebappClassLoaderBase.java:1007)
	at com.mysql.cj.jdbc.AbandonedConnectionCleanupThread.checkContextClassLoaders(AbandonedConnectionCleanupThread.java:96)
	at com.mysql.cj.jdbc.AbandonedConnectionCleanupThread.run(AbandonedConnectionCleanupThread.java:69)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:834)

　　在加了log4j2日志后，显示：

Caused by: java.io.FileNotFoundException: Could not open ServletContext resource [/config/mybatis/mybatis-config.xml]
	at org.springframework.web.context.support.ServletContextResource.getInputStream(ServletContextResource.java:141)
	at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:406)
	at org.mybatis.spring.SqlSessionFactoryBean.afterPropertiesSet(SqlSessionFactoryBean.java:380)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1692)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1630)
	... 81 more

　　

　　从而得知找不到相应配置文件，原因在于配置是相对于src的，而不是相对于classpath，修正后即可正常运行。

　　可见，项目中加入日志是很有帮助的。

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原文地址：https://www.cnblogs.com/Hr666/p/11043540.html