Uploader.java

/**
 * TNTConcept Easy Enterprise Management by Autentia Real Bussiness Solution S.L.
 * Copyright (C) 2007 Autentia Real Bussiness Solution S.L.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * 
 */
package com.autentia.tnt.upload;

import java.io.*;
import org.apache.myfaces.custom.fileupload.UploadedFile;

/**
 * Interface for uploading files. An Uploader is responsible for storing uploaded files
 * in its correct place.
 * @author ivan
 */
public interface Uploader 
{
	/**
	 * Store an uploaded file under the object with specified id. If the file exists
	 * it is overwritten.
	 * @param id id of object (can be null if file is not associated to object)
	 * @param file uploaded file
	 */
	public void store( String id, UploadedFile file ) throws IOException;

	/**
	 * Replace an existing uploaded file under the object with specified id
	 * @param id id of object (can be null if file is not associated to object)
	 * @param oldFile old uploaded file (if it is null, the method works as store)
	 * @param newFile uploaded file
	 */
	public void replace( String id, String oldFile, UploadedFile newFile ) throws IOException;

	/**
	 * Version an existing file. The old file is renamed with a leading version number.
	 * The new file name is not taken into account, the old name is always used.
	 * @param id id of object
	 * @param oldFile old file name (if it is null, the method works as store)
	 * @param newFile new uploaded file
	 * 
	 * @return versioned file name
	 */
	public String version( String id, String oldFile, UploadedFile newFile ) throws IOException;

	/**
	 * Check if a file exists under the specified object
	 * @param id id of object (can be null if file is not associated to object)
	 * @param file file to check for
	 * @return true if the file exists
	 */
	public boolean exists( String id, String file );
	
	/**
	 * Delete an existing file. 
	 * @param id id of object (can be null if file is not associated to object)
	 * @param file file name
	 * @return false it the file does not exist, true if the file existed and could be deleted
	 * @throws IOException if the file exists and cannot be deleted
	 */
	public boolean delete( String id, String file ) throws IOException;
}