001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.juneau.http.annotation; 018 019import static java.lang.annotation.ElementType.*; 020import static java.lang.annotation.RetentionPolicy.*; 021 022import java.lang.annotation.*; 023 024import org.apache.juneau.annotation.*; 025import org.apache.juneau.httppart.*; 026import org.apache.juneau.oapi.*; 027 028/** 029 * REST request header annotation. 030 * 031 * <p> 032 * Identifies a POJO to be used as the header of an HTTP request. 033 * 034 * <p> 035 * Can be used in the following locations: 036 * <ul> 037 * <li>Arguments and argument-types of server-side <ja>@RestOp</ja>-annotated methods. 038 * <li>Arguments and argument-types of client-side <ja>@RemoteResource</ja>-annotated interfaces. 039 * <li>Methods and return types of server-side and client-side <ja>@Request</ja>-annotated interfaces. 040 * </ul> 041 * 042 * <h5 class='topic'>Arguments and argument-types of server-side @RestOp-annotated methods</h5> 043 * <p> 044 * Annotation that can be applied to a parameter of a <ja>@RestOp</ja>-annotated method to identify it as a HTTP 045 * request header. 046 * 047 * <h5 class='section'>Example:</h5> 048 * <p class='bjava'> 049 * <ja>@RestGet</ja> 050 * <jk>public void</jk> doGet(<ja>@Header</ja>(<js>"ETag"</js>) UUID <jv>etag</jv>) {...} 051 * </p> 052 * 053 * <p> 054 * This is functionally equivalent to the following code... 055 * <p class='bjava'> 056 * <ja>@RestGet</ja> 057 * <jk>public void</jk> doGet(RestRequest <jv>req</jv>, RestResponse <jv>res</jv>) { 058 * UUID <jv>etag</jv> = <jv>req</jv>.getHeader(<js>"ETag"</js>).as(UUID.<jk>class</jk>).orElse(<jk>null</jk>); 059 * ... 060 * } 061 * </p> 062 * 063 * <h5 class='section'>See Also:</h5><ul> 064 * <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JuneauBeanSwagger2">juneau-bean-swagger-v2</a> 065 * <li class='extlink'><a class='doclink' href='https://swagger.io/specification/v2#parameterObject'>Swagger Parameter Object</a> 066 * </ul> 067 * 068 * <h5 class='topic'>Arguments and argument-types of client-side @RemoteResource-annotated interfaces</h5> 069 * <p> 070 * Annotation applied to Java method arguments of interface proxies to denote that they are serialized as an HTTP 071 * header value. 072 * 073 * <h5 class='section'>See Also:</h5><ul> 074 * <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/Header">@Header</a> 075 * </ul> 076 * 077 * <h5 class='topic'>Methods and return types of server-side and client-side @Request-annotated interfaces</h5> 078 * <p> 079 * <h5 class='section'>See Also:</h5><ul> 080 * <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/Request">@Request</a> 081 * </ul> 082 * <p> 083 */ 084@Documented 085@Target({ PARAMETER, METHOD, TYPE, FIELD }) 086@Retention(RUNTIME) 087@Inherited 088@Repeatable(HeaderAnnotation.Array.class) 089@ContextApply(HeaderAnnotation.Applier.class) 090public @interface Header { 091 092 /** 093 * Default value for this parameter. 094 * 095 * @return The annotation value. 096 */ 097 String def() default ""; 098 099 /** 100 * Optional description for the exposed API. 101 * 102 * @return The annotation value. 103 * @since 9.2.0 104 */ 105 String[] description() default {}; 106 107 /** 108 * HTTP header name. 109 * <p> 110 * A blank value (the default) indicates to reuse the bean property name when used on a request bean property. 111 * 112 * <p> 113 * The value should be either a valid HTTP header name, or <js>"*"</js> to represent multiple name/value pairs 114 * 115 * <p> 116 * A blank value (the default) has the following behavior: 117 * <ul class='spaced-list'> 118 * <li> 119 * If the data type is <c>NameValuePairs</c>, <c>Map</c>, or a bean, 120 * then it's the equivalent to <js>"*"</js> which will cause the value to be serialized as name/value pairs. 121 * 122 * <h5 class='figure'>Examples:</h5> 123 * <p class='bjava'> 124 * <jc>// When used on a REST method</jc> 125 * <ja>@RestPost</ja>(<js>"/addPet"</js>) 126 * <jk>public void</jk> addPet(<ja>@Header</ja> JsonMap <jv>allHeaderParameters</jv>) {...