| // *************************************************************************************************************************** |
| // * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * |
| // * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * |
| // * to you 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 * |
| // * * |
| // * http://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.apache.juneau.http; |
| |
| import org.apache.juneau.http.annotation.*; |
| |
| /** |
| * Represents a parsed <l>If-Unmodified-Since</l> HTTP request header. |
| * |
| * <p> |
| * Only send the response if the entity has not been modified since a specific time. |
| * |
| * <h5 class='figure'>Example</h5> |
| * <p class='bcode w800'> |
| * If-Unmodified-Since: Sat, 29 Oct 1994 19:43:31 GMT |
| * </p> |
| * |
| * <h5 class='topic'>RFC2616 Specification</h5> |
| * |
| * The If-Unmodified-Since request-header field is used with a method to make it conditional. |
| * If the requested resource has not been modified since the time specified in this field, the server SHOULD perform the |
| * requested operation as if the If-Unmodified-Since header were not present. |
| * |
| * <p> |
| * If the requested variant has been modified since the specified time, the server MUST NOT perform the requested |
| * operation, and MUST return a 412 (Precondition Failed). |
| * |
| * <p class='bcode w800'> |
| * If-Unmodified-Since = "If-Unmodified-Since" ":" HTTP-date |
| * </p> |
| * |
| * <p> |
| * An example of the field is: |
| * <p class='bcode w800'> |
| * If-Unmodified-Since: Sat, 29 Oct 1994 19:43:31 GMT |
| * </p> |
| * |
| * <p> |
| * If the request normally (i.e., without the If-Unmodified-Since header) would result in anything other than a 2xx or |
| * 412 status, the If-Unmodified-Since header SHOULD be ignored. |
| * |
| * <p> |
| * If the specified date is invalid, the header is ignored. |
| * |
| * <p> |
| * The result of a request having both an If-Unmodified-Since header field and either an If-None-Match or an |
| * If-Modified-Since header fields is undefined by this specification. |
| * |
| * <ul class='seealso'> |
| * <li class='extlink'>{@doc RFC2616} |
| * </ul> |
| */ |
| @Header("If-Unmodified-Since") |
| public final class IfUnmodifiedSince extends HeaderDate { |
| |
| /** |
| * Returns a parsed <c>If-Unmodified-Since</c> header. |
| * |
| * @param value The <c>If-Unmodified-Since</c> header string. |
| * @return The parsed <c>If-Unmodified-Since</c> header, or <jk>null</jk> if the string was null. |
| */ |
| public static IfUnmodifiedSince forString(String value) { |
| if (value == null) |
| return null; |
| return new IfUnmodifiedSince(value); |
| } |
| |
| private IfUnmodifiedSince(String value) { |
| super(value); |
| } |
| } |