001/*
002 * Copyright 2002-2017 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.web.servlet.theme;
018
019import javax.servlet.http.HttpServletRequest;
020import javax.servlet.http.HttpServletResponse;
021
022import org.springframework.lang.Nullable;
023
024/**
025 * {@link org.springframework.web.servlet.ThemeResolver} implementation
026 * that simply uses a fixed theme. The fixed name can be defined via
027 * the "defaultThemeName" property; out of the box, it is "theme".
028 *
029 * <p>Note: Does not support {@code setThemeName}, as the fixed theme
030 * cannot be changed.
031 *
032 * @author Jean-Pierre Pawlak
033 * @author Juergen Hoeller
034 * @since 17.06.2003
035 * @see #setDefaultThemeName
036 */
037public class FixedThemeResolver extends AbstractThemeResolver {
038
039        @Override
040        public String resolveThemeName(HttpServletRequest request) {
041                return getDefaultThemeName();
042        }
043
044        @Override
045        public void setThemeName(
046                        HttpServletRequest request, @Nullable HttpServletResponse response, @Nullable String themeName) {
047
048                throw new UnsupportedOperationException("Cannot change theme - use a different theme resolution strategy");
049        }
050
051}