Mercurial > jhg
view src/org/tmatesoft/hg/internal/LineReader.java @ 686:f1f095e42555
Annotated file is not always changed in the latest changeset, need to find out last changest it was changed at (iow, diffed to with BlameHelper)
author | Artem Tikhomirov <tikhomirov.artem@gmail.com> |
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date | Thu, 25 Jul 2013 22:12:14 +0200 (2013-07-25) |
parents | 12a4f60ea972 |
children |
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/* * Copyright (c) 2012-2013 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.internal; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.FileReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.Reader; import java.nio.charset.Charset; import java.util.Collection; import org.tmatesoft.hg.core.HgIOException; import org.tmatesoft.hg.util.LogFacility; /** * Handy class to read line-based configuration files * * @author Artem Tikhomirov * @author TMate Software Ltd. */ public final class LineReader { public interface LineConsumer<T> { // boolean begin(File f, T paramObj) throws IOException; boolean consume(String line, T paramObj) throws IOException; // boolean end(File f, T paramObj) throws IOException; } public static class SimpleLineCollector implements LineReader.LineConsumer<Collection<String>> { public boolean consume(String line, Collection<String> result) throws IOException { result.add(line); return true; } } private final File file; private final LogFacility log; private final Charset encoding; private boolean trimLines = true; private boolean skipEmpty = true; private String ignoreThatStarts = null; public LineReader(File f, LogFacility logFacility) { this(f, logFacility, null); } public LineReader(File f, LogFacility logFacility, Charset lineEncoding) { file = f; log = logFacility; encoding = lineEncoding; } /** * default: <code>true</code> * <code>false</code> to return line as is */ public LineReader trimLines(boolean trim) { trimLines = trim; return this; } /** * default: <code>true</code> * <code>false</code> to pass empty lines to consumer */ public LineReader skipEmpty(boolean skip) { skipEmpty = skip; return this; } /** * default: doesn't skip any line. * set e.g. to "#" or "//" to skip lines that start with such prefix */ public LineReader ignoreLineComments(String lineStart) { ignoreThatStarts = lineStart; return this; } /** * * @param consumer where to pipe read lines to * @param paramObj parameterizes consumer * @return paramObj value for convenience * @throws HgIOException if there's {@link IOException} while reading file */ public <T> T read(LineConsumer<T> consumer, T paramObj) throws HgIOException { BufferedReader statusFileReader = null; try { // consumer.begin(file, paramObj); Reader fileReader; if (encoding == null) { fileReader = new FileReader(file); } else { fileReader = new InputStreamReader(new FileInputStream(file), encoding); } statusFileReader = new BufferedReader(fileReader); String line; boolean ok = true; while (ok && (line = statusFileReader.readLine()) != null) { if (trimLines) { line = line.trim(); } if (ignoreThatStarts != null && line.startsWith(ignoreThatStarts)) { continue; } if (!skipEmpty || line.length() > 0) { ok = consumer.consume(line, paramObj); } } return paramObj; } catch (IOException ex) { throw new HgIOException(ex.getMessage(), ex, file); } finally { new FileUtils(log, this).closeQuietly(statusFileReader); // try { // consumer.end(file, paramObj); // } catch (IOException ex) { // log.warn(getClass(), ex, null); // } } } }