view src/org/tmatesoft/hg/util/RegularFileInfo.java @ 338:3cfa4d908fc9

Add options to control DataAccessProvider, allow to turn off use of file memory mapping in particular to solve potential sharing violation (os file handle gets released on MappedByteByffer being GC'd, not on FileChannel.close())
author Artem Tikhomirov <tikhomirov.artem@gmail.com>
date Tue, 15 Nov 2011 04:47:03 +0100
parents 981f9f50bb6c
children 7f27122011c3
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/*
 * Copyright (c) 2011 TMate Software Ltd
 *  
 * 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; version 2 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.
 *
 * For information on how to redistribute this software under
 * the terms of a license other than GNU General Public License
 * contact TMate Software at support@hg4j.com
 */
package org.tmatesoft.hg.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ReadableByteChannel;

import org.tmatesoft.hg.internal.StreamLogFacility;

/**
 *
 * @author Artem Tikhomirov
 * @author TMate Software Ltd.
 */
public class RegularFileInfo implements FileInfo {
	private File file;
	
	public RegularFileInfo() {
	}
	
	public void init(File f) {
		file = f;
	}
	
	public boolean exists() {
		return file.canRead() && file.isFile();
	}

	public int lastModified() {
		return (int) (file.lastModified() / 1000);
	}

	public long length() {
		return file.length();
	}

	public ReadableByteChannel newInputChannel() {
		try {
			return new FileInputStream(file).getChannel();
		} catch (FileNotFoundException ex) {
			StreamLogFacility.newDefault().debug(getClass(), ex, null);
			// shall not happen, provided this class is used correctly
			return new ReadableByteChannel() {
				
				public boolean isOpen() {
					return true;
				}
				
				public void close() throws IOException {
				}
				
				public int read(ByteBuffer dst) throws IOException {
					// EOF right away
					return -1;
				}
			};
		}
	}

}