Java tutorial
/* * Copyright 2004-2005 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.grails.web.servlet; import grails.core.GrailsApplication; import grails.core.GrailsControllerClass; import grails.plugins.GrailsPluginManager; import grails.util.Holders; import grails.web.mvc.FlashScope; import grails.web.pages.GroovyPagesUriService; import groovy.lang.GroovyObject; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.codehaus.groovy.grails.web.metaclass.ControllerDynamicMethods; import org.grails.gsp.ResourceAwareTemplateEngine; import org.grails.web.pages.DefaultGroovyPagesUriService; import org.grails.web.util.GrailsApplicationAttributes; import org.springframework.beans.BeansException; import org.springframework.context.ApplicationContext; import org.springframework.context.MessageSource; import org.springframework.util.Assert; import org.springframework.validation.Errors; import org.springframework.web.util.UrlPathHelper; import javax.servlet.ServletContext; import javax.servlet.ServletRequest; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import java.io.Writer; /** * Holds knowledge about how to obtain certain attributes from either the ServletContext * or the HttpServletRequest instance. * * @see org.grails.web.servlet.mvc.GrailsWebRequest * * @author Graeme Rocher * @since 0.3 */ public class DefaultGrailsApplicationAttributes implements GrailsApplicationAttributes, org.codehaus.groovy.grails.web.servlet.GrailsApplicationAttributes { protected static final String DEFAULT_NAMESPACE = "g"; private static Log LOG = LogFactory.getLog(DefaultGrailsApplicationAttributes.class); private UrlPathHelper urlHelper = new UrlPathHelper(); private ServletContext context; private ApplicationContext appContext; // Beans used very often private ResourceAwareTemplateEngine pagesTemplateEngine; private GrailsApplication grailsApplication; private GroovyPagesUriService groovyPagesUriService; private MessageSource messageSource; private GrailsPluginManager pluginManager; public DefaultGrailsApplicationAttributes(ServletContext context) { this.context = context; if (context != null) { appContext = (ApplicationContext) context.getAttribute(APPLICATION_CONTEXT); if (appContext == null) { appContext = Holders.findApplicationContext(); } } } public ApplicationContext getApplicationContext() { return appContext; } private GrailsPluginManager getPluginManager() { if (pluginManager == null) { pluginManager = fetchBeanFromAppCtx(GrailsPluginManager.BEAN_NAME); } return pluginManager; } @SuppressWarnings("unchecked") private <T> T fetchBeanFromAppCtx(String name) { if (appContext == null) { return null; } try { if (appContext.containsBean(name)) { return (T) appContext.getBean(name); } else { return null; } } catch (BeansException e) { LOG.warn("Bean named '" + name + "' is missing."); return null; } } public String getPluginContextPath(HttpServletRequest request) { GroovyObject controller = getController(request); if (controller != null && getPluginManager() != null) { String path = getPluginManager().getPluginPathForInstance(controller); return path == null ? "" : path; } return ""; } public GroovyObject getController(ServletRequest request) { return (GroovyObject) request.getAttribute(CONTROLLER); } public String getControllerUri(ServletRequest request) { return "/" + getControllerName(request); } private String getControllerName(ServletRequest request) { String controllerName = (String) request .getAttribute(GrailsApplicationAttributes.CONTROLLER_NAME_ATTRIBUTE); if (controllerName == null || controllerName.length() == 0) { GroovyObject controller = getController(request); if (controller != null) { controllerName = (String) controller.getProperty(ControllerDynamicMethods.CONTROLLER_NAME_PROPERTY); request.setAttribute(GrailsApplicationAttributes.CONTROLLER_NAME_ATTRIBUTE, controllerName); if (controller instanceof GrailsControllerClass) { String