Spring MVC：与多个Dispatchers一起发现的模糊映射

Question

i'm building a WebApplication with Spring4. The WebApplication Dispatcher is mapped to /app/* because i have a second Spring Dispatcher for REST Services with mapping /services/*

When i try to start the WebApplication Spring throws Exceptions (Ambiguous mapping found) because i have the same mapping ("/persons") in two different Controllers. It is correct, i have this mapping in a Controller in my WebApplication and the same mapping in a RestController. But the Controllers are in different Dispatchers with the different dispatcher mappings. Is there a way to explain Spring that this mappings are correct? Or is it a mistake from myself and the way i go is complete wrong?

Output from Jetty (Stripped some unneeded things):

INFO: Root WebApplicationContext: initialization started
INFO: Mapped "{[/home],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public org.springframework.web.servlet.ModelAndView io.theoperator.controller.Home.showMessage()
INFO: Mapped "{[/home],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public org.springframework.web.servlet.ModelAndView io.theoperator.controller.Home.showMessage()
INFO: Mapped "{[/persons],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public org.springframework.web.servlet.ModelAndView io.theoperator.controller.PersonController.list()
INFO: Mapped "{[/persons],methods=[POST],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public org.springframework.web.servlet.ModelAndView io.theoperator.controller.PersonController.save(io.theoperator.model.Person)
INFO: Root WebApplicationContext: initialization completed in 1319 ms
INFO: FrameworkServlet 'serviceapplication': initialization started
INFO: Mapped "{[/persons/page],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public java.util.Map<java.lang.String, java.lang.Object> io.theoperator.restservice.PersonServiceController.getPage(java.lang.String,java.lang.String,java.lang.String,java.lang.String)
INFO: Mapped "{[/persons],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public io.theoperator.restservice.PersonServiceController$PersonList io.theoperator.restservice.PersonServiceController.getAll()
INFO: Mapped "{[/persons/{id}],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public io.theoperator.model.Person io.theoperator.restservice.PersonServiceController.getPerson(java.lang.String)
Mar 01, 2015 12:36:03 PM org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping registerHandlerMethod
INFO: Mapped "{[/persons/page],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public java.util.Map<java.lang.String, java.lang.Object> io.theoperator.restservice.PersonServiceController.getPage(java.lang.String,java.lang.String,java.lang.String,java.lang.String)
Mar 01, 2015 12:36:03 PM org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping registerHandlerMethod
INFO: Mapped "{[/persons],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public io.theoperator.restservice.PersonServiceController$PersonList io.theoperator.restservice.PersonServiceController.getAll()
Mar 01, 2015 12:36:03 PM org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping registerHandlerMethod
INFO: Mapped "{[/persons/{id}],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public io.theoperator.model.Person io.theoperator.restservice.PersonServiceController.getPerson(java.lang.String)
Mar 01, 2015 12:36:03 PM org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping registerHandlerMethod
INFO: Mapped "{[/home],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public org.springframework.web.servlet.ModelAndView io.theoperator.controller.Home.showMessage()
Mar 01, 2015 12:36:03 PM org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping registerHandlerMethod
INFO: Mapped "{[/persons/{id}],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public org.springframework.web.servlet.ModelAndView io.theoperator.controller.PersonController.details(java.lang.String)
Mar 01, 2015 12:36:03 PM org.springframework.web.context.support.AnnotationConfigWebApplicationContext refresh
WARNING: Exception encountered during context initialization - cancelling refresh attempt
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerMapping' defined in class path resource [org/springframework/web/servlet/config/annotation/DelegatingWebMvcConfiguration.class]: Invocation of init method failed; nested exception is java.lang.IllegalStateException: Ambiguous mapping found. Cannot map 'personController' bean method 
public org.springframework.web.servlet.ModelAndView io.theoperator.controller.PersonController.list()
to {[/persons],methods=[GET],params=[],headers=[],consumes=[],produces=[],custom=[]}: There is already 'personServiceController' bean method
public io.theoperator.restservice.PersonServiceController$PersonList io.theoperator.restservice.PersonServiceController.getAll() mapped.
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1566)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:762)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)
    at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:535)
    at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)
    at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    at javax.servlet.GenericServlet.init(GenericServlet.java:244)
    at org.eclipse.jetty.servlet.ServletHolder.initServlet(ServletHolder.java:613)
    at org.eclipse.jetty.servlet.ServletHolder.initialize(ServletHolder.java:396)
    at org.eclipse.jetty.servlet.ServletHandler.initialize(ServletHandler.java:871)
    at org.eclipse.jetty.servlet.ServletContextHandler.startContext(ServletContextHandler.java:341)
    at org.eclipse.jetty.webapp.WebAppContext.startWebapp(WebAppContext.java:1343)
    at org.eclipse.jetty.maven.plugin.JettyWebAppContext.startWebapp(JettyWebAppContext.java:296)
    at org.eclipse.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1336)
    at org.eclipse.jetty.server.handler.ContextHandler.doStart(ContextHandler.java:742)
    at org.eclipse.jetty.webapp.WebAppContext.doStart(WebAppContext.java:499)
    at org.eclipse.jetty.maven.plugin.JettyWebAppContext.doStart(JettyWebAppContext.java:365)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:132)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:114)
    at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:61)
    at org.eclipse.jetty.server.handler.ContextHandlerCollection.doStart(ContextHandlerCollection.java:163)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:132)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:114)
    at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:61)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.start(ContainerLifeCycle.java:132)
    at org.eclipse.jetty.server.Server.start(Server.java:399)
    at org.eclipse.jetty.util.component.ContainerLifeCycle.doStart(ContainerLifeCycle.java:114)
    at org.eclipse.jetty.server.handler.AbstractHandler.doStart(AbstractHandler.java:61)
    at org.eclipse.jetty.server.Server.doStart(Server.java:366)
    at org.eclipse.jetty.util.component.AbstractLifeCycle.start(AbstractLifeCycle.java:68)
    at org.eclipse.jetty.maven.plugin.AbstractJettyMojo.startJetty(AbstractJettyMojo.java:516)
    at org.eclipse.jetty.maven.plugin.AbstractJettyMojo.execute(AbstractJettyMojo.java:359)
    at org.eclipse.jetty.maven.plugin.JettyRunMojo.execute(JettyRunMojo.java:167)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:132)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:120)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:355)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:155)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:584)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:216)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:160)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:134)

