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See the License for the * 011// * specific language governing permissions and limitations under the License. * 012// *************************************************************************************************************************** 013package org.apache.juneau.http.annotation; 014 015import static java.lang.annotation.ElementType.*; 016import static java.lang.annotation.RetentionPolicy.*; 017 018import java.lang.annotation.*; 019 020import org.apache.juneau.annotation.*; 021import org.apache.juneau.httppart.*; 022import org.apache.juneau.oapi.*; 023 024/** 025 * REST request header annotation. 026 * 027 * <p> 028 * Identifies a POJO to be used as the header of an HTTP request. 029 * 030 * <p> 031 * Can be used in the following locations: 032 * <ul> 033 * <li>Arguments and argument-types of server-side <ja>@RestOp</ja>-annotated methods. 034 * <li>Arguments and argument-types of client-side <ja>@RemoteResource</ja>-annotated interfaces. 035 * <li>Methods and return types of server-side and client-side <ja>@Request</ja>-annotated interfaces. 036 * </ul> 037 * 038 * <h5 class='topic'>Arguments and argument-types of server-side @RestOp-annotated methods</h5> 039 * <p> 040 * Annotation that can be applied to a parameter of a <ja>@RestOp</ja>-annotated method to identify it as a HTTP 041 * request header. 042 * 043 * <h5 class='section'>Example:</h5> 044 * <p class='bjava'> 045 * <ja>@RestGet</ja> 046 * <jk>public void</jk> doGet(<ja>@Header</ja>(<js>"ETag"</js>) UUID <jv>etag</jv>) {...} 047 * </p> 048 * 049 * <p> 050 * This is functionally equivalent to the following code... 051 * <p class='bjava'> 052 * <ja>@RestGet</ja> 053 * <jk>public void</jk> doGet(RestRequest <jv>req</jv>, RestResponse <jv>res</jv>) { 054 * UUID <jv>etag</jv> = <jv>req</jv>.getHeader(<js>"ETag"</js>).as(UUID.<jk>class</jk>).orElse(<jk>null</jk>); 055 * ... 056 * } 057 * </p> 058 * 059 * <h5 class='section'>See Also:</h5><ul> 060 * <li class='link'><a class="doclink" href="../../../../../index.html#jrs.Swagger">Swagger</a> 061 * <li class='extlink'><a class='doclink' href='https://swagger.io/specification/v2#parameterObject'>Swagger Parameter Object</a> 062 * </ul> 063 * 064 * <h5 class='topic'>Arguments and argument-types of client-side @RemoteResource-annotated interfaces</h5> 065 * <p> 066 * Annotation applied to Java method arguments of interface proxies to denote that they are serialized as an HTTP 067 * header value. 068 * 069 * <h5 class='section'>See Also:</h5><ul> 070 * <li class='link'><a class="doclink" href="../../../../../index.html#jrc.Header">@Header</a> 071 * </ul> 072 * 073 * <h5 class='topic'>Methods and return types of server-side and client-side @Request-annotated interfaces</h5> 074 * <p> 075 * <h5 class='section'>See Also:</h5><ul> 076 * <li class='link'><a class="doclink" href="../../../../../index.html#jrc.Request">@Request</a> 077 * </ul> 078 * <p> 079 * <h5 class='section'>See Also:</h5><ul> 080 081 * </ul> 082 */ 083@Documented 084@Target({PARAMETER,METHOD,TYPE,FIELD}) 085@Retention(RUNTIME) 086@Inherited 087@Repeatable(HeaderAnnotation.Array.class) 088@ContextApply(HeaderAnnotation.Applier.class) 089public @interface Header { 090 091 /** 092 * Default value for this parameter. 093 * 094 * @return The annotation value. 095 */ 096 String def() default ""; 097 098 /** 099 * HTTP header name. 100 * <p> 101 * A blank value (the default) indicates to reuse the bean property name when used on a request bean property. 102 * 103 * <p> 104 * The value should be either a valid HTTP header name, or <js>"*"</js> to represent multiple name/value pairs 105 * 106 * <p> 107 * A blank value (the default) has the following behavior: 108 * <ul class='spaced-list'> 109 * <li> 110 * If the data type is <c>NameValuePairs</c>, <c>Map</c>, or a bean, 111 * then it's the equivalent to <js>"*"</js> which will cause the value to be serialized as name/value pairs. 112 * 113 * <h5 class='figure'>Examples:</h5> 114 * <p class='bjava'> 115 * <jc>// When used on a REST method</jc> 116 * <ja>@RestPost</ja>(<js>"/addPet"</js>) 117 * <jk>public void</jk> addPet(<ja>@Header</ja> JsonMap <jv>allHeaderParameters</jv>) {...