Question

我的代码库中有一个控制器，其包不是组件扫描的。此控制器也未在任何XML中的bean中定义。

不知何故，控制器正在工作。我猜这是因为有一些方法可以在Spring中定义一个控制器而无需组件扫描或在bean中定义它。但是，此控制器实现了一个名为AbstractControllerImpl的类，并且Helper实现类IS正在扫描组件。

Helper是否正在扫描组件这一事实是否意味着Controller也会被扫描？或者如果没有，该控制器如何工作？

@Controller
@RequestMapping("/something")
public class SomeController extends AbstractControllerImpl<SomeControllerHelper> {  
    //Some request mappings here
}

它扩展的抽象控制器类：

public abstract class AbstractControllerImpl<H extends Helper>
    implements Controller<H>
{    
    private H helper;    

    private BaseValidator validator;

    public H getHelper()
    {
        return helper;
    }

    public void setHelper(H helper)
    {
        this.helper = helper;
    }   

    public void setValidator(BaseValidator validator)
    {
        this.validator = validator;
    }

    public BaseValidator getValidator()
    {
        return validator;
    }

    public Errors doValidation(Object obj)
    {
        Errors validationErrors = new BindException(this, "");
        if (validator != null)
        {
            validator.validate(obj, validationErrors);
        }
        return validationErrors;
    }   
}

Controller接口：

public interface Controller<H extends Helper>
{
    H getHelper();
}

助手定义：

<?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-3.0.xsd">


   <bean id="someHelper" class="com.controller.SomeHelperImpl" />   

</beans>

helper impl类（正在扫描组件）：

@Component("SomeControllerHelper")
public class ASomeControllerHelperImpl implements SomeControllerHelper {
    //Some methods here
}

编辑：我的web.xml。我删除了一些servlet映射并更改了一些名称，但这就是它的样子：

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4" 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">
    <display-name>SomeApp</display-name>

<welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
</welcome-file-list>

<listener>
    <listener-class>
        com.Log4jLoaderServlet
    </listener-class>
</listener>

<context-param>
    <param-name>crossContext</param-name>
    <param-value>true</param-value>
</context-param>

<!-- This listener will load other application context file in addition to springweb-servlet.xml -->
<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- The context params that read by ContextLoaderListener  -->
<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/spring/root-application-context.xml</param-value>
</context-param>
<!-- Spring security filter -->
<filter>
    <filter-name>springSecurityFilterChain</filter-name>
    <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>

<filter-mapping>
    <filter-name>springSecurityFilterChain</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping> 

<listener>
    <listener-class>
        org.springframework.web.context.request.RequestContextListener
    </listener-class>
</listener>

<servlet>
    <servlet-name>rest</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/spring/servlets/rest-servlet.xml</param-value>
    </init-param>       
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>rest</servlet-name>
    <url-pattern>/service/*</url-pattern>
</servlet-mapping>

<servlet>
    <servlet-name>appservlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/spring/servlets/app-servlet.xml</param-value>
    </init-param>       

    <load-on-startup>1</load-on-startup>
</servlet>

<error-page>
    <error-code>404</error-code>        
    <location>/portal/error/notfound/</location>
</error-page>

<error-page>
    <error-code>500</error-code>
    <location>/portal/error/internalsystem/</location>
</error-page>

<jsp-config>
    <taglib>
        <taglib-uri>http://java.sun.com/jsp/jstl/core</taglib-uri>
        <taglib-location>/WEB-INF/tags/c.tld</taglib-location>
    </taglib>
    <taglib>
      <taglib-uri>http://jakarta.apache.org/taglibs/unstandard-1.0</taglib-uri>
      <taglib-location>/WEB-INF/tld/unstandard.tld</taglib-location>
    </taglib>
</jsp-config>

这是app-servlet.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:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    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">


    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.UrlBasedViewResolver">
        <property name="viewClass" value="org.springframework.web.servlet.view.tiles2.TilesView" />
        <property name="order" value="0" />
    </bean>

    <bean id="jspViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"/>
        <property name="order" value="1" />
    </bean> 

    <bean  class="org.springframework.web.servlet.view.ResourceBundleViewResolver">

        <property name="basename" value="views"/>
    </bean>

    <bean id="tilesConfigurer"
        class="org.springframework.web.servlet.view.tiles2.TilesConfigurer">
            <property name="definitions">
                <list>                                 
                    <value>/WEB-INF/views/something/views.xml</value>
                    <value>/WEB-INF/views/views.xml</value>
                </list>
            </property>
            <property name="preparerFactoryClass"
                value="org.springframework.web.servlet.view.tiles2.SpringBeanPreparerFactory"/>
    </bean>     
</beans>

休息-servlet.xml中：

<?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"
    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">

    <context:component-scan base-package="com.dw.spring3.rest.controller" />
    <!-- To enable @RequestMapping process on type level and method level -->
    <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" />
    <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <ref bean="jsonConverter" />
            </list>
        </property>
    </bean>

    <bean id="jsonConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
        <property name="supportedMediaTypes" value="application/json" />
    </bean>

</beans>

根应用cnntext.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:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    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">
    <context:component-scan
        base-package="com.base.notcontroller" />

    <import resource="/something/common-context.xml" />          
</beans>

Answer 1

Helper正在扫描组件的事实是否意味着控制器也被扫描了？或者如果没有，这怎么可能呢控制器有效吗？

不，这是不可能的。

鉴于您已经

，您的上下文配置看起来并不完全清楚

删除了一些servlet映射并更改了一些名称

但是你的@Controller类必须加载到某个上下文中，可能在

中

rest-servlet.xml:

有

<context:component-scan base-package="com.dw.spring3.rest.controller" />

由名为DispatcherServlet的{{1}}加载。

`rest

您可以在<servlet> <servlet-name>rest</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/spring/servlets/rest-servlet.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet>类中添加一个无参数构造函数并放入一个断点，查看堆栈跟踪并确定它在哪个上下文中被初始化。

请注意，{3.2}已弃用@Controller。考虑使用AnnotationMethodHandlerAdapter配置MVC环境。

控制器定义没有组件扫描或bean定义

1 个答案: