/*
 * Copyright 2002-2018 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
 *
 *      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.springframework.validation.support;

import java.util.Map;

import org.springframework.ui.ConcurrentModel;
import org.springframework.validation.BindingResult;

Subclass of ConcurrentModel that automatically removes the BindingResult object when its corresponding target attribute is replaced through regular Map operations. 
This is the class exposed to handler methods by Spring WebFlux, typically consumed through a declaration of the Model interface as a parameter type. There is typically no need to create it within user code. If necessary a handler method can return a regular java.util.Map, likely a java.util.ConcurrentMap, for a pre-determined model. 
Author:
Rossen Stoyanchev
See Also:
BindingResult
Since:
5.0/**
 * Subclass of {@link ConcurrentModel} that automatically removes
 * the {@link BindingResult} object when its corresponding
 * target attribute is replaced through regular {@link Map} operations.
 *
 * <p>This is the class exposed to handler methods by Spring WebFlux,
 * typically consumed through a declaration of the
 * {@link org.springframework.ui.Model} interface as a parameter type.
 * There is typically no need to create it within user code.
 * If necessary a handler method can return a regular {@code java.util.Map},
 * likely a {@code java.util.ConcurrentMap}, for a pre-determined model.
 *
 * @author Rossen Stoyanchev
 * @since 5.0
 * @see BindingResult
 */
@SuppressWarnings("serial")
public class BindingAwareConcurrentModel extends ConcurrentModel {

	@Override
	public Object put(String key, Object value) {
		removeBindingResultIfNecessary(key, value);
		return super.put(key, value);
	}

	private void removeBindingResultIfNecessary(String key, Object value) {
		if (!key.startsWith(BindingResult.MODEL_KEY_PREFIX)) {
			String resultKey = BindingResult.MODEL_KEY_PREFIX + key;
			BindingResult result = (BindingResult) get(resultKey);
			if (result != null && result.getTarget() != value) {
				remove(resultKey);
			}
		}
	}

}