} 118 * </p> 119 * <p class='bjava'> 120 * <jc>// When used on a remote method parameter</jc> 121 * <ja>@RemoteResource</ja>(path=<js>"/myproxy"</js>) 122 * <jk>public interface</jk> MyProxy { 123 * 124 * <jc>// Equivalent to @Header("*")</jc> 125 * <ja>@RemoteGet</ja>(<js>"/mymethod"</js>) 126 * String myProxyMethod1(<ja>@Header</ja> Map<String,Object> <jv>allHeaderParameters</jv>); 127 * } 128 * </p> 129 * <p class='bjava'> 130 * <jc>// When used on a request bean method</jc> 131 * <jk>public interface</jk> MyRequest { 132 * 133 * <jc>// Equivalent to @Header("*")</jc> 134 * <ja>@Header</ja> 135 * Map<String,Object> getFoo(); 136 * } 137 * </p> 138 * </li> 139 * <li> 140 * If used on a request bean method, uses the bean property name. 141 * 142 * <h5 class='figure'>Example:</h5> 143 * <p class='bjava'> 144 * <jk>public interface</jk> MyRequest { 145 * 146 * <jc>// Equivalent to @Header("Foo")</jc> 147 * <ja>@Header</ja> 148 * <ja>@Beanp</ja>(<js>"Foo"</js>) 149 * String getFoo(); 150 * } 151 * </p> 152 * </li> 153 * </ul> 154 * 155 * @return The annotation value. 156 */ 157 String name() default ""; 158 159 /** 160 * Dynamically apply this annotation to the specified classes. 161 * 162 * <h5 class='section'>See Also:</h5><ul> 163 * <li class='link'><a class="doclink" href="../../../../../index.html#jm.DynamicallyAppliedAnnotations">Dynamically Applied Annotations</a> 164 * </ul> 165 * 166 * @return The annotation value. 167 */ 168 String[] on() default {}; 169 170 /** 171 * Dynamically apply this annotation to the specified classes. 172 * 173 * <p> 174 * Identical to {@link #on()} except allows you to specify class objects instead of a strings. 175 * 176 * <h5 class='section'>See Also:</h5><ul> 177 * <li class='link'><a class="doclink" href="../../../../../index.html#jm.DynamicallyAppliedAnnotations">Dynamically Applied Annotations</a> 178 * </ul> 179 * 180 * @return The annotation value. 181 */ 182 Class<?>[] onClass() default {}; 183 184 /** 185 * Specifies the {@link HttpPartParser} class used for parsing strings to values. 186 * 187 * <p> 188 * Overrides for this part the part parser defined on the REST resource which by default is {@link OpenApiParser}. 189 * 190 * @return The annotation value. 191 */ 192 Class<? extends HttpPartParser> parser() default HttpPartParser.Void.class; 193 194 /** 195 * <mk>schema</mk> field of the <a class='doclink' href='https://swagger.io/specification/v2#parameterObject'>Swagger Parameter Object</a>. 196 * 197 * <p> 198 * The schema defining the type used for parameter. 199 * 200 * <p> 201 * The {@link Schema @Schema} annotation can also be used standalone on the parameter or type. 202 * Values specified on this field override values specified on the type, and values specified on child types override values 203 * specified on parent types. 204 * 205 * <h5 class='section'>Used for:</h5> 206 * <ul class='spaced-list'> 207 * <li> 208 * Server-side schema-based parsing and parsing validation. 209 * <li> 210 * Server-side generated Swagger documentation. 211 * <li> 212 * Client-side schema-based serializing and serializing validation. 213 * </ul> 214 * 215 * @return The annotation value. 216 */ 217 Schema schema() default @Schema; 218 219 /** 220 * Specifies the {@link HttpPartSerializer} class used for serializing values to strings. 221 * 222 * <p> 223 * Overrides for this part the part serializer defined on the REST client which by default is {@link OpenApiSerializer}. 224 * 225 * @return The annotation value. 226 */ 227 Class<? extends HttpPartSerializer> serializer() default HttpPartSerializer.Void.class; 228 229 /** 230 * A synonym for {@link #name()}. 231 * 232 * <p> 233 * Allows you to use shortened notation if you're only specifying the name. 234 * 235 * <p> 236 * The following are completely equivalent ways of defining a header entry: 237 * <p class='bjava'> 238 * <jk>public</jk> Order placeOrder(<ja>@Header</ja>(name=<js>"api_key"</js>) String <jv>apiKey</jv>) {...} 239 * </p> 240 * <p class='bjava'> 241 * <jk>public</jk> Order placeOrder(<ja>@Header</ja>(<js>"api_key"</js>) String <jv>apiKey</jv>) {...} 242 * </p> 243 * 244 * @return The annotation value. 245 */ 246 String value() default ""; 247}