This is my WebApplicationInitializer for the WebApplication:

public class WebApplicationInitializer implements org.springframework.web.WebApplicationInitializer {
@Override
public void onStartup(ServletContext container) {

    AnnotationConfigWebApplicationContext rootContext = new AnnotationConfigWebApplicationContext();
    rootContext.register(WebApplicationConfiguration.class);

    container.addListener(new ContextLoaderListener(rootContext));

    ServletRegistration.Dynamic dispatcher = container.addServlet("webapplication", new DispatcherServlet(rootContext));
    dispatcher.setLoadOnStartup(1);
    dispatcher.addMapping("/app/*");

}
}

and this is my WebApplicationInitializer for REST Services

public class ServiceApplicationInitializer implements org.springframework.web.WebApplicationInitializer {

@Override
public void onStartup(ServletContext container) {

    AnnotationConfigWebApplicationContext rootContext = new AnnotationConfigWebApplicationContext();
    rootContext.register(ServiceApplicationConfiguration.class);

    ServletRegistration.Dynamic dispatcher = container.addServlet("serviceapplication", new DispatcherServlet(rootContext));
    dispatcher.setLoadOnStartup(1);
    dispatcher.addMapping("/services/*");

}
}

Here are the Configurations for the Dispatchers:

@EnableWebMvc
@ComponentScan(basePackages = {
        "io.theoperator.controller",
        "io.theoperator.service",
        "io.theoperator.repository",
        "io.theoperator.configuration",
})
@Configuration
public class WebApplicationConfiguration extends WebMvcConfigurerAdapter {

    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
    }

    @Bean
    public InternalResourceViewResolver getInternalResourceViewResolver() {
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setPrefix("/WEB-INF/pages/");
        resolver.setSuffix(".jsp");
        return resolver;
    }

}

and

@EnableWebMvc
@ComponentScan(basePackages = {
        "io.theoperator.service",
        "io.theoperator.repository",
        "io.theoperator.configuration",
        "io.theoperator.restservice"
})
public class ServiceApplicationConfiguration extends WebMvcConfigurerAdapter {



}

In my WebApplication i have this Controller:

@Controller
@RequestMapping("/persons")
public class PersonController {

    @RequestMapping(method = RequestMethod.GET)
    public ModelAndView list() {
        return new ModelAndView("persons/list");
    }
}

In my ServiceApplication i have a RestController:

@RestController
@RequestMapping("/persons")
public class PersonServiceController {
@RequestMapping(method = RequestMethod.GET)
    public PersonList getAll() {
        return new PersonList(this.personService.list());
    }
}

Edit

I have removed the ContextLoaderListener how magnama suggested. But the error is effectively the same.

Here (Pastebin) is the complete output from Spring. I think something goes very wrong. Spring starts at first the serviceapplication context and registers /home (From HomeController) that is part of the WebApplication. The HomeController is in package io.theoperator.controller which is not part of the ComponentScan of the ServiceApplicationConfiguration... At the moment i have no idea what is wrong...

