/*
* Copyright 2016-2017 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.data.mongodb.repository;
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.data.annotation.QueryAnnotation;
/**
* Annotation to declare an infinite stream using MongoDB's {@link com.mongodb.CursorType#TailableAwait tailable}
* cursors. An infinite stream can only be used with capped collections. Objects are emitted through the stream as data
* is inserted into the collection. An infinite stream can only be used with streams that emit more than one element,
* such as {@link reactor.core.publisher.Flux}.
* <p>
* The stream may become dead, or invalid, if either the query returns no match or the cursor returns the document at
* the "end" of the collection and then the application deletes that document.
* <p>
* A stream that is no longer in use must be {@link reactor.core.Disposable#dispose()} disposed} otherwise the streams
* will linger and exhaust resources.
*
* @author Mark Paluch
* @see <a href="https://docs.mongodb.com/manual/core/tailable-cursors/">Tailable Cursors</a>
* @since 2.0
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.METHOD, ElementType.ANNOTATION_TYPE })
@Documented
@QueryAnnotation
public @interface Tailable {
}