tikhomirov@480: /*
tikhomirov@480:  * Copyright (c) 2012 TMate Software Ltd
tikhomirov@480:  *  
tikhomirov@480:  * This program is free software; you can redistribute it and/or modify
tikhomirov@480:  * it under the terms of the GNU General Public License as published by
tikhomirov@480:  * the Free Software Foundation; version 2 of the License.
tikhomirov@480:  *
tikhomirov@480:  * This program is distributed in the hope that it will be useful,
tikhomirov@480:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
tikhomirov@480:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tikhomirov@480:  * GNU General Public License for more details.
tikhomirov@480:  *
tikhomirov@480:  * For information on how to redistribute this software under
tikhomirov@480:  * the terms of a license other than GNU General Public License
tikhomirov@480:  * contact TMate Software at support@hg4j.com
tikhomirov@480:  */
tikhomirov@480: package org.tmatesoft.hg.internal;
tikhomirov@480: 
tikhomirov@480: import static org.tmatesoft.hg.util.LogFacility.Severity.Warn;
tikhomirov@480: 
tikhomirov@480: import java.io.BufferedReader;
tikhomirov@480: import java.io.File;
tikhomirov@480: import java.io.FileReader;
tikhomirov@480: import java.io.IOException;
tikhomirov@480: import java.util.Collection;
tikhomirov@480: 
tikhomirov@480: import org.tmatesoft.hg.repo.HgInvalidFileException;
tikhomirov@480: import org.tmatesoft.hg.repo.ext.MqManager;
tikhomirov@480: import org.tmatesoft.hg.util.LogFacility;
tikhomirov@480: 
tikhomirov@480: /**
tikhomirov@480:  * Handy class to read line-based configuration files
tikhomirov@480:  * 
tikhomirov@480:  * @author Artem Tikhomirov
tikhomirov@480:  * @author TMate Software Ltd.
tikhomirov@480:  */
tikhomirov@480: public final class LineReader {
tikhomirov@480: 		
tikhomirov@480: 		public interface LineConsumer<T> {
tikhomirov@480: 	//		boolean begin(File f, T paramObj) throws IOException;
tikhomirov@480: 			boolean consume(String line, T paramObj) throws IOException;
tikhomirov@480: 	//		boolean end(File f, T paramObj) throws IOException;
tikhomirov@480: 		}
tikhomirov@480: 
tikhomirov@480: 		public static class SimpleLineCollector implements LineReader.LineConsumer<Collection<String>> {
tikhomirov@480: 		
tikhomirov@480: 			public boolean consume(String line, Collection<String> result) throws IOException {
tikhomirov@480: 				result.add(line);
tikhomirov@480: 				return true;
tikhomirov@480: 			}
tikhomirov@480: 		}
tikhomirov@480: 
tikhomirov@480: 		private final File file;
tikhomirov@480: 		private final LogFacility log;
tikhomirov@480: 		private boolean trimLines = true;
tikhomirov@480: 		private boolean skipEmpty = true;
tikhomirov@480: 		private String ignoreThatStarts = null;
tikhomirov@480: 
tikhomirov@480: 		public LineReader(File f, LogFacility logFacility) {
tikhomirov@480: 			file = f;
tikhomirov@480: 			log = logFacility;
tikhomirov@480: 		}
tikhomirov@480: 		
tikhomirov@480: 		/**
tikhomirov@480: 		 * default: <code>true</code>
tikhomirov@480: 		 * <code>false</code> to return line as is
tikhomirov@480: 		 */
tikhomirov@480: 		public LineReader trimLines(boolean trim) {
tikhomirov@480: 			trimLines = trim;
tikhomirov@480: 			return this;
tikhomirov@480: 		}
tikhomirov@480: 		
tikhomirov@480: 		/**
tikhomirov@480: 		 * default: <code>true</code>
tikhomirov@480: 		 * <code>false</code> to pass empty lines to consumer
tikhomirov@480: 		 */
tikhomirov@480: 		public LineReader skipEmpty(boolean skip) {
tikhomirov@480: 			skipEmpty = skip;
tikhomirov@480: 			return this;
tikhomirov@480: 		}
tikhomirov@480: 		
tikhomirov@480: 		/**
tikhomirov@480: 		 * default: doesn't skip any line.
tikhomirov@480: 		 * set e.g. to "#" or "//" to skip lines that start with such prefix
tikhomirov@480: 		 */
tikhomirov@480: 		public LineReader ignoreLineComments(String lineStart) {
tikhomirov@480: 			ignoreThatStarts = lineStart;
tikhomirov@480: 			return this;
tikhomirov@480: 		}
tikhomirov@480: 
tikhomirov@480: 		public <T> void read(LineConsumer<T> consumer, T paramObj) throws HgInvalidFileException {
tikhomirov@480: 			BufferedReader statusFileReader = null;
tikhomirov@480: 			try {
tikhomirov@480: //				consumer.begin(file, paramObj);
tikhomirov@480: 				statusFileReader = new BufferedReader(new FileReader(file));
tikhomirov@480: 				String line;
tikhomirov@480: 				boolean ok = true;
tikhomirov@480: 				while (ok && (line = statusFileReader.readLine()) != null) {
tikhomirov@480: 					if (trimLines) {
tikhomirov@480: 						line = line.trim();
tikhomirov@480: 					}
tikhomirov@480: 					if (ignoreThatStarts != null && line.startsWith(ignoreThatStarts)) {
tikhomirov@480: 						continue;
tikhomirov@480: 					}
tikhomirov@480: 					if (!skipEmpty || line.length() > 0) {
tikhomirov@480: 						ok = consumer.consume(line, paramObj);
tikhomirov@480: 					}
tikhomirov@480: 				}
tikhomirov@480: 			} catch (IOException ex) {
tikhomirov@480: 				throw new HgInvalidFileException(ex.getMessage(), ex, file);
tikhomirov@480: 			} finally {
tikhomirov@483: 				if (statusFileReader != null) {
tikhomirov@483: 					try {
tikhomirov@483: 						statusFileReader.close();
tikhomirov@483: 					} catch (IOException ex) {
tikhomirov@483: 						log.dump(MqManager.class, Warn, ex, null);
tikhomirov@483: 					}
tikhomirov@480: 				}
tikhomirov@480: //				try {
tikhomirov@480: //					consumer.end(file, paramObj);
tikhomirov@480: //				} catch (IOException ex) {
tikhomirov@480: //					log.warn(MqManager.class, ex, null);
tikhomirov@480: //				}
tikhomirov@480: 			}
tikhomirov@480: 		}
tikhomirov@480: 	}