Java tutorial
/* * Copyright 2002-2016 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; import java.lang.annotation.Documented; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; import org.springframework.core.annotation.AliasFor; import org.springframework.ui.Model; /** * Annotation that binds a method parameter or method return value * to a named model attribute, exposed to a web view. Supported * for controller classes with {@link RequestMapping @RequestMapping} * methods. * * <p>Can be used to expose command objects to a web view, using * specific attribute names, through annotating corresponding * parameters of an {@link RequestMapping @RequestMapping} method. * * <p>Can also be used to expose reference data to a web view * through annotating accessor methods in a controller class with * {@link RequestMapping @RequestMapping} methods. Such accessor * methods are allowed to have any arguments that * {@link RequestMapping @RequestMapping} methods support, returning * the model attribute value to expose. * * <p>Note however that reference data and all other model content is * not available to web views when request processing results in an * {@code Exception} since the exception could be raised at any time * making the content of the model unreliable. For this reason * {@link ExceptionHandler @ExceptionHandler} methods do not provide * access to a {@link Model} argument. * * @author Juergen Hoeller * @author Rossen Stoyanchev * @since 2.5 */ @Target({ ElementType.PARAMETER, ElementType.METHOD }) @Retention(RetentionPolicy.RUNTIME) @Documented public @interface ModelAttribute { /** * Alias for {@link #name}. */ @AliasFor("name") String value() default ""; /** * The name of the model attribute to bind to. * <p>The default model attribute name is inferred from the declared * attribute type (i.e. the method parameter type or method return type), * based on the non-qualified class name: * e.g. "orderAddress" for class "mypackage.OrderAddress", * or "orderAddressList" for "List<mypackage.OrderAddress>". * @since 4.3 */ @AliasFor("value") String name() default ""; /** * Allows declaring data binding disabled directly on an {@code @ModelAttribute} * method parameter or on the attribute returned from an {@code @ModelAttribute} * method, both of which would prevent data binding for that attribute. * <p>By default this is set to {@code true} in which case data binding applies. * Set this to {@code false} to disable data binding. * @since 4.3 */ boolean binding() default true; }