新手贴!一个小错误求大神们帮忙看下!跪谢

蒙逼D路飞 2017-05-05 11:59:52

不浪费大神时间,小弟先简单说下问题.
一个学校的小项目练手的ssh框架.问题出在页面报500空指针错误,原因在24行也就是如下所示!
这是我的Action类,业务类中的增删改查方法我测试过都没问题
package com.Action;
import java.util.List;
import com.opensymphony.xwork2.ActionSupport;
import com.pojo.Animal;
import com.service.AnimalService;

public class AnimalAction extends ActionSupport {
private AnimalService animalService;
private List<Animal> list;

public List<Animal> getList() {
return list;
}
public void setList(List<Animal> list) {
this.list = list;
}
public void setAnimalService(AnimalService animalService) {
this.animalService = animalService;
}
public String home(){
list=animalService.findall();//报空指针的地方
if(list==null){
return ERROR;
}
return "home";
}
}

这是我的struts.xml
<package name="default" namespace="/" extends="struts-default">
<action name="homeaction" class="com.Action.AnimalAction">
<result name="home">/home.jsp</result>
<result name="ERROR">/error.jsp</result>
</action>

这是我的jsp页面
<body>
<table border="1">
<tr>
<td>编号</td>
<td>姓名</td>
<td>品种</td>
<td>年龄</td>
<td>操作</td>
</tr>
<tr>
<s:iterator var="animal" value="list">
<td><s:property value="animal.id"/></td>
<td><s:property value="animal.name"/></td>
<td><s:property value="animal.kind"/></td>
<td><s:property value="animal.age"/></td>
<td colspan="2">
<a href="">删除</a>
<a href="">修改</a>
</td>
</s:iterator>
</tr>
<tr>
<td colspan="6"><a href="">删除</a></td>
</tr>
</table>

...全文

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YouJune 2017-05-08

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不用注解注入要写set方法啊

110成成 2017-05-07

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struts中配置了homeaction 注入<bean id="animalAction" class="com.Action.AnimalAction"> 要保持一致,要配为一致。

lijiafengz 2017-05-07

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applicationcontext.xml缺少注入吧

Yake_Can 2017-05-07

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struts配置文件中action标签是不是要写class 我刚学ssh 不太清楚哈

李德胜1995 2017-05-06

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引用 3 楼 weixin_38665948 的回复:

我感觉好像applicationcontext.xml里少点什么!是不是没有属性注入吗亲?有点晕

applicationcontext.xml贴出来看看。。。。

蒙逼D路飞 2017-05-06

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<?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: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/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd"> <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/mysql"></property> <property name="username" value="root"></property> <property name="password" value="mysql"></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>com/pojo/Animal.hbm.xml</value></list> </property> </bean>  <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory"> <ref bean="sessionFactory"/> </property> </bean> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <tx:attributes>  <tx:method name="add*" propagation="REQUIRED"/> <tx:method name="delete*" propagation="REQUIRED"/> <tx:method name="update*" propagation="REQUIRED"/> <tx:method name="get*" propagation="NOT_SUPPORTED"/> <tx:method name="find*" propagation="NOT_SUPPORTED"/> <tx:method name="*" propagation="REQUIRED"/> </tx:attributes> </tx:advice> <aop:config> <aop:pointcut expression="execution(* com.biz.impl.*.*(..))" id="bizpc"/> <aop:advisor advice-ref="txAdvice" pointcut-ref="bizpc"/> </aop:config> <bean id="animalDao" class="com.dao.impl.DaoImpl"> <property name="sessionFactory"> <ref bean="sessionFactory"/> </property> </bean> <bean id="serviceDao" class="com.service.impl.AnimalServiceImpl"> <property name="dao"> <ref bean="animalDao"/> </property> </bean> <bean id="animalAction" class="com.Action.AnimalAction"> <property name="animalService"> <ref bean="serviceDao"/> </property> </bean>

蒙逼D路飞 2017-05-06

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我感觉好像applicationcontext.xml里少点什么!是不是没有属性注入吗亲?有点晕

蒙逼D路飞 2017-05-06

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错误是这样的 HTTP Status 500 - -------------------------------------------------------------------------------- type Exception report message description The server encountered an internal error () that prevented it from fulfilling this request. exception java.lang.NullPointerException com.Action.AnimalAction.home(AnimalAction.java:24) sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) java.lang.reflect.Method.invoke(Method.java:597) com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:452) com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:291) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:254) com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:263) org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:133) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:207) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:142) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:166) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:190) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248) org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52) org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:485) org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77) org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91) org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) note The full stack trace of the root cause is available in the Apache Tomcat/6.0.13 logs. 全注解的方式老师还没教........

李德胜1995 2017-05-06