SSM框架中自己写了一个工具包，在此包得类中注入Mapper接口是null，
0
[已解决问题]
解决于 2018-05-07 11:33
这是工具类
这是定时任务包
是在定时包中调用工具类里得方法来处理数据库数据，
在工具类中需要注入Mapper接口来操作数据库，但注入得是null；
public class Close_data { @Autowired public CategoryMapper categoryMapper; public void delete() { System.out.println("categoryMapper : "+categoryMapper); //类别偏好 categoryMapper.delete1(); //借还书信息，评分 categoryMapper.delete2(); //聚类号，分组 categoryMapper.delete3(); //邻居信息 categoryMapper.delete4(); //创建借还书表信息，评分初始化为0 categoryMapper.add1(); } }
用tomcat启动后报的错误信息
我打印了下mapper是null
categoryMapper : null ERROR [scheduler-1] - Unexpected error occurred in scheduled task. java.lang.NullPointerException at com.how2java.tools.Close_data.delete(Close_data.java:18) at com.how2java.job.TimerTask.test2(TimerTask.java:36) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.springframework.scheduling.support.ScheduledMethodRunnable.run(ScheduledMethodRunnable.java:64) at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:53) at org.springframework.scheduling.concurrent.ReschedulingRunnable.run(ReschedulingRunnable.java:81) at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source) at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source)
问题补充：
配置信息applicationContext.xml
配置信息web.xml
配置信息spring-task.xml
<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-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/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd"> <context:annotation-config /> <context:component-scan base-package="com.how2java.service,com.how2java.mapper" /> <!--<context:component-scan base-package="com.how2java" /> --> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName"> <value>com.mysql.jdbc.Driver</value> </property> <property name="url"> <value>jdbc:mysql://localhost:3306/library?characterEncoding=UTF-8</value> </property> <property name="username"> <value>root</value> </property> <property name="password"> <value>admin</value> </property> </bean> <bean id="sqlSession" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="typeAliasesPackage" value="com.how2java.pojo" /> <property name="dataSource" ref="dataSource"/> <property name="mapperLocations" value="classpath:com/how2java/mapper/*.xml"/> </bean> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.how2java.mapper"/> </bean> </beans>
<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-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/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd"> <context:annotation-config/> <context:component-scan base-package="com.how2java.controller"> <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/> </context:component-scan> <mvc:annotation-driven > <mvc:message-converters register-defaults="true"> <bean class="org.springframework.http.converter.StringHttpMessageConverter"> <property name="supportedMediaTypes" value="text/plain;charset=UTF-8" /> </bean> </mvc:message-converters> </mvc:annotation-driven> <mvc:default-servlet-handler /> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" /> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> </bean> </beans>
<?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" xmlns:web="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_2_5.xsd" version="2.5"> <!-- spring的配置文件--> <context-param> <param-name>contextConfigLocation</param-name> <param-value> classpath:applicationContext.xml classpath:spring-task.xml </param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <!-- spring mvc核心：分发servlet --> <servlet> <servlet-name>mvc-dispatcher</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <!-- spring mvc的配置文件 --> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:springMVC.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>mvc-dispatcher</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> </web-app>
<?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:context="http://www.springframework.org/schema/context" xmlns:task="http://www.springframework.org/schema/task" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-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/task http://www.springframework.org/schema/task/spring-task-3.0.xsd" default-autowire="byName" default-lazy-init="false"> <!--配置包扫描--> <context:component-scan base-package="com.how2java.job" /> <!-- 定时任务配置 scheduler 方式 注解 --> <task:executor id="executor" pool-size="5"/> <task:scheduler id="scheduler" pool-size="10"/> <task:annotation-driven executor="executor" scheduler="scheduler"/> </beans>
最佳答案
0
你的CategoryMapper 所在包有没有被扫描？类似于这种配置
<mybatis:scan base-package="mapper所在包路径" />
奖励园豆：5
写了呀，我把那个配置文件也上传了，第一个，你点展开看看，，我怀疑是spring配置文件加载问题.junit单元测试可以，
@窦光大大存大大凯: 你这个tools所在的包应该也要被扫描的把，不然他也是没办法注入的
@让我发会呆: 试了下，不行，还是空
@窦光大大存大大凯: 我本地试了下，再工具类里确实没办法用注解的方式注入mapper，我现在也不知道是哪儿配置有问题，但是你可以试试这种方式注入：
SpringApplicationContext.getApplicationContext().getBean(CategoryMapper.class)
@窦光大大存大大凯: https://www.cnblogs.com/acm-bingzi/p/springBean.html,看看这篇文章，应该能理解了。
@让我发会呆: 谢谢了，好像是这样得，但是你这个SpringApplicationContext，我是没法用的，这是springboot吗，我是根据你的提议，百度如何解决多线程时Autowired自动注入问题，https://blog.csdn.net/u011493599/article/details/78522315，，解决了 谢谢了 ，非常感谢！
@让我发会呆: 谢谢
@窦光大大存大大凯: 这个SpringApplicationContext就是Spring，不是springboot，我系统中封装了一层，其实就是ApplicationContext.getBean(beanName);