Answer 1

Thx for all.
I have found my error!
I have created a new project with only seven files: 2 Initializers, 2 Configurations, 2 Controllers and 1 RestController and i have reproduced the same situation.
My error was to put the Initializers and Configurations all in the same package "io.theoperator.configuration".
After splitting to "io.theoperator.configuration.web" and "io.theoperator.configuration.service" and adjusting the ComponentScan in the Configurations the Service Application maps only the RestControllers

I have created a repository on github: Project foo on github.com
The master branch is the working one and branch error with the Ambiguous mapping error.

Special thanks to Magnamag and Pavel for their tip with the double scanning! ;)

regards jomikel

Answer 2

was looking to solve the same problem I had and after reading your post got a solution WITHOUT splitting config files to different folders.

as you explicitly provide config class for each servlet - remove @Configuration annotation in config classes to avoid mess.

Let's assume we have an app, providing WEB and REST services which is working with User database. So REST endpoint would be http://blah-blah-blah/rest and web - http://blah-blah-blah/web . In both cases, when we want to get, ie, list of users - we access, respectively, .../rest/users or .../web/users; for selected user address would be .../rest/users/1 or .../web/users/1, etc. App init class and config classes are in same package, REST and WEB controllers are in rest and web packages, respectively

App init:

public class AppInitializer implements WebApplicationInitializer  {

@Override
public void onStartup(ServletContext container) throws ServletException {
    // Create the 'root' Spring application context
      AnnotationConfigWebApplicationContext rootContext = new AnnotationConfigWebApplicationContext();
      rootContext.register(RootConfig.class);
      //data access layer
      rootContext.register(DataConfig.class);
      // Manage the lifecycle of the root application context
      container.addListener(new ContextLoaderListener(rootContext));

      //--------WEB--------------         

      // Create web dispatcher servlet's application context
      AnnotationConfigWebApplicationContext webDispatcherContext = 
              new AnnotationConfigWebApplicationContext();
      webDispatcherContext.register(WebDispatcherConfig.class);

      // Register and map web dispatcher servlet
      ServletRegistration.Dynamic webDispatcher =
              container.addServlet("webDispatcher", new DispatcherServlet(webDispatcherContext));
      webDispatcher.setLoadOnStartup(1);
      webDispatcher.addMapping("/web/*");

      //--------REST-------------        

      // Create rest dispatcher servlet's application context
      AnnotationConfigWebApplicationContext restDispatcherContext = 
              new AnnotationConfigWebApplicationContext();
      restDispatcherContext.register(RESTDispatcherConfig.class);

      // Register and map rest dispatcher servlet
      ServletRegistration.Dynamic restDispatcher =
              container.addServlet("restDispatcher", new DispatcherServlet(restDispatcherContext));
      restDispatcher.setLoadOnStartup(1);
      restDispatcher.addMapping("/rest/*");

}

web-config:

@EnableWebMvc
@ComponentScan("io.github.d2edev.mywebapp.web")
public class WebDispatcherConfig extends WebMvcConfigurerAdapter {

@Bean
public ViewResolver viewResolver() {
    InternalResourceViewResolver resolver = new InternalResourceViewResolver();
    resolver.setPrefix("/WEB-INF/jsp/");
    resolver.setSuffix(".jsp");
    resolver.setExposeContextBeansAsAttributes(true);
    return resolver;
}



@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
    configurer.enable();
}

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/resources/**").addResourceLocations("/resources/");
}
}

rest-config:

@EnableWebMvc
@ComponentScan("io.github.d2edev.mywebapp.rest")
public class RESTDispatcherConfig {

}

web-controller:

@Controller
@RequestMapping("/users")
public class UserController {

private UserRepository userRepository;

@Autowired
public UserController(UserRepository userRepository) {
    this.userRepository=userRepository;
}

//list all
@RequestMapping(method=RequestMethod.GET)
public String listAllUsers(Model model){
    model.addAttribute("userList", userRepository.findAll());
    return "user/users";
}

//show registration form
@RequestMapping(value="/newUser", method=RequestMethod.GET)
public String showRegistrationForm(){
    return "user/newUser";
}

//other methods here...

}

rest-controller:

@RestController
@RequestMapping("/users")
public class UserControllerREST {

// data source
private UserService userService;

@Autowired
public UserControllerREST(UserService userService) {
    this.userService = userService;
}

// get all
@RequestMapping(method = RequestMethod.GET)
public ResponseEntity<List<User>> getAllUsers() {
    List<User> users = userService.getAll();
    if (users.isEmpty()) {
        return new ResponseEntity<List<User>>(HttpStatus.NO_CONTENT);
    }
    return new ResponseEntity<List<User>>(users, HttpStatus.OK);

}

//other methods to follow...
}

Hope it helps others, at least...