Java tutorial
/* * Copyright 2004, 2005, 2006 Acegi Technology Pty Limited * * 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 * * https://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.springframework.security.web.savedrequest; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Arrays; import java.util.Enumeration; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Set; import java.util.TimeZone; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * Provides request parameters, headers and cookies from either an original request or a * saved request. * * <p> * Note that not all request parameters in the original request are emulated by this * wrapper. Nevertheless, the important data from the original request is emulated and * this should prove adequate for most purposes (in particular standard HTTP GET and POST * operations). * * <p> * Added into a request by * {@link org.springframework.security.web.savedrequest.RequestCacheAwareFilter}. * * @author Andrey Grebnev * @author Ben Alex * @author Luke Taylor */ class SavedRequestAwareWrapper extends HttpServletRequestWrapper { // ~ Static fields/initializers // ===================================================================================== protected static final Log logger = LogFactory.getLog(SavedRequestAwareWrapper.class); protected static final TimeZone GMT_ZONE = TimeZone.getTimeZone("GMT"); /** The default Locale if none are specified. */ protected static Locale defaultLocale = Locale.getDefault(); // ~ Instance fields // ================================================================================================ protected SavedRequest savedRequest = null; /** * The set of SimpleDateFormat formats to use in getDateHeader(). Notice that because * SimpleDateFormat is not thread-safe, we can't declare formats[] as a static * variable. */ protected final SimpleDateFormat[] formats = new SimpleDateFormat[3]; // ~ Constructors // =================================================================================================== public SavedRequestAwareWrapper(SavedRequest saved, HttpServletRequest request) { super(request); savedRequest = saved; formats[0] = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss zzz", Locale.US); formats[1] = new SimpleDateFormat("EEEEEE, dd-MMM-yy HH:mm:ss zzz", Locale.US); formats[2] = new SimpleDateFormat("EEE MMMM d HH:mm:ss yyyy", Locale.US); formats[0].setTimeZone(GMT_ZONE); formats[1].setTimeZone(GMT_ZONE); formats[2].setTimeZone(GMT_ZONE); } // ~ Methods // ======================================================================================================== @Override public long getDateHeader(String name) { String value = getHeader(name); if (value == null) { return -1L; } // Attempt to convert the date header in a variety of formats long result = FastHttpDateFormat.parseDate(value, formats); if (result != -1L) { return result; } throw new IllegalArgumentException(value); } @Override public String getHeader(String name) { List<String> values = savedRequest.getHeaderValues(name); return values.isEmpty() ? null : values.get(0); } @Override @SuppressWarnings("unchecked") public Enumeration getHeaderNames() { return new Enumerator<>(savedRequest.getHeaderNames()); } @Override @SuppressWarnings("unchecked") public Enumeration getHeaders(String name) { return new Enumerator<>(savedRequest.getHeaderValues(name)); } @Override public int getIntHeader(String name) { String value = getHeader(name); if (value == null) { return -1; } else { return Integer.parseInt(value); } } @Override public Locale getLocale() { List<Locale> locales = savedRequest.getLocales(); return locales.isEmpty() ? Locale.getDefault() : locales.get(0); } @Override @SuppressWarnings("unchecked") public Enumeration getLocales() { List<Locale> locales = savedRequest.getLocales(); if (locales.isEmpty()) { // Fall back to default locale locales = new ArrayList<>(1); locales.add(Locale.getDefault()); } return new Enumerator<>(locales); } @Override public String getMethod() { return savedRequest.getMethod(); } /** * If the parameter is available from the wrapped request then the request has been * forwarded/included to a URL with parameters, either supplementing or overriding the * saved request values. * <p> * In this case, the value from the wrapped request should be used. * <p> * If the value from the wrapped request is null, an attempt will be made to retrieve * the parameter from the saved request. */ @Override public String getParameter(String name) { String value = super.getParameter(name); if (value != null) { return value; } String[] values = savedRequest.getParameterValues(name); if (values == null || values.length == 0) { return null; } return values[0]; } @Override @SuppressWarnings("unchecked") public Map getParameterMap() { Set<String> names = getCombinedParameterNames(); Map<String, String[]> parameterMap = new HashMap<>(names.size()); for (String name : names) { parameterMap.put(name, getParameterValues(name)); } return parameterMap; } @SuppressWarnings("unchecked") private Set<String> getCombinedParameterNames() { Set<String> names = new HashSet<>(); names.addAll(super.getParameterMap().keySet()); names.addAll(savedRequest.getParameterMap().keySet()); return names; } @Override @SuppressWarnings("unchecked") public Enumeration getParameterNames() { return new Enumerator(getCombinedParameterNames()); } @Override public String[] getParameterValues(String name) { String[] savedRequestParams = savedRequest.getParameterValues(name); String[] wrappedRequestParams = super.getParameterValues(name); if (savedRequestParams == null) { return wrappedRequestParams; } if (wrappedRequestParams == null) { return savedRequestParams; } // We have parameters in both saved and wrapped requests so have to merge them List<String> wrappedParamsList = Arrays.asList(wrappedRequestParams); List<String> combinedParams = new ArrayList<>(wrappedParamsList); // We want to add all parameters of the saved request *apart from* duplicates of // those already added for (String savedRequestParam : savedRequestParams) { if (!wrappedParamsList.contains(savedRequestParam)) { combinedParams.add(savedRequestParam); } } return combinedParams.toArray(new String[combinedParams.size()]); } }