} 127 * </p> 128 * <p class='bjava'> 129 * <jc>// When used on a remote method parameter</jc> 130 * <ja>@RemoteResource</ja>(path=<js>"/myproxy"</js>) 131 * <jk>public interface</jk> MyProxy { 132 * 133 * <jc>// Equivalent to @Header("*")</jc> 134 * <ja>@RemoteGet</ja>(<js>"/mymethod"</js>) 135 * String myProxyMethod1(<ja>@Header</ja> Map<String,Object> <jv>allHeaderParameters</jv>); 136 * } 137 * </p> 138 * <p class='bjava'> 139 * <jc>// When used on a request bean method</jc> 140 * <jk>public interface</jk> MyRequest { 141 * 142 * <jc>// Equivalent to @Header("*")</jc> 143 * <ja>@Header</ja> 144 * Map<String,Object> getFoo(); 145 * } 146 * </p> 147 * </li> 148 * <li> 149 * If used on a request bean method, uses the bean property name. 150 * 151 * <h5 class='figure'>Example:</h5> 152 * <p class='bjava'> 153 * <jk>public interface</jk> MyRequest { 154 * 155 * <jc>// Equivalent to @Header("Foo")</jc> 156 * <ja>@Header</ja> 157 * <ja>@Beanp</ja>(<js>"Foo"</js>) 158 * String getFoo(); 159 * } 160 * </p> 161 * </li> 162 * </ul> 163 * 164 * @return The annotation value. 165 */ 166 String name() default ""; 167 168 /** 169 * Dynamically apply this annotation to the specified classes. 170 * 171 * <h5 class='section'>See Also:</h5><ul> 172 * <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/DynamicallyAppliedAnnotations">Dynamically Applied Annotations</a> 173 * </ul> 174 * 175 * @return The annotation value. 176 */ 177 String[] on() default {}; 178 179 /** 180 * Dynamically apply this annotation to the specified classes. 181 * 182 * <p> 183 * Identical to {@link #on()} except allows you to specify class objects instead of a strings. 184 * 185 * <h5 class='section'>See Also:</h5><ul> 186 * <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/DynamicallyAppliedAnnotations">Dynamically Applied Annotations</a> 187 * </ul> 188 * 189 * @return The annotation value. 190 */ 191 Class<?>[] onClass() default {}; 192 193 /** 194 * Specifies the {@link HttpPartParser} class used for parsing strings to values. 195 * 196 * <p> 197 * Overrides for this part the part parser defined on the REST resource which by default is {@link OpenApiParser}. 198 * 199 * @return The annotation value. 200 */ 201 Class<? extends HttpPartParser> parser() default HttpPartParser.Void.class; 202 203 /** 204 * <mk>schema</mk> field of the <a class='doclink' href='https://swagger.io/specification/v2#parameterObject'>Swagger Parameter Object</a>. 205 * 206 * <p> 207 * The schema defining the type used for parameter. 208 * 209 * <p> 210 * The {@link Schema @Schema} annotation can also be used standalone on the parameter or type. 211 * Values specified on this field override values specified on the type, and values specified on child types override values 212 * specified on parent types. 213 * 214 * <h5 class='section'>Used for:</h5> 215 * <ul class='spaced-list'> 216 * <li> 217 * Server-side schema-based parsing and parsing validation. 218 * <li> 219 * Server-side generated Swagger documentation. 220 * <li> 221 * Client-side schema-based serializing and serializing validation. 222 * </ul> 223 * 224 * @return The annotation value. 225 */ 226 Schema schema() default @Schema; 227 228 /** 229 * Specifies the {@link HttpPartSerializer} class used for serializing values to strings. 230 * 231 * <p> 232 * Overrides for this part the part serializer defined on the REST client which by default is {@link OpenApiSerializer}. 233 * 234 * @return The annotation value. 235 */ 236 Class<? extends HttpPartSerializer> serializer() default HttpPartSerializer.Void.class; 237 238 /** 239 * A synonym for {@link #name()}. 240 * 241 * <p> 242 * Allows you to use shortened notation if you're only specifying the name. 243 * 244 * <p> 245 * The following are completely equivalent ways of defining a header entry: 246 * <p class='bjava'> 247 * <jk>public</jk> Order placeOrder(<ja>@Header</ja>(name=<js>"api_key"</js>) String <jv>apiKey</jv>) {...} 248 * </p> 249 * <p class='bjava'> 250 * <jk>public</jk> Order placeOrder(<ja>@Header</ja>(<js>"api_key"</js>) String <jv>apiKey</jv>) {...} 251 * </p> 252 * 253 * @return The annotation value. 254 */ 255 String value() default ""; 256}