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.util;
018
019import java.net.URI;
020import java.net.URISyntaxException;
021import java.util.Collections;
022import java.util.HashMap;
023import java.util.Map;
024
025import org.springframework.lang.Nullable;
026import org.springframework.util.Assert;
027
028/**
029 * Abstract base class for {@link UriTemplateHandler} implementations.
030 *
031 * <p>Support {@link #setBaseUrl} and {@link #setDefaultUriVariables} properties
032 * that should be relevant regardless of the URI template expand and encode
033 * mechanism used in sub-classes.
034 *
035 * @author Rossen Stoyanchev
036 * @since 4.3
037 * @deprecated as of 5.0 in favor of {@link DefaultUriBuilderFactory}
038 */
039@Deprecated
040public abstract class AbstractUriTemplateHandler implements UriTemplateHandler {
041
042        @Nullable
043        private String baseUrl;
044
045        private final Map<String, Object> defaultUriVariables = new HashMap<>();
046
047
048        /**
049         * Configure a base URL to prepend URI templates with. The base URL must
050         * have a scheme and host but may optionally contain a port and a path.
051         * The base URL must be fully expanded and encoded which can be done via
052         * {@link UriComponentsBuilder}.
053         * @param baseUrl the base URL.
054         */
055        public void setBaseUrl(@Nullable String baseUrl) {
056                if (baseUrl != null) {
057                        UriComponents uriComponents = UriComponentsBuilder.fromUriString(baseUrl).build();
058                        Assert.hasText(uriComponents.getScheme(), "'baseUrl' must have a scheme");
059                        Assert.hasText(uriComponents.getHost(), "'baseUrl' must have a host");
060                        Assert.isNull(uriComponents.getQuery(), "'baseUrl' cannot have a query");
061                        Assert.isNull(uriComponents.getFragment(), "'baseUrl' cannot have a fragment");
062                }
063                this.baseUrl = baseUrl;
064        }
065
066        /**
067         * Return the configured base URL.
068         */
069        @Nullable
070        public String getBaseUrl() {
071                return this.baseUrl;
072        }
073
074        /**
075         * Configure default URI variable values to use with every expanded URI
076         * template. These default values apply only when expanding with a Map, and
077         * not with an array, where the Map supplied to {@link #expand(String, Map)}
078         * can override the default values.
079         * @param defaultUriVariables the default URI variable values
080         * @since 4.3
081         */
082        public void setDefaultUriVariables(@Nullable Map<String, ?> defaultUriVariables) {
083                this.defaultUriVariables.clear();
084                if (defaultUriVariables != null) {
085                        this.defaultUriVariables.putAll(defaultUriVariables);
086                }
087        }
088
089        /**
090         * Return a read-only copy of the configured default URI variables.
091         */
092        public Map<String, ?> getDefaultUriVariables() {
093                return Collections.unmodifiableMap(this.defaultUriVariables);
094        }
095
096
097        @Override
098        public URI expand(String uriTemplate, Map<String, ?> uriVariables) {
099                if (!getDefaultUriVariables().isEmpty()) {
100                        Map<String, Object> map = new HashMap<>();
101                        map.putAll(getDefaultUriVariables());
102                        map.putAll(uriVariables);
103                        uriVariables = map;
104                }
105                URI url = expandInternal(uriTemplate, uriVariables);
106                return insertBaseUrl(url);
107        }
108
109        @Override
110        public URI expand(String uriTemplate, Object... uriVariables) {
111                URI url = expandInternal(uriTemplate, uriVariables);
112                return insertBaseUrl(url);
113        }
114
115
116        /**
117         * Actually expand and encode the URI template.
118         */
119        protected abstract URI expandInternal(String uriTemplate, Map<String, ?> uriVariables);
120
121        /**
122         * Actually expand and encode the URI template.
123         */
124        protected abstract URI expandInternal(String uriTemplate, Object... uriVariables);
125
126
127        /**
128         * Insert a base URL (if configured) unless the given URL has a host already.
129         */
130        private URI insertBaseUrl(URI url) {
131                try {
132                        String baseUrl = getBaseUrl();
133                        if (baseUrl != null && url.getHost() == null) {
134                                url = new URI(baseUrl + url.toString());
135                        }
136                        return url;
137                }
138                catch (URISyntaxException ex) {
139                        throw new IllegalArgumentException("Invalid URL after inserting base URL: " + url, ex);
140                }
141        }
142
143}