Servlet Config

In a Servlet environment, you have the option of configuring the Servlet container programmatically as an alternative or in combination with a web.xml file. The following example registers a MockDispatcher:

Java

import cn.taketoday.web.WebApplicationInitializer;

public class MyWebApplicationInitializer implements WebApplicationInitializer {

  @Override
  public void onStartup(ServletContext container) {
    XmlWebApplicationContext appContext = new XmlWebApplicationContext();
    appContext.setConfigLocation("/WEB-INF/spring/dispatcher-config.xml");

    ServletRegistration.Dynamic registration = container.addServlet("dispatcher", new DispatcherServlet(appContext));
    registration.setLoadOnStartup(1);
    registration.addMapping("/");
  }
}

WebApplicationInitializer is an interface provided by Web MVC that ensures your implementation is detected and automatically used to initialize any Servlet 3 container. An abstract base class implementation of WebApplicationInitializer named AbstractDispatcherServletInitializer makes it even easier to register the MockDispatcher by overriding methods to specify the mockApi mapping and the location of the MockDispatcher configuration.

This is recommended for applications that use Java-based Infra configuration, as the following example shows:

Java

public class MyWebAppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

  @Override
  protected Class<?>[] getRootConfigClasses() {
    return null;
  }

  @Override
  protected Class<?>[] getServletConfigClasses() {
    return new Class<?>[] { MyWebConfig.class };
  }

  @Override
  protected String[] getServletMappings() {
    return new String[] { "/" };
  }
}

If you use XML-based Infra configuration, you should extend directly from AbstractDispatcherServletInitializer, as the following example shows:

Java

public class MyWebAppInitializer extends AbstractDispatcherServletInitializer {

  @Override
  protected WebApplicationContext createRootApplicationContext() {
    return null;
  }

  @Override
  protected WebApplicationContext createServletApplicationContext() {
    XmlWebApplicationContext cxt = new XmlWebApplicationContext();
    cxt.setConfigLocation("/WEB-INF/spring/dispatcher-config.xml");
    return cxt;
  }

  @Override
  protected String[] getServletMappings() {
    return new String[] { "/" };
  }
}

AbstractDispatcherServletInitializer also provides a convenient way to add Filter instances and have them be automatically mapped to the MockDispatcher, as the following example shows:

Java

public class MyWebAppInitializer extends AbstractDispatcherServletInitializer {

  // ...

  @Override
  protected Filter[] getServletFilters() {
    return new Filter[] {
      new HiddenHttpMethodFilter(), new CharacterEncodingFilter() };
  }
}

Each filter is added with a default name based on its concrete type and automatically mapped to the MockDispatcher.

The isAsyncSupported protected method of AbstractDispatcherServletInitializer provides a single place to enable async support on the MockDispatcher and all filters mapped to it. By default, this flag is set to true.

Finally, if you need to further customize the MockDispatcher itself, you can override the createDispatcherServlet method.