namespace = ((GrailsControllerClass) controller).getNamespace(); if (namespace != null) { request.setAttribute(GrailsApplicationAttributes.CONTROLLER_NAMESPACE_ATTRIBUTE, namespace); } } } } return controllerName != null ? controllerName : ""; } /** * @deprecated Use {@link org.grails.web.servlet.mvc.GrailsWebRequest#getContextPath() instead} * @param request The Servlet Reqest * @return The Application URI */ @Deprecated public String getApplicationUri(ServletRequest request) { String appUri = (String) request.getAttribute(GrailsApplicationAttributes.APP_URI_ATTRIBUTE); if (appUri == null) { appUri = urlHelper.getContextPath((HttpServletRequest) request); } return appUri; } public ServletContext getServletContext() { return context; } public FlashScope getFlashScope(ServletRequest request) { if (!(request instanceof HttpServletRequest)) { return null; } HttpServletRequest servletRequest = (HttpServletRequest) request; HttpSession session = servletRequest.getSession(false); FlashScope fs; if (session != null) { fs = (FlashScope) session.getAttribute(FLASH_SCOPE); } else { fs = (FlashScope) request.getAttribute(FLASH_SCOPE); } if (fs == null) { fs = new GrailsFlashScope(); if (session != null) { session.setAttribute(FLASH_SCOPE, fs); } else { request.setAttribute(FLASH_SCOPE, fs); } } return fs; } public String getTemplateUri(CharSequence templateName, ServletRequest request) { Assert.notNull(templateName, "Argument [template] cannot be null"); return getGroovyPagesUriService().getTemplateURI(getControllerName(request), templateName.toString()); } public String getViewUri(String viewName, HttpServletRequest request) { Assert.notNull(viewName, "Argument [view] cannot be null"); return getGroovyPagesUriService().getDeployedViewURI(getControllerName(request), viewName); } public String getControllerActionUri(ServletRequest request) { GroovyObject controller = getController(request); return (String) controller.getProperty(ControllerDynamicMethods.ACTION_URI_PROPERTY); } public Errors getErrors(ServletRequest request) { return (Errors) request.getAttribute(ERRORS); } public ResourceAwareTemplateEngine getPagesTemplateEngine() { if (pagesTemplateEngine == null) { pagesTemplateEngine = fetchBeanFromAppCtx(ResourceAwareTemplateEngine.BEAN_ID); } if (pagesTemplateEngine == null && LOG.isWarnEnabled()) { LOG.warn("No bean named [" + ResourceAwareTemplateEngine.BEAN_ID + "] defined in Spring application context!"); } return pagesTemplateEngine; } public GrailsApplication getGrailsApplication() { if (grailsApplication == null) { grailsApplication = fetchBeanFromAppCtx(GrailsApplication.APPLICATION_ID); if (grailsApplication == null) { grailsApplication = Holders.findApplication(); } } return grailsApplication; } public Writer getOut(HttpServletRequest request) { return (Writer) request.getAttribute(OUT); } public void setOut(HttpServletRequest request, Writer out2) { request.setAttribute(OUT, out2); } public String getNoSuffixViewURI(GroovyObject controller, String viewName) { return getGroovyPagesUriService().getNoSuffixViewURI(controller, viewName); } public String getTemplateURI(GroovyObject controller, String templateName) { return getGroovyPagesUriService().getTemplateURI(controller, templateName); } @Override public String getTemplateURI(GroovyObject controller, String templateName, boolean includeExtension) { return getGroovyPagesUriService().getTemplateURI(controller, templateName, includeExtension); } public GroovyPagesUriService getGroovyPagesUriService() { if (groovyPagesUriService == null) { groovyPagesUriService = fetchBeanFromAppCtx(GroovyPagesUriService.BEAN_ID); if (groovyPagesUriService == null) { groovyPagesUriService = new DefaultGroovyPagesUriService(); } } return groovyPagesUriService; } public MessageSource getMessageSource() { if (messageSource == null) { messageSource = fetchBeanFromAppCtx("messageSource"); } return messageSource; } }