[FIXED] Spring MVC configuration breaks Tomcat's trailing slash mapping

Issue

Under Tomcat 9 src/main/webapp folder, I created a sub-folder named app containing an index.jsp file. If I request localhost:8080/app I get a 404 error, while with a trailing slash localhost:8080/app/ it works fine.
If I disable spring mvc the problem disappears. Tomcat logs with Spring MVC enabled:
With trailing slash

21:17:33.351 [http-nio-8080-exec-7] DEBUG o.s.web.servlet.DispatcherServlet.traceDebug(91) - GET "/app/", parameters={}
21:17:33.351 [http-nio-8080-exec-7] DEBUG o.s.w.s.h.SimpleUrlHandlerMapping.getHandler(414) - Mapped to ResourceHttpRequestHandler ["/"]
21:17:33.352 [http-nio-8080-exec-7] DEBUG o.s.web.servlet.DispatcherServlet.logResult(1131) - Completed 304 NOT_MODIFIED

Without traling slash:

21:17:57.046 [http-nio-8080-exec-9] DEBUG o.s.web.servlet.DispatcherServlet.traceDebug(91) - GET "/app", parameters={}
21:17:57.047 [http-nio-8080-exec-9] DEBUG o.s.w.s.h.SimpleUrlHandlerMapping.getHandler(414) - Mapped to ResourceHttpRequestHandler ["/"]
21:17:57.048 [http-nio-8080-exec-9] DEBUG o.s.w.s.r.ResourceHttpRequestHandler.handleRequest(487) - Resource not found
21:17:57.048 [http-nio-8080-exec-9] DEBUG o.s.web.servlet.DispatcherServlet.logResult(1131) - Completed 404 NOT_FOUND

My web.xml dispatcher servlet section:

<servlet>
    <servlet-name>dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>dispatcher</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

My webapp context:

<mvc:resources location="/" mapping="/**"></mvc:resources>
<mvc:annotation-driven>
        <mvc:path-matching trailing-slash="true" />
</mvc:annotation-driven>
<context:component-scan base-package="com.example.controller" />
    
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass"
            value="org.springframework.web.servlet.view.JstlView" />
        <property name="prefix" value="/WEB-INF/spring/views/" />
        <property name="suffix" value=".jsp" />
    </bean>

How can I configure Spring MVC to automatically add '/' in a path request (E.g. /app)?

Solution

Letting Tomcat serve static resources solves my problem. I removed Spring's static resources handler:

<mvc:resources location="/" mapping="/**"></mvc:resources>

and added the default servlet handler in order to let Tomcat handle requests of static files:

<mvc:default-servlet-handler/>

Answered By - lainatnavi