com.techtrip.dynbl.context.config.WebAppinitializer.java Source code

Introduction

Here is the source code for com.techtrip.dynbl.context.config.WebAppinitializer.java

Source

/*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
* 
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* 
* See <http://www.gnu.org/licenses/>.
*/
package com.techtrip.dynbl.context.config;

import java.util.EnumSet;
import java.util.Set;

import javax.servlet.DispatcherType;
import javax.servlet.FilterRegistration;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;

import org.springframework.core.SpringVersion;
import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.ContextLoaderListener;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.filter.CharacterEncodingFilter;
import org.springframework.web.servlet.DispatcherServlet;
import org.springframework.web.util.Log4jConfigListener;

/**
 * The Class WebAppinitializer.
 */
public class WebAppinitializer implements WebApplicationInitializer {

    private static final String ROOT_CONTEXT = "/";
    private static final String APP_SERVLET = "appServlet";
    private static final String APP_CONFIG_LOCATION = "com.techtrip.dynbl.context.config";

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {

        // Setup Context to Accept Annotated Classes on Input (including plain Spring {@code @Component}
        // Stereotypes in addition to JSR-330 Compliant Classes using {@code javax.inject}
        AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();

        //context.setConfigLocation(APP_CONFIG_LOCATION);
        context.setConfigLocation(APP_CONFIG_LOCATION);

        /* 
        * Add a Spring Security Filter using the JEE6 Filter Registration Filter Method from {@code FilterRegistration) that allows filters to be registered
        *  and configured with the specified context
        */
        /*              
        FilterRegistration.Dynamic securityFilter = servletContext.addFilter(ProjectKeyValConsts.SECURITY_FILTER.getKey(), new DelegatingFilterProxy(ProjectKeyValConsts.SECURITY_FILTER.getValue()));
        securityFilter.addMappingForUrlPatterns(EnumSet.allOf(DispatcherType.class), true, ProjectConsts.BASE_URL_MAPPING_PATTERN.getValue()); // where the filter will be applied
        */
        // Add a Character Encoding Filter that specifies an encoding for mapped requests
        FilterRegistration.Dynamic characterEncodingFilter = servletContext.addFilter("characterEncodingFilter",
                new CharacterEncodingFilter());
        characterEncodingFilter.addMappingForUrlPatterns(EnumSet.allOf(DispatcherType.class), true, ROOT_CONTEXT); // where the filter will be applied
        characterEncodingFilter.setInitParameter("encoding", "UTF-8");
        characterEncodingFilter.setInitParameter("forceEncoding", Boolean.TRUE.toString());
        characterEncodingFilter.setAsyncSupported(true);

        servletContext.addListener(new ContextLoaderListener(context));
        servletContext.setInitParameter("defaultHtmlEscape", Boolean.TRUE.toString());

        DispatcherServlet servlet = new DispatcherServlet();

        // no explicit configuration reference here: everything is configured in the root container for simplicity
        servlet.setContextConfigLocation("");

        /* TMT From JEE 6 API Docs:
        * Registers the given servlet instance with this ServletContext under the given servletName.
        * The registered servlet may be further configured via the returned ServletRegistration object. 
        */

        ServletRegistration.Dynamic appServlet = servletContext.addServlet(APP_SERVLET, servlet);
        appServlet.setLoadOnStartup(1);
        appServlet.setAsyncSupported(true);

        Set<String> mappingConflicts = appServlet.addMapping("/");

        if (!mappingConflicts.isEmpty()) {
            throw new IllegalStateException(String.format(
                    "The servlet named '%s' cannot be mapped to '/' under Tomcat versions <= 7.0.14", APP_SERVLET));
        }

        // TMT
        servletContext.addListener(new Log4jConfigListener());

        System.out.println("Application inplemented on Spring Version: " + SpringVersion.getVersion());

    }

}