Java tutorial
/* * Copyright (C) 2007-2013 Crafter Software Corporation. * * 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. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.craftercms.security.authorization.impl; import java.io.IOException; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang.StringUtils; import org.craftercms.security.api.RequestContext; import org.craftercms.security.api.SecurityConstants; import org.craftercms.security.authentication.BaseHandler; import org.craftercms.security.authorization.AccessDeniedHandler; import org.craftercms.security.exception.AccessDeniedException; import org.craftercms.security.exception.CrafterSecurityException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Default implementation of {@link AccessDeniedHandler}: forwards to the error page URL, * so that the original URL is preserved in * the browser. If not error URL is specified, a 403 FORBIDDEN error is sent. * * @author Alfonso Vsquez */ public class AccessDeniedHandlerImpl extends BaseHandler implements AccessDeniedHandler { private static final Logger logger = LoggerFactory.getLogger(AccessDeniedHandlerImpl.class); protected String errorPageUrl; public AccessDeniedHandlerImpl() { super(); } /** * Sets the error page URL to forward to. */ public void setErrorPageUrl(String errorPageUrl) { this.errorPageUrl = errorPageUrl; } /** * Saves the access denied in the request, so it can be used after the request is forwarded. It then forwards to * the error page, * but if not error page was specified, a 403 error is sent. * * @param e the exception with the reason of the access deny * @param context the request context * @throws CrafterSecurityException * @throws IOException */ public void onAccessDenied(AccessDeniedException e, RequestContext context) throws CrafterSecurityException, IOException { saveException(e, context); if (isRedirectRequired && StringUtils.isNotEmpty(errorPageUrl)) { forwardToErrorPage(context); } else { sendError(e, context); } } /** * Saves the exception in the request. */ protected void saveException(AccessDeniedException e, RequestContext context) { if (logger.isDebugEnabled()) { logger.debug("Saving access denied exception in request to use after forward"); } context.getRequest().setAttribute(SecurityConstants.ACCESS_DENIED_EXCEPTION_ATTRIBUTE, e); } /** * Forwards the request to the error page (to preserve the browser URL). */ protected void forwardToErrorPage(RequestContext context) throws CrafterSecurityException, IOException { HttpServletRequest request = context.getRequest(); HttpServletResponse response = context.getResponse(); response.setStatus(HttpServletResponse.SC_FORBIDDEN); if (logger.isDebugEnabled()) { logger.debug("Forwarding to error page at " + errorPageUrl + ", with 403 FORBIDDEN status"); } RequestDispatcher dispatcher = request.getRequestDispatcher(errorPageUrl); try { dispatcher.forward(request, response); } catch (ServletException e) { throw new CrafterSecurityException(e.getMessage(), e); } } /** * Sends a 403 FORBIDDEN error. */ protected void sendError(AccessDeniedException e, RequestContext requestContext) throws IOException { if (logger.isDebugEnabled()) { logger.debug("Sending 403 FORBIDDEN error"); } requestContext.getResponse().setContentType("application/json"); requestContext.getResponse().sendError(HttpServletResponse.SC_FORBIDDEN, e.getMessage()); } public boolean isRedirectRequired() { return isRedirectRequired; } public void setRedirectRequired(boolean isRedirectRequired) { this.isRedirectRequired = isRedirectRequired; } }