Java tutorial
/** * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.apache.camel.component.gridfs; import java.io.InputStream; import java.util.concurrent.ExecutorService; import com.mongodb.BasicDBObject; import com.mongodb.BasicDBObjectBuilder; import com.mongodb.DBCollection; import com.mongodb.DBCursor; import com.mongodb.DBObject; import com.mongodb.MongoException; import com.mongodb.gridfs.GridFSDBFile; import com.mongodb.util.JSON; import org.apache.camel.Exchange; import org.apache.camel.Processor; import org.apache.camel.component.gridfs.GridFsEndpoint.QueryStrategy; import org.apache.camel.impl.DefaultConsumer; /** * */ public class GridFsConsumer extends DefaultConsumer implements Runnable { final GridFsEndpoint endpoint; private ExecutorService executor; /** * @param endpoint * @param processor */ public GridFsConsumer(GridFsEndpoint endpoint, Processor processor) { super(endpoint, processor); this.endpoint = endpoint; } @Override protected void doStop() throws Exception { super.doStop(); if (executor != null) { executor.shutdown(); executor = null; } } @Override protected void doStart() throws Exception { super.doStart(); executor = endpoint.getCamelContext().getExecutorServiceManager().newFixedThreadPool(this, endpoint.getEndpointUri(), 1); executor.execute(this); } @Override public void run() { DBCursor c = null; java.util.Date fromDate = null; QueryStrategy s = endpoint.getQueryStrategy(); boolean usesTimestamp = (s != QueryStrategy.FileAttribute); boolean persistsTimestamp = (s == QueryStrategy.PersistentTimestamp || s == QueryStrategy.PersistentTimestampAndFileAttribute); boolean usesAttribute = (s == QueryStrategy.FileAttribute || s == QueryStrategy.TimeStampAndFileAttribute || s == QueryStrategy.PersistentTimestampAndFileAttribute); DBCollection ptsCollection = null; DBObject persistentTimestamp = null; if (persistsTimestamp) { ptsCollection = endpoint.getDB().getCollection(endpoint.getPersistentTSCollection()); // ensure standard indexes as long as collections are small try { if (ptsCollection.count() < 1000) { ptsCollection.createIndex(new BasicDBObject("id", 1)); } } catch (MongoException e) { //TODO: Logging } persistentTimestamp = ptsCollection.findOne(new BasicDBObject("id", endpoint.getPersistentTSObject())); if (persistentTimestamp == null) { persistentTimestamp = new BasicDBObject("id", endpoint.getPersistentTSObject()); fromDate = new java.util.Date(); persistentTimestamp.put("timestamp", fromDate); ptsCollection.save(persistentTimestamp); } fromDate = (java.util.Date) persistentTimestamp.get("timestamp"); } else if (usesTimestamp) { fromDate = new java.util.Date(); } try { Thread.sleep(endpoint.getInitialDelay()); while (isStarted()) { if (c == null || c.getCursorId() == 0) { if (c != null) { c.close(); } String queryString = endpoint.getQuery(); DBObject query; if (queryString == null) { query = new BasicDBObject(); } else { query = (DBObject) JSON.parse(queryString); } if (usesTimestamp) { query.put("uploadDate", new BasicDBObject("$gt", fromDate)); } if (usesAttribute) { query.put(endpoint.getFileAttributeName(), null); } c = endpoint.getFilesCollection().find(query); } boolean dateModified = false; while (c.hasNext() && isStarted()) { GridFSDBFile file = (GridFSDBFile) c.next(); GridFSDBFile forig = file; if (usesAttribute) { file.put(endpoint.getFileAttributeName(), "processing"); DBObject q = BasicDBObjectBuilder.start("_id", file.getId()).append("camel-processed", null) .get(); forig = (GridFSDBFile) endpoint.getFilesCollection().findAndModify(q, null, null, false, file, true, false); } if (forig != null) { file = endpoint.getGridFs().findOne(new BasicDBObject("_id", file.getId())); Exchange exchange = endpoint.createExchange(); exchange.getIn().setHeader(GridFsEndpoint.GRIDFS_METADATA, JSON.serialize(file.getMetaData())); exchange.getIn().setHeader(Exchange.FILE_CONTENT_TYPE, file.getContentType()); exchange.getIn().setHeader(Exchange.FILE_LENGTH, file.getLength()); exchange.getIn().setHeader(Exchange.FILE_LAST_MODIFIED, file.getUploadDate()); exchange.getIn().setBody(file.getInputStream(), InputStream.class); try { getProcessor().process(exchange); //System.out.println("Processing " + file.getFilename()); if (usesAttribute) { forig.put(endpoint.getFileAttributeName(), "done"); endpoint.getFilesCollection().save(forig); } if (usesTimestamp) { if (file.getUploadDate().compareTo(fromDate) > 0) { fromDate = file.getUploadDate(); dateModified = true; } } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } if (persistsTimestamp && dateModified) { persistentTimestamp.put("timestamp", fromDate); ptsCollection.save(persistentTimestamp); } Thread.sleep(endpoint.getDelay()); } } catch (Throwable e1) { // TODO Auto-generated catch block e1.printStackTrace(); } if (c != null) { c.close(); } } }