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带xml混合问题的Spring注释

annotations spring-mvc spring java

bezmax · 技术社区 · 16 年前

我正在试图找到一个最佳的方法来使用最新的spring3.0。我真的很喜欢@RequestMapping注释及其所有特性。但是,我不喜欢的是,绑定到动作的URL应该在java文件中完全指定。

最好是以某种方式将整个url绑定配置发送到上下文xml文件。不过,如果url绑定至少可以部分地移动到xml,也可以。

这就是我的意思:

当前代码:

@Controller
@RequestMapping("myController")
class MyController {
    @RequestMapping("**/someMethod")
    String someMethod(...) {
    }
}

此代码将myController/somethod绑定到myController::somethod。我不喜欢的是“myController”部分绑定也在这个java文件中。我想让它尽可能的模块化,而这个部分对我来说非常糟糕。

上下文.xml

<mapping>
    <url>myController</url>
    <controller>MyController</controller>
</mapping>

@Controller
//-- No request mapping here --// @RequestMapping("myController")
class MyController {
    @RequestMapping("**/someMethod")
    String someMethod(...) {
    }
}

在Spring3中的带注释的控制器上有这样的功能吗?

3 回复 | 直到 16 年前

Arthur Ronald 16 年前

按要求。你想吗 创建自己的URL模式,而不使用Spring控制器注释 .

首先,创建CustomController注释以避免被@Controller检测到 HandlerMapping

package br.com.ar.web.stereotype;

@Target(value=TYPE)
@Retention(value=RUNTIME)
@Component
public @interface CustomController {}

@CustomController
public class AccountController {

    public void form(Long id) {
        // do something
    }

}

我们的handleAdapter—它负责调用我们的控制器—类似于Spring验证程序接口方法

package br.com.ar.web.support;

public class CustomHandlerAdapter implements HandlerAdapter {

    public boolean supports(Object handler) {
        Annotation [] annotationArray = handler.getClass().getAnnotations();

        for(Annotation annotation: annotationArray) {
           /**
             * Make sure your annotation contains @SomeController
             */
        }
    }

    /**
      * Third parameter is our CustomController
      */
    public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        Method[] methods = handler.getClass().getMethods();

        /**
          * Logic To verify whether Target method fullfil request goes here
          */            

        /**
          * It can be useful To see MultiActionController.invokeNamedMethod and MultiActionController.isHandlerMethod              
          */
        method.invoke(// parameters goes here);
    }

    public long getLastModified(HttpServletRequest request, Object handler) {
        return -1;
    }
}

getApplicationContext().getBean(beanName);

package br.com.ar.web.servlet.handler;

public class CustomeHandlerMapping extends WebApplicationObjectSupport implements HandlerMapping, Ordered {

    private static final String CUSTOM_HANDLER_ADAPTER_NAME = "CUSTOM_HANDLER_ADAPTER_NAME";

    /**
      * Bind each URL path-CustomController bean name
      */
    private final Map handlerMap = new LinkedHashMap();

    /**
      * Ordered interface will make sure your HandlerMapping should be intercepted BEFORE or AFTER DefaultAnnotationHandlerMapping
      */
    public final void setOrder(int order) {
        this.order = order;
    }

    public final int getOrder() {
        return this.order;
    }

    /**
      * HandlerMapping interface method
      */
    public final HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {
        String url = extractUrl(request);

        if(handlerMap.get(url) == null) {
            /**
              * Because Spring 3.0 controller is stateful
              * Let's just store CustomController class (Not an instance) in ApplicationContext
              *
              * Or use a FactoryBean to retrieve your CustomController
              */
            handlerMap.put(url, getApplicationContext().getBean(beanName));
        }

        /**
          * instantiateClass needs no-arg constructor
          */
        Object handler = BeanUtils.instantiateClass(handlerMap.get(url));

        return new HandlerExecutionChain(handler);
    }

    private String extractUrl(HttpServletRequest request) {
        /**
          * Here goes code needed To retrieve URL path from request
          *
          * Take a look at AntPathMatcher, UrlPathHelper and PathMatcher
          *
          * It can be useful To see AbstractUrlHandlerMapping.getHandlerInternal method
          */ 
    }

