如何动态映射spring-webmvc路径？

Question

这是一个交叉的帖子.我也向spring论坛发布了同样的问题.http://forum.springsource.org/showthread.php?128579-Database-driven-Controller-Mapping

嗨,我正在尝试进行数据库驱动的控制器映射,以便它们可以在运行时更改.

到目前为止,我所拥有的内容如下.

自定义处理程序适配器,以后可以随时进行优化.

@Component
public class DatabasePageUrlHandlerMapping extends AbstractUrlHandlerMapping implements PriorityOrdered {


    @Override
    protected Object getHandlerInternal(HttpServletRequest request)
            throws Exception {
        String lookupPath = getUrlPathHelper().getLookupPathForRequest(request);
        List<Page> pages = Page.findAllPages();
        for (Page page : pages) {
            if (lookupPath.equals(page.getSeoPath())) {
                Object handler = getApplicationContext().getBean("_pageViewController");
                return new HandlerExecutionChain(handler);
            }
        }
        return super.getHandlerInternal(request);
    }

}

我的webmvc-config看起来如下(相关部分)

码:

<context:component-scan base-package="com.artiststogether"
    use-default-filters="false">
    <context:include-filter expression="org.springframework.stereotype.Controller"
        type="annotation" />
</context:component-scan>

<!-- If I don't put an order into this it doesn't fail over to the implementation why? -->
<bean class="com.artiststogether.web.DatabasePageUrlHandlerMapping" p:order="-1" />
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>

这似乎是拿起正确的控制器.但是,当我转到数据库定义的路径(例如"/ a")时,我收到错误

java.lang.NullPointerException
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter$ServletHandlerMethodResolver.useTypeLevelMapping(AnnotationMethodHandlerAdapter.java:675)
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter$ServletHandlerMethodResolver.resolveHandlerMethod(AnnotationMethodHandlerAdapter.java:585)
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:431)
    at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:424)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:900)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:827)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
        ....

我是否需要定义自定义注释处理程序？

说实话,整个过程似乎比应该更难.我希望1个控制器处理对外部定义的url路径的所有请求这是正确的绕过它的方法.

如果可能的话,我还想传入与控制器匹配的对象,而不是在控制器中进行新的查找.这基本上构成了我的视图模型.

有关如何使这项工作的任何建议？

编辑 为了记录,NPE就在这里

    private boolean useTypeLevelMapping(HttpServletRequest request) {
        if (!hasTypeLevelMapping() || ObjectUtils.isEmpty(getTypeLevelMapping().value())) {
            return false;
        }
        return (Boolean) request.getAttribute(HandlerMapping.INTROSPECT_TYPE_LEVEL_MAPPING);
    }

pom.xml中的另一个Edit版本号

<properties>
    <aspectj.version>1.6.12</aspectj.version>
    <java.version>6</java.version>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <roo.version>1.2.1.RELEASE</roo.version>
    <slf4j.version>1.6.4</slf4j.version>
    <spring.version>3.1.0.RELEASE</spring.version>
<spring-security.version>3.1.0.RELEASE</spring-security.version>
</properties>

我自己已经在下面回答了这个问题,但是我仍然对那些正在做正确的方法的人感兴趣.

Answer 1

为了解决这个具体问题，让我暂时推荐一种解决方法 -

创建您自己的 handlerAdapter，内部组成 AnnotationMethodHandlerAdapter：

public DBAnnotationMethodHandlerAdapter implements HandlerAdapter,{
    private AnnotationHandlerAdapter target;

    @Override
    public boolean supports(Object handler) {
        return this.target.supports(handler);
    }

    @Override
    public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        request.setAttribute(HandlerMapping.INTROSPECT_TYPE_LEVEL_MAPPING, true);
        return this.target.handle(request, response, handler);
    }

    public void setTarget(AnnotationHandlerAdapter target){
        this.target = target;
    }

}

   <bean class="mypkg.DBAnnotationMethodHandlerAdapter">
        <property name="target">
            <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"/>
        </property>
    </bean>

这应该可以解决当前问题，但您可能会遇到其他问题