Java tutorial
/* * Copyright 2008-present MongoDB, Inc. * * 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 com.mongodb.async; import java.io.Closeable; import java.util.List; /** * MongoDB returns query results as batches, and this interface provides an asynchronous iterator over those batches. The first call to * the {@code next} method will return the first batch, and subsequent calls will trigger an asynchronous request to get the next batch * of results. Clients can control the batch size by setting the {@code batchSize} property between calls to {@code next}. * * @since 3.0 * * @param <T> The type of documents the cursor contains * @mongodb.driver.manual ../meta-driver/latest/legacy/mongodb-wire-protocol/#wire-op-get-more OP_GET_MORE * @deprecated Prefer the Reactive Streams-based asynchronous driver (mongodb-driver-reactivestreams artifactId) */ @Deprecated public interface AsyncBatchCursor<T> extends Closeable { /** * Returns the next batch of results. A tailable cursor will block until another batch exists. After the last batch, the next call * to this method will execute the callback with a null result to indicate that there are no more batches available and the cursor * has been closed. * * @param callback callback to receive the next batch of results * @throws java.util.NoSuchElementException if no next batch exists */ void next(SingleResultCallback<List<T>> callback); /** * A special {@code next()} case that returns the next batch if available or null. * * <p>Tailable cursors are an example where this is useful. A call to {@code tryNext()} may return null, but in the future calling * {@code tryNext()} would return a new batch if a document had been added to the capped collection.</p> * * @param callback callback to receive the next batch of results * @since 3.6 * @mongodb.driver.manual reference/glossary/#term-tailable-cursor Tailable Cursor */ void tryNext(SingleResultCallback<List<T>> callback); /** * Sets the batch size to use when requesting the next batch. This is the number of documents to request in the next batch. * * @param batchSize the non-negative batch size. 0 means to use the server default. */ void setBatchSize(int batchSize); /** * Gets the batch size to use when requesting the next batch. This is the number of documents to request in the next batch. * * @return the non-negative batch size. 0 means to use the server default. */ int getBatchSize(); /** * Return true if the AsyncBatchCursor has been closed * * @return true if the AsyncBatchCursor has been closed */ boolean isClosed(); @Override void close(); }