MutualFileAccessControl.java

/*
 * Copyright (c) 2013 Technische Universitat Wien (TUW), Distributed Systems Group. http://dsg.tuwien.ac.at
 *
 * This work was partially supported by the European Commission in terms of the CELAR FP7 project (FP7-ICT-2011-8 #317790), http://www.celarcloud.eu/
 *
 *    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 at.ac.tuwien.dsg.cloud.salsa.engine.utils;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class MutualFileAccessControl {
	
	static private boolean AccessingFile = false;
	
	public static void lockFile(){
		while (AccessingFile) {
			try {
				Thread.sleep(1000);
			} catch (Exception e) {
			}
		}
		AccessingFile = true;
	}
	
	public static void releaseFile(){
		AccessingFile = false;
	}
	
	// save uploaded file to new location
	public static void writeToFile(InputStream uploadedInputStream,
			String uploadedFileLocation) {	
		try {
			OutputStream out = new FileOutputStream(new File(
					uploadedFileLocation));
			int read = 0;
			byte[] bytes = new byte[1024];
			
			while ((read = uploadedInputStream.read(bytes)) != -1) {
				out.write(bytes, 0, read);
			}
			out.flush();
			out.close();
		} catch (IOException e) {			
			EngineLogger.logger.error("Error writing to file: "	+ uploadedFileLocation);
			EngineLogger.logger.error(e.toString());
		}		
	}
}