spring 注解空指针错误

先贴异常吧：
[code="java"]cn.buct.inteWeb.user.web.LoginAction.login(LoginAction.java:52)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
java.lang.reflect.Method.invoke(Unknown Source)
com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:440)
com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:279)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:242)
com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:163)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:249)
org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:93)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:128)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.ProfilingActivationInterceptor.intercept(ProfilingActivationInterceptor.java:104)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:148)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:128)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:468)
org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:76)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
java.lang.Thread.run(Unknown Source)[/code]

下面是代码
[code="java"]
package cn.buct.inteWeb.user.web;

import javax.annotation.Resource;

import org.apache.commons.lang.StringUtils;

import cn.buct.inteWeb.common.web.AbstractAjaxAction;
import cn.buct.inteWeb.user.entity.User;
import cn.buct.inteWeb.user.service.UserManager;

import cn.buct.inteWeb.Constants;
import cn.buct.inteWeb.SessionHolder;

public class LoginAction extends AbstractAjaxAction {
private static final long serialVersionUID = 1L;

private UserManager userManager;

private static final String USER_LOGIN = "index";

private String userName;
private String password;
private String message;

public String login() {
    String userName2 = getRequest().getParameter("userName");
    System.out.println("userName=" + userName2);
    String password2 = getRequest().getParameter("password");
    System.out.println("password=" + password2);
    System.out.println(userManager);
    /**
     * 判断当前是否已经登录
     */
    if(SessionHolder.isLogined(getRequest())) {
        return USER_LOGIN;
    }
    /**
     * 登录验证码显示控制begin
     */
    long count = 1;
    if (null != getRequest().getSession()
            && null != getRequest().getSession().getAttribute("count")) {
        count = ((Long) getRequest().getSession().getAttribute("count")) + 1;
    }
    getRequest().getSession().setAttribute("count", count);
    if (StringUtils.isBlank(userName) 
            && StringUtils.isNotBlank(getRequest().getParameter("userName"))) {
        userName = getRequest().getParameter("userName").trim();
    }
    // 判断用户是否存在
    User user = userManager.getByName(userName);
    if (user == null) {
        message = Constants.LOGIN_USER_ERROR_MSG;
        return USER_LOGIN;
    }


    return null;
}

public String loginInput() {
    return USER_LOGIN;
}

@Override
protected BaseEntityManager<User, Long> getManager() {
    // TODO Auto-generated method stub
    return null;
}

@Override
protected Long getId() {
    // TODO Auto-generated method stub
    return null;
}   

public void setUserManager(UserManager userManager) {
    this.userManager = userManager;
}

public String getUserName() {
    return userName;
}

public void setUserName(String userName) {
    this.userName = userName;
}
public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

}
[/code]

web.xml文件：
[code="xml"]
<?xml version="1.0" encoding="UTF-8"?>
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
test

index.html
index.htm
index.jsp
default.html
default.htm
default.jsp

contextConfigLocation

classpath*:spring/applicationContext.xml
classpath*:spring/modules/applicationContext*.xml
classpath*:spring/modules/applicationContext-dnsis-soa.xml


org.springframework.web.context.ContextLoaderListener



encodingFilter

org.springframework.web.filter.CharacterEncodingFilter

encoding
UTF-8

encodingFilter
/*



struts2

org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter

actionPackages
cn.buct

struts2
.action

struts2
.jsp

20

[/code]
struts.xml
[code="xml"]
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">

<package name="user" extends="struts-default" namespace="/user">
    <action name="Login" class="cn.buct.inteWeb.user.web.LoginAction">
        <result name="index">/view/user-login.jsp</result>
    </action>
</package>

[/code]

applicationContext.xml
[code="xml"]
<?xml version="1.0" encoding="UTF-8"?>
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:jee="http://www.springframework.org/schema/jee"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
http://www.springframework.org/schema/jee
http://www.springframework.org/schema/jee/spring-jee-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd"
default-lazy-init="true" default-autowire="byName">

<bean
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
    lazy-init="false">
    <property name="systemPropertiesModeName"
        value="SYSTEM_PROPERTIES_MODE_NEVER" />
    <property name="ignoreResourceNotFound" value="true" />
    <property name="order" value="1" />
    <property name="ignoreUnresolvablePlaceholders" value="true" />
    <property name="locations">
        <list>
            <value>classpath:application.properties</value>
        </list>
    </property>
</bean>


<!-- 使用annotation 自动注册bean,并检查@Required,@Autowired的属性已被注入 -->
<context:component-scan base-package="cn.knet" />
<!-- 使用aop定义事务 -->
<bean id="txManager"
    class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource" ref="dataSource" />
</bean>
<aop:config proxy-target-class="true">
    <aop:advisor
        pointcut="execution(* cn.knet.dnsis.*.service.*.*(..))"
        advice-ref="txAdvice" />
</aop:config>

<tx:advice id="txAdvice" transaction-manager="txManager">
    <tx:attributes>
        <tx:method name="get*" read-only="true" />
        <tx:method name="find*" read-only="true" />
        <tx:method name="select*" read-only="true" />
        <tx:method name="*" />
    </tx:attributes>
</tx:advice>
<bean
    class="org.springframework.beans.factory.annotation.RequiredAnnotationBeanPostProcessor" />

<bean id="dataSource"
    class="org.apache.commons.dbcp.BasicDataSource"
    destroy-method="close">
    <property name="driverClassName"
        value="${jdbc.driverClassName}" />
    <property name="url" value="${jdbc.url}" />
    <property name="username" value="${jdbc.username}" />
    <property name="password" value="${jdbc.password}" />
    <property name="maxActive" value="30" />
</bean>
<bean id="sqlMapClient"
    class="org.springframework.orm.ibatis.SqlMapClientFactoryBean">
    <property name="configLocation"
        value="classpath:ibatis/SqlMapConfig.xml" />
</bean>
<bean id="sqlMapClientTemplate"
    class="org.springframework.orm.ibatis.SqlMapClientTemplate" />


<!-- freemarker template engine -->
<bean id="templateEngine"
    class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
    <property name="freemarkerSettings">
        <props>
            <prop key="template_update_delay">0</prop>
            <prop key="default_encoding">UTF-8</prop>
            <prop key="locale">zh_CN</prop>
        </props>
    </property>
</bean>

[/code]

麻烦多指教了。

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也许世界还没停 2011-06-09 08:52
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[quote]问题补充：

ymmihw 写道
userManager == null？

是啊呵呵 [/quote]

是不是LoginAction这个bean注入有问题？

本回答被题主选为最佳回答 , 对您是否有帮助呢?

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spring 注解 空指针错误

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spring 注解空指针错误

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