Java tutorial
/* * Copyright 2002-2012 the original author or authors. * * Licensed 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 * * https://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.springframework.web.bind.annotation; /** * Common value constants shared between bind annotations. * * @author Juergen Hoeller * @since 3.0.1 */ public interface ValueConstants { /** * Constant defining a value for no default - as a replacement for * {@code null} which we cannot use in annotation attributes. * <p>This is an artificial arrangement of 16 unicode characters, * with its sole purpose being to never match user-declared values. * @see RequestParam#defaultValue() * @see RequestHeader#defaultValue() * @see CookieValue#defaultValue() */ String DEFAULT_NONE = "\n\t\t\n\t\t\n\uE000\uE001\uE002\n\t\t\t\t\n"; }