Java tutorial
/* * The MIT License * * Copyright (c) 2015, Mahmoud Ben Hassine (mahmoud@benhassine.fr) * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package org.easybatch.extensions.mongodb; import com.mongodb.BulkWriteOperation; import com.mongodb.DBCollection; import com.mongodb.DBObject; import org.easybatch.core.record.Batch; import org.easybatch.core.record.Record; import org.easybatch.core.writer.RecordWriter; import org.easybatch.core.writer.RecordWritingException; import java.util.ArrayList; import java.util.Collection; import java.util.List; import static java.lang.String.format; import static org.easybatch.core.util.Utils.checkNotNull; /** * Writes a batch of {@link MongoDBRecord} to a given collection in bulk mode. * * @author Mahmoud Ben Hassine (mahmoud@benhassine.fr) */ public class MongoDBBatchWriter implements RecordWriter<Batch> { private DBCollection collection; /** * Create a MongoDB batch writer. * * @param collection the collection to write documents to. */ public MongoDBBatchWriter(final DBCollection collection) { checkNotNull(collection, "collection"); this.collection = collection; } @Override public Batch processRecord(final Batch batch) throws RecordWritingException { List<Record> records = batch.getPayload(); Collection<DBObject> documents = asDocuments(records); BulkWriteOperation bulkWriteOperation = collection.initializeOrderedBulkOperation(); for (DBObject document : documents) { bulkWriteOperation.insert(document); } try { bulkWriteOperation.execute(); return batch; } catch (Exception e) { throw new RecordWritingException(format("Unable to write documents [%s] to Mongo DB server", documents), e); } } private List<DBObject> asDocuments(final List<Record> records) { List<DBObject> documents = new ArrayList<>(); for (Record record : records) { if (record instanceof MongoDBRecord) { MongoDBRecord mongoDBRecord = (MongoDBRecord) record; documents.add(mongoDBRecord.getPayload()); } } return documents; } }