Example usage for javax.servlet ServletContext createServlet

List of usage examples for javax.servlet ServletContext createServlet

Introduction

In this page you can find the example usage for javax.servlet ServletContext createServlet.

Prototype

public <T extends Servlet> T createServlet(Class<T> clazz) throws ServletException;

Source Link

Document

Instantiates the given Servlet class.

Usage

From source file:com.jsmartframework.web.manager.ContextControl.java

@Override
@SuppressWarnings("unchecked")
public void contextInitialized(ServletContextEvent event) {
    try {//from   w ww.ja  v  a  2  s  . c  o  m
        ServletContext servletContext = event.getServletContext();

        CONFIG.init(servletContext);
        if (CONFIG.getContent() == null) {
            throw new RuntimeException("Configuration file " + Constants.WEB_CONFIG_XML
                    + " was not found in WEB-INF resources folder!");
        }

        String contextConfigLocation = "com.jsmartframework.web.manager";
        if (CONFIG.getContent().getPackageScan() != null) {
            contextConfigLocation += "," + CONFIG.getContent().getPackageScan();
        }

        // Configure necessary parameters in the ServletContext to set Spring configuration without needing an XML file
        AnnotationConfigWebApplicationContext configWebAppContext = new AnnotationConfigWebApplicationContext();
        configWebAppContext.setConfigLocation(contextConfigLocation);

        CONTEXT_LOADER = new ContextLoader(configWebAppContext);
        CONTEXT_LOADER.initWebApplicationContext(servletContext);

        TagEncrypter.init();
        TEXTS.init();
        IMAGES.init(servletContext);
        HANDLER.init(servletContext);

        // ServletControl -> @MultipartConfig @WebServlet(name = "ServletControl", displayName = "ServletControl", loadOnStartup = 1)
        Servlet servletControl = servletContext.createServlet(
                (Class<? extends Servlet>) Class.forName("com.jsmartframework.web.manager.ServletControl"));
        ServletRegistration.Dynamic servletControlReg = (ServletRegistration.Dynamic) servletContext
                .addServlet("ServletControl", servletControl);
        servletControlReg.setAsyncSupported(true);
        servletControlReg.setLoadOnStartup(1);

        // ServletControl Initial Parameters
        InitParam[] initParams = CONFIG.getContent().getInitParams();
        if (initParams != null) {
            for (InitParam initParam : initParams) {
                servletControlReg.setInitParameter(initParam.getName(), initParam.getValue());
            }
        }

        // MultiPart to allow file upload on ServletControl
        MultipartConfigElement multipartElement = getServletMultipartElement();
        if (multipartElement != null) {
            servletControlReg.setMultipartConfig(multipartElement);
        }

        // Security constraint to ServletControl
        ServletSecurityElement servletSecurityElement = getServletSecurityElement(servletContext);
        if (servletSecurityElement != null) {
            servletControlReg.setServletSecurity(servletSecurityElement);
        }

        // TODO: Fix problem related to authentication by container to use SSL dynamically (Maybe create more than one servlet for secure and non-secure patterns)
        // Check also the use of request.login(user, pswd)
        // Check the HttpServletRequest.BASIC_AUTH, CLIENT_CERT_AUTH, FORM_AUTH, DIGEST_AUTH
        // servletReg.setRunAsRole("admin");
        // servletContext.declareRoles("admin");

        // ServletControl URL mapping
        String[] servletMapping = getServletMapping();
        servletControlReg.addMapping(servletMapping);

        // ErrorFilter -> @WebFilter(urlPatterns = {"/*"})
        Filter errorFilter = servletContext.createFilter(
                (Class<? extends Filter>) Class.forName("com.jsmartframework.web.filter.ErrorFilter"));
        FilterRegistration.Dynamic errorFilterReg = (FilterRegistration.Dynamic) servletContext
                .addFilter("ErrorFilter", errorFilter);

        errorFilterReg.setAsyncSupported(true);
        errorFilterReg.addMappingForUrlPatterns(
                EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD, DispatcherType.ERROR), true, "/*");

        // EncodeFilter -> @WebFilter(urlPatterns = {"/*"})
        Filter encodeFilter = servletContext.createFilter(
                (Class<? extends Filter>) Class.forName("com.jsmartframework.web.filter.EncodeFilter"));
        FilterRegistration.Dynamic encodeFilterReg = (FilterRegistration.Dynamic) servletContext
                .addFilter("EncodeFilter", encodeFilter);

        encodeFilterReg.setAsyncSupported(true);
        encodeFilterReg.addMappingForUrlPatterns(EnumSet.of(DispatcherType.REQUEST, DispatcherType.ERROR), true,
                "/*");

        // CacheFilter -> @WebFilter(urlPatterns = {"/*"})
        Filter cacheFilter = servletContext.createFilter(
                (Class<? extends Filter>) Class.forName("com.jsmartframework.web.filter.CacheFilter"));
        FilterRegistration.Dynamic cacheFilterReg = (FilterRegistration.Dynamic) servletContext
                .addFilter("CacheFilter", cacheFilter);

        cacheFilterReg.setAsyncSupported(true);
        cacheFilterReg.addMappingForUrlPatterns(EnumSet.of(DispatcherType.REQUEST, DispatcherType.ERROR), true,
                "/*");

        // Add custom filters defined by client
        for (String filterName : sortCustomFilters()) {
            Filter customFilter = servletContext
                    .createFilter((Class<? extends Filter>) HANDLER.webFilters.get(filterName));
            HANDLER.executeInjection(customFilter);