}

<bean id="br.com.ar.web.servlet.handler.CustomHandlerMapping"/>
<bean id="br.com.ar.web.support.CustomHandlerAdapter"/>
<!--To allow Spring 3.0 controller-->
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>
<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"/>

我希望它能给你一个好的开始

幕后

/**
  * Our HandlerMapping goes here
  */
HandlerMapping handlerMapping = getHandler(request);

HandlerExecutionChain handlerExecutionChain = handlerMapping.getHandler(request);

for(HandlerInterceptor interceptor: handlerExecutionChain.getInterceptors) {
    interceptor.preHandle(request, response, handlerExecutionChain.getHandler());
}

/**
  * Our CustomController goes here
  */
Object handler = handlerExecutionChain.getHandler();

/**
  * Our CustomHandlerAdapter goes here
  */
HandlerAdapter handlerAdapter = getHandlerAdapter(handler);

ModelAndView mav = handlerAdapter.handle(request, response, handler);

for(HandlerInterceptor interceptor: handlerExecutionChain.getInterceptors) {
    interceptor.postHandle(request, response, handlerExecutionChain.getHandler());
}

skaffman 16 年前

您可以以相当大的灵活性将XML和注释样式映射结合起来。两者都可以使用Ant风格的通配符匹配,所以您可以这样做(没有经过测试,但给出了一般的想法):

<bean class="SimpleUrlHandlerMapping">
   <property name="mappings">
      <map>
         <entry key="myController/**" value-ref="myController"/>
      </map>
   </property>
</bean>

<bean id="myController" class="MyController"/>

然后

@Controller
class MyController {
    @RequestMapping("**/someMethod")
    String someMethod(...) {
    }
}

URL /myController/someMethod

你可能需要玩一点让它工作,但这是它的要点。

Arthur Ronald 16 年前

绑定到操作的URL应完全指定 在java文件中

所以依靠 ControllerClassNameHandlerMapping

<bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping"/>

记住ControllerNameHandlerMapping 控制器后缀 如果存在的话 如果只希望第一个字母的大小写较低,请将区分大小写的属性设置为true

package br.com.ar.view.resources;

@Controller
public class UserController {

    /**
      * mapped To /user/form
      */
    @RequestMapping(method=RequesMethod.GET)
    public void form(Model model) {
        model.add(categoryRepository().getCategoryList());
    }

    /**
      * mapped To user/form
      */
    @RequestMapping(method=RequesMethod.POST)
    public void form(User user) {
        userRepository.add(user);
    }

}

还有更多: 如果您使用模块化的应用程序,则可以依赖basePackage属性

br.com.ar.view.financial.AccountController;
br.com.ar.view.resources.ManagementController;

定义基本包

<bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping">
    <property name="basePackage" value="br.com.ar.view"/>
</bean>

你可以打电话给你的账户管理员

/financial/account/form

你可以打电话给你的管理员形式方法as

/resources/management/form

因为我很确定您在配置上使用默认TranslateToViewName约定,所以您的目录结构应该如下所示

/WEB-INF
    /view
        /financial
            /user
                form.jsp

        /resources
            /management
                form.jsp

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/view/"/>
    <property name="suffix" value=".jsp"/>
</bean>

最后,如果你的要求 . 没问题,请定义defaultHandler属性

<bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping">
    <property name="basePackage" value="br.com.ar.view"/>
    <property name="caseSensitive" value="true"/>
    <property name="defaultHandler">
        <bean class="org.springframework.web.servlet.mvc.UrlFilenameViewController"/>
    </property>
</bean>

现在,如果您调用/index.htm(我假设您的DispatcherServlet截获了htm扩展),并且您没有任何IndexController,Spring将查找

/WEB-INF/view/index.jsp