tikhomirov@591: /*
tikhomirov@591:  * Copyright (c) 2013 TMate Software Ltd
tikhomirov@591:  *  
tikhomirov@591:  * This program is free software; you can redistribute it and/or modify
tikhomirov@591:  * it under the terms of the GNU General Public License as published by
tikhomirov@591:  * the Free Software Foundation; version 2 of the License.
tikhomirov@591:  *
tikhomirov@591:  * This program is distributed in the hope that it will be useful,
tikhomirov@591:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
tikhomirov@591:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tikhomirov@591:  * GNU General Public License for more details.
tikhomirov@591:  *
tikhomirov@591:  * For information on how to redistribute this software under
tikhomirov@591:  * the terms of a license other than GNU General Public License
tikhomirov@591:  * contact TMate Software at support@hg4j.com
tikhomirov@591:  */
tikhomirov@591: package org.tmatesoft.hg.internal;
tikhomirov@591: 
tikhomirov@591: import java.io.File;
tikhomirov@591: import java.io.IOException;
tikhomirov@591: import java.lang.ref.SoftReference;
tikhomirov@591: import java.util.HashMap;
tikhomirov@591: 
tikhomirov@591: import org.tmatesoft.hg.repo.HgInvalidControlFileException;
tikhomirov@591: import org.tmatesoft.hg.util.Path;
tikhomirov@591: 
tikhomirov@591: /**
tikhomirov@591:  * Factory to create {@link RevlogStream RevlogStreams}, cache-capable.
tikhomirov@591:  *   
tikhomirov@591:  * @author Artem Tikhomirov
tikhomirov@591:  * @author TMate Software Ltd.
tikhomirov@591:  */
tikhomirov@591: public final class RevlogStreamFactory {
tikhomirov@591: 	
tikhomirov@591: 	private final Internals repo;
tikhomirov@591: 	private final HashMap<Path, SoftReference<RevlogStream>> streamsCache;
tikhomirov@591: 
tikhomirov@591: 
tikhomirov@591: 	public RevlogStreamFactory(Internals hgRepo, boolean shallCacheRevlogs) {
tikhomirov@591: 		repo = hgRepo;
tikhomirov@591: 		if (shallCacheRevlogs) {
tikhomirov@591: 			streamsCache = new HashMap<Path, SoftReference<RevlogStream>>();
tikhomirov@591: 		} else {
tikhomirov@591: 			streamsCache = null;
tikhomirov@591: 		}
tikhomirov@591: 	}
tikhomirov@591: 	
tikhomirov@591: 	/**
tikhomirov@591: 	 * Creates a stream for specified file, doesn't cache stream
tikhomirov@591: 	 */
tikhomirov@591: 	/*package-local*/ RevlogStream create(File f) {
tikhomirov@591: 		return new RevlogStream(repo.getDataAccess(), f);
tikhomirov@591: 	}
tikhomirov@591: 
tikhomirov@591: 	/**
tikhomirov@591: 	 * Perhaps, should be separate interface, like ContentLookup
tikhomirov@591: 	 * @param path - normalized file name
tikhomirov@591: 	 * @return <code>null</code> if path doesn't resolve to a existing file
tikhomirov@591: 	 */
tikhomirov@591: 	/*package-local*/ RevlogStream resolveStoreFile(Path path) {
tikhomirov@591: 		final SoftReference<RevlogStream> ref = shallCacheRevlogs() ? streamsCache.get(path) : null;
tikhomirov@591: 		RevlogStream cached = ref == null ? null : ref.get();
tikhomirov@591: 		if (cached != null) {
tikhomirov@591: 			return cached;
tikhomirov@591: 		}
tikhomirov@591: 		File f = repo.getFileFromDataDir(path);
tikhomirov@591: 		if (f.exists()) {
tikhomirov@591: 			RevlogStream s = create(f);
tikhomirov@591: 			if (shallCacheRevlogs()) {
tikhomirov@591: 				streamsCache.put(path, new SoftReference<RevlogStream>(s));
tikhomirov@591: 			}
tikhomirov@591: 			return s;
tikhomirov@591: 		}
tikhomirov@591: 		return null;
tikhomirov@591: 	}
tikhomirov@591: 	
tikhomirov@591: 	/*package-local*/ RevlogStream createStoreFile(Path path) throws HgInvalidControlFileException {
tikhomirov@591: 		File f = repo.getFileFromDataDir(path);
tikhomirov@591: 		try {
tikhomirov@591: 			if (!f.exists()) {
tikhomirov@591: 				f.getParentFile().mkdirs();
tikhomirov@591: 				f.createNewFile();
tikhomirov@591: 			}
tikhomirov@591: 			RevlogStream s = create(f);
tikhomirov@591: 			if (shallCacheRevlogs()) {
tikhomirov@591: 				streamsCache.put(path, new SoftReference<RevlogStream>(s));
tikhomirov@591: 			}
tikhomirov@591: 			return s;
tikhomirov@591: 		} catch (IOException ex) {
tikhomirov@591: 			throw new HgInvalidControlFileException("Can't create a file in the storage", ex, f);
tikhomirov@591: 		}
tikhomirov@591: 	}
tikhomirov@591: 
tikhomirov@591: 	private boolean shallCacheRevlogs() {
tikhomirov@591: 		return streamsCache != null;
tikhomirov@591: 	}
tikhomirov@591: }