AttrWorker.java

//
// typica - A client library for Amazon Web Services
// Copyright (C) 2007 Xerox Corporation
// 
// 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.xerox.amazonws.sdb;

import java.util.List;
import java.util.Map;

/**
 * This class handles threaded attribute fetching from SimpleDB.
 *
 * @author D. Kavanagh
 * @author developer@dotech.com
 */
class AttrWorker implements Runnable {
	private Item item;
	private Counter running;
	private Map<String, List<ItemAttribute>> results;
	private ItemListener listener;

	public AttrWorker(Item item, Counter running, Map<String, List<ItemAttribute>> results, ItemListener listener) {
		this.item = item;
		this.running = running;
		this.results = results;
		this.listener = listener;
	}

	public void run() {
		boolean done = false;
		while (!done) {
			try {
				if (results != null) {
					results.put(item.getIdentifier(), item.getAttributes());
				}
				else if (listener != null) {
					listener.itemAvailable(item.getIdentifier(), item.getAttributes());
				}
				done = true;
			} catch (SDBException sdbex) {
				System.err.println("some sdb error, retrying... "+sdbex.getMessage());
			}
			finally {
				synchronized (running) {
					running.decrement();
				}
			}
		}
	}
}