            WebFilter webFilter = customFilter.getClass().getAnnotation(WebFilter.class);
            FilterRegistration.Dynamic customFilterReg = (FilterRegistration.Dynamic) servletContext
                    .addFilter(filterName, customFilter);

            if (webFilter.initParams() != null) {
                for (WebInitParam initParam : webFilter.initParams()) {
                    customFilterReg.setInitParameter(initParam.name(), initParam.value());
                }
            }
            customFilterReg.setAsyncSupported(webFilter.asyncSupported());
            customFilterReg.addMappingForUrlPatterns(EnumSet.copyOf(Arrays.asList(webFilter.dispatcherTypes())),
                    true, webFilter.urlPatterns());
        }

        // FilterControl -> @WebFilter(servletNames = {"ServletControl"})
        Filter filterControl = servletContext.createFilter(
                (Class<? extends Filter>) Class.forName("com.jsmartframework.web.manager.FilterControl"));
        FilterRegistration.Dynamic filterControlReg = (FilterRegistration.Dynamic) servletContext
                .addFilter("FilterControl", filterControl);

        filterControlReg.setAsyncSupported(true);
        filterControlReg.addMappingForServletNames(EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD,
                DispatcherType.ERROR, DispatcherType.INCLUDE), true, "ServletControl");

        // OutputFilter -> @WebFilter(servletNames = {"ServletControl"})
        Filter outputFilter = servletContext.createFilter(
                (Class<? extends Filter>) Class.forName("com.jsmartframework.web.manager.OutputFilter"));
        FilterRegistration.Dynamic outputFilterReg = (FilterRegistration.Dynamic) servletContext
                .addFilter("OutputFilter", outputFilter);

        outputFilterReg.setAsyncSupported(true);
        outputFilterReg.addMappingForServletNames(EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD,
                DispatcherType.ERROR, DispatcherType.INCLUDE), true, "ServletControl");

        // AsyncFilter -> @WebFilter(servletNames = {"ServletControl"})
        // Filter used case AsyncContext is dispatched internally by AsyncBean implementation
        Filter asyncFilter = servletContext.createFilter(
                (Class<? extends Filter>) Class.forName("com.jsmartframework.web.manager.AsyncFilter"));
        FilterRegistration.Dynamic asyncFilterReg = (FilterRegistration.Dynamic) servletContext
                .addFilter("AsyncFilter", asyncFilter);

        asyncFilterReg.setAsyncSupported(true);
        asyncFilterReg.addMappingForServletNames(EnumSet.of(DispatcherType.ASYNC), true, "ServletControl");

        // SessionControl -> @WebListener
        EventListener sessionListener = servletContext.createListener((Class<? extends EventListener>) Class
                .forName("com.jsmartframework.web.manager.SessionControl"));
        servletContext.addListener(sessionListener);

        // RequestControl -> @WebListener
        EventListener requestListener = servletContext.createListener((Class<? extends EventListener>) Class
                .forName("com.jsmartframework.web.manager.RequestControl"));
        servletContext.addListener(requestListener);

        // Custom WebServlet -> Custom Servlets created by application
        for (String servletName : HANDLER.webServlets.keySet()) {
            Servlet customServlet = servletContext
                    .createServlet((Class<? extends Servlet>) HANDLER.webServlets.get(servletName));
            HANDLER.executeInjection(customServlet);

            WebServlet webServlet = customServlet.getClass().getAnnotation(WebServlet.class);
            ServletRegistration.Dynamic customReg = (ServletRegistration.Dynamic) servletContext
                    .addServlet(servletName, customServlet);

            customReg.setLoadOnStartup(webServlet.loadOnStartup());
            customReg.setAsyncSupported(webServlet.asyncSupported());

            WebInitParam[] customInitParams = webServlet.initParams();
            if (customInitParams != null) {
                for (WebInitParam customInitParam : customInitParams) {
                    customReg.setInitParameter(customInitParam.name(), customInitParam.value());
                }
            }

            // Add mapping url for custom servlet
            customReg.addMapping(webServlet.urlPatterns());

            if (customServlet.getClass().isAnnotationPresent(MultipartConfig.class)) {
                customReg.setMultipartConfig(new MultipartConfigElement(
                        customServlet.getClass().getAnnotation(MultipartConfig.class)));
            }
        }

        // Controller Dispatcher for Spring MVC
        Set<String> requestPaths = HANDLER.requestPaths.keySet();
        if (!requestPaths.isEmpty()) {
            ServletRegistration.Dynamic mvcDispatcherReg = servletContext.addServlet("DispatcherServlet",
                    new DispatcherServlet(configWebAppContext));
            mvcDispatcherReg.setLoadOnStartup(1);
            mvcDispatcherReg.addMapping(requestPaths.toArray(new String[requestPaths.size()]));

            // RequestPathFilter -> @WebFilter(servletNames = {"DispatcherServlet"})
            Filter requestPathFilter = servletContext.createFilter((Class<? extends Filter>) Class
                    .forName("com.jsmartframework.web.manager.RequestPathFilter"));
            FilterRegistration.Dynamic reqPathFilterReg = (FilterRegistration.Dynamic) servletContext
                    .addFilter("RequestPathFilter", requestPathFilter);

            reqPathFilterReg.addMappingForServletNames(EnumSet.of(DispatcherType.REQUEST,
                    DispatcherType.FORWARD, DispatcherType.ERROR, DispatcherType.INCLUDE, DispatcherType.ASYNC),
                    true, "DispatcherServlet");
        }
    } catch (Exception ex) {
        throw new RuntimeException(ex);
    }
}