NotificationSubjectHandlerMethodArgumentResolver.java

/*
 * Copyright 2013-2014 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.cloud.aws.messaging.endpoint;

import com.fasterxml.jackson.databind.JsonNode;
import org.springframework.cloud.aws.messaging.config.annotation.NotificationSubject;
import org.springframework.core.MethodParameter;
import org.springframework.http.HttpInputMessage;
import org.springframework.util.ClassUtils;

/**
 * @author Agim Emruli
 */
public class NotificationSubjectHandlerMethodArgumentResolver extends AbstractNotificationMessageHandlerMethodArgumentResolver {

    @Override
    public boolean supportsParameter(MethodParameter parameter) {
        return (parameter.hasParameterAnnotation(NotificationSubject.class) &&
                ClassUtils.isAssignable(String.class, parameter.getParameterType()));
    }

    @Override
    protected Object doResolveArgumentFromNotificationMessage(JsonNode content, HttpInputMessage request, Class<?> parameterType) {
        if (!"Notification".equals(content.get("Type").asText())) {
            throw new IllegalArgumentException("@NotificationMessage annotated parameters are only allowed for method that receive a notification message.");
        }
        return content.findPath("Subject").asText();
    }
}