java - 突然我的 spring.xml 不会实例化我的类并且发生错误异常

Question

我遇到了一个我无法理解的奇怪错误......当我运行我的 web 项目时......我的 jsp 显示出来了。但是点击提交底部后，它挂起然后错误结果。我无法理解我做错了什么......这就像 3 小时试图检查我的问题。但现在我需要一些帮助.. 谢谢大家。

Unable to instantiate Action, lotmovement.action.RegisterAction,  defined for 'register' in namespace '/'Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'registeraction' defined in class path resource [spring.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [lotmovement.action.RegisterAction]: Constructor threw exception; nested exception is org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from class path resource [spring.xml]; nested exception is java.lang.StackOverflowError
    org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:115)
    org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:61)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:877)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:839)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:440)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
    java.security.AccessController.doPrivileged(Native Method)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
    org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
    org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
    org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
    org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:429)
    org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:728)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:380)
    org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    lotmovement.action.RegisterAction.<init>(RegisterAction.java:27)
    sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    java.lang.reflect.Constructor.newInstance(Constructor.java:525)
    java.lang.Class.newInstance0(Class.java:372)
    java.lang.Class.newInstance(Class.java:325)
    com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:131)
    com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:162)
    com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:151)
    com.opensymphony.xwork2.ObjectFactory.buildAction(ObjectFactory.java:121)
    com.opensymphony.xwork2.DefaultActionInvocation.createAction(DefaultActionInvocation.java:300)
    com.opensymphony.xwork2.DefaultActionInvocation.init(DefaultActionInvocation.java:400)
    com.opensymphony.xwork2.DefaultActionProxy.prepare(DefaultActionProxy.java:194)
    org.apache.struts2.impl.StrutsActionProxy.prepare(StrutsActionProxy.java:63)
    org.apache.struts2.impl.StrutsActionProxyFactory.createActionProxy(StrutsActionProxyFactory.java:39)
    com.opensymphony.xwork2.DefaultActionProxyFactory.createActionProxy(DefaultActionProxyFactory.java:58)
    org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:501)
    org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:432)

在tomcat服务器上，这不断重复..

Nov 26, 2012 3:10:51 PM org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
INFO: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@2d43b35f: defining beans [userprofile,registeraction,insertuserprofile,entitystart,recordexistuserprofile]; root of factory hierarchy
Nov 26, 2012 3:10:51 PM org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
INFO: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@50016db: defining beans [userprofile,registeraction,insertuserprofile,entitystart,recordexistuserprofile]; root of factory hierarchy
Nov 26, 2012 3:10:51 PM org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
INFO: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@7ef1277f: defining beans [userprofile,registeraction,insertuserprofile,entitystart,recordexistuserprofile]; root of factory hierarchy
Nov 26, 2012 3:10:51 PM org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
INFO: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@3d510eb6: defining beans [userprofile,registeraction,insertuserprofile,entitystart,recordexistuserprofile]; root of factory hierarchy
Nov 26, 2012 3:10:51 PM org.springframework.beans.factory.support.DefaultSingletonBeanRegistry destroySingletons
INFO: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@66893099: defining beans [userprofile,registeraction,insertuserprofile,entitystart,recordexistuserprofile]; root of factory hierarchy
Nov 26, 2012 3:17:59 PM org.apache.catalina.startup.HostConfig checkResources
INFO: Undeploying context [/LotMovement_5spingtest]

这是我的 XML 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"
       xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd">

    <bean id="userprofile"  class="lotmovement.business.entity.UserProfile">

    </bean>

    <bean id="registeraction"  class="lotmovement.action.RegisterAction">

    </bean>  

    <bean id="insertuserprofile"  
          class="lotmovement.business.crud.InsertUserProfile">

    </bean>


    <bean id="entitystart"  
          class="lotmovement.business.crud.EntityStart">

    </bean>

    <bean id="recordexistuserprofile"  
           class="lotmovement.business.crud.RecordExistUserProfile">

    </bean>


</beans>

这是我的一些代码..

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package lotmovement.action;

import com.opensymphony.xwork2.ActionSupport;
import lotmovement.business.crud.EntityStart;
import lotmovement.business.crud.InsertUserProfile;
import lotmovement.business.crud.RecordExistUserProfile;
import lotmovement.business.entity.UserProfile;
import org.apache.commons.lang3.StringUtils;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 *
 * @author god-gavedmework
 */
public class RegisterAction extends ActionSupport {

    private static String userId;
    private static String password;
    private static String firstName;
    private static String lastName;
    private static int securityLevel;
    ApplicationContext context =
            new ClassPathXmlApplicationContext("spring.xml");
    EntityStart es = (EntityStart) context.getBean("entitystart");

    @Override
    public void validate() {
        es.StartDbaseConnection();
        RecordExistUserProfile reup =
                (RecordExistUserProfile) context.getBean("recordexistuserprofile");
        if (reup.checkrecordexist()) {
            addActionError("record already exist.");
        }
    }

    @Override
    public String execute() {



        InsertUserProfile iup =
                (InsertUserProfile) context.getBean("insertuserprofile");



        iup.Insert();


        return SUCCESS;
    }

这是我的 WEB.XML

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
    <filter>
        <filter-name>struts2</filter-name>
        <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>struts2</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
    <welcome-file-list>
        <welcome-file>register.jsp</welcome-file>
    </welcome-file-list>
</web-app>

Answer 1

您正在 RegisterAction 中使用此行创建无限循环

ApplicationContext context =
        new ClassPathXmlApplicationContext("spring.xml");

循环是你调用 Spring Container，它创建一个 RegisterAction，它（如上所示）创建一个 Spring Container，它创建一个 RegisterAction....

您不应该直接在 Spring Bean 中引用 ApplicationContext。您应该使用配置（setter 或构造函数注入）来设置 bean 的依赖关系。你需要这样做

春天.xml

<bean id="insertUserProfile" class="lotmovement.business.crud.InsertUserProfile"/>

<bean id="registeraction"  class="lotmovement.action.RegisterAction">
  <property name="insertUserProfile" ref="insertUserProfile"/>
</bean>  

然后将方法 setInsertUserProfile 添加到 RegisterAction。Spring 将从您的上下文中使用指定的 bean 调用 setter（在这种情况下，是一个新的 insertUserProfile）。您需要对从上下文中引用的所有 bean 执行此操作。

您可能想对 Spring 构造函数注入进行一些研究，因为它是注入永远不需要更改的依赖项的“更好”方式。

Answer 2

杰夫的回答很到位。这是对什么是错的和你不应该做什么的一个很好的解释。

您缺少的部分是在 web.xml 中注册应用程序上下文：

使用 web.xml 在 Spring 中加载上下文

这是一个更正，加上杰夫的建议，应该让你上路。

Answer 3

为什么在使用 Struts 2 时要自己处理 Spring 容器？您需要 Struts 2 Spring 插件。

http://struts.apache.org/2.3.4.1/docs/spring-plugin.html

虽然其他答案很好并且完美地描述了此代码的问题，但我不确定它们是否是最佳答案。. . Struts 2 提供了 Spring 集成，该集成完全设计为允许您将依赖项无缝地注入到您自己的对象和核心框架对象中，例如操作。

使用 Spring 插件，您可以使用 XML 或注释简单地配置您的 spring bean，仅此而已。Spring 容器集成到框架的核心对象工厂中，这意味着您不必处理它；正是这个问题的代码中对容器的处理为 toksis 带来了问题。