| /** |
| * 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.feed; |
| |
| import java.util.Date; |
| import java.util.List; |
| |
| import org.apache.camel.Exchange; |
| import org.apache.camel.Processor; |
| |
| /** |
| * Consumer to poll feeds and return each entry from the feed step by step. |
| */ |
| public abstract class FeedEntryPollingConsumer extends FeedPollingConsumer { |
| protected int entryIndex; |
| protected EntryFilter entryFilter; |
| protected List list; |
| protected boolean throttleEntries; |
| protected Object feed; |
| |
| public FeedEntryPollingConsumer(FeedEndpoint endpoint, Processor processor, boolean filter, Date lastUpdate, boolean throttleEntries) { |
| super(endpoint, processor); |
| if (filter) { |
| entryFilter = createEntryFilter(lastUpdate); |
| } |
| this.throttleEntries = throttleEntries; |
| } |
| |
| public int poll() throws Exception { |
| if (feed == null) { |
| // populate new feed |
| feed = createFeed(); |
| populateList(feed); |
| } |
| |
| int polledMessages = 0; |
| while (hasNextEntry()) { |
| Object entry = list.get(entryIndex--); |
| polledMessages++; |
| |
| boolean valid = true; |
| if (entryFilter != null) { |
| valid = entryFilter.isValidEntry(endpoint, feed, entry); |
| } |
| if (valid) { |
| Exchange exchange = endpoint.createExchange(feed, entry); |
| getProcessor().process(exchange); |
| if (this.throttleEntries) { |
| // return and wait for the next poll to continue from last time (this consumer is stateful) |
| return polledMessages; |
| } |
| } |
| } |
| |
| // reset feed and list to be able to poll again |
| feed = null; |
| resetList(); |
| |
| return polledMessages; |
| } |
| |
| protected abstract EntryFilter createEntryFilter(Date lastUpdate); |
| |
| protected abstract void resetList(); |
| |
| protected abstract void populateList(Object feed) throws Exception; |
| |
| private boolean hasNextEntry() { |
| return entryIndex >= 0; |
| } |
| } |