spring注入不进去是什么原因啊

public class StuAction extends ActionSupport{
private StuService stuService ;

private int id;
private String name;

public StuService getStuService() {
System.out.println("对象注入1");
System.out.println(stuService);
return stuService;
}
public void setStuService(StuService stuService) {
System.out.println("对象注入2");
System.out.println(stuService);
this.stuService = stuService;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
这里是action里面的set方法，结果运行程序的时候报错空指针，他不运行！这是什么原因？
ssh框架结合，运行的时候stuService 是null
-----------------------------------------------------------------------------------------------------------------------这里是配置文件
<?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: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/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
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd">
<context:annotation-config></context:annotation-config>

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver">
</property>
<property name="url" value="jdbc:mysql://localhost:3306/test"></property>
<property name="username" value="root"></property>
<property name="password" value="root"></property>
</bean>
<bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="dataSource">
<ref bean="dataSource" />
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.MySQLDialect
</prop>
</props>
</property>
<property name="mappingResources">
<list>
<value>model/Stu.hbm.xml</value>
</list>
</property>
</bean>
<bean name="StuDAO" class="dao.StuDAO">
<property name="sessionFactory">
<ref bean="sessionFactory" />
</property>
</bean>
<bean name="stuService" class="service.StuService">
<property name="stuDao" ref="StuDAO" />
</bean>
<bean name="Stu" class="action.StuAction">
<property name="stuService" ref="stuService" />
</bean>
</beans>
--------------------------------------------------------------------------------------------这里是web
<?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/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/classes/applicationContext*.xml
</param-value>
</context-param>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<welcome-file-list>
<welcome-file>login.jsp</welcome-file>
</welcome-file-list>
<login-config>
<auth-method>BASIC</auth-method>
</login-config>
</web-app>

7 个解决方案

#1

报错信息，如果程序可以启动，也可以自己debug

#2

stuService 初始化好了吗？
它的源码发发看

#3

求截图错误信息

#4

你那个stuService的bean中，class要写实现类（stuServiceImpl），你写的是接口（stuService），肯定不行了

#5

要理解的方式，一种是根据set方法，那么要求Service是标准的javabean。
别一种则是能过属性注入。一这下要区分，不要先急着注入，先理解一个他的注入方式。

#6

这个bean <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">

id 应该是 “sqlSessionFactory” id 的命名一般是类名的首字母小写

#7

你在applicationContext中配置的bean中，所有的class都必须是接口的实现类！

#1