org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Show.java - jgit - Git at Google

 /*
  * Copyright (C) 2010, Google Inc.
  * Copyright (C) 2006-2008, Robin Rosenberg <robin.rosenberg@dewire.com>
  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
  * under the terms of the Eclipse Distribution License v1.0 which
  * accompanies this distribution, is reproduced below, and is
  * available at http://www.eclipse.org/org/documents/edl-v10.php
  *
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or
  * without modification, are permitted provided that the following
  * conditions are met:
  *
  * - Redistributions of source code must retain the above copyright
  *   notice, this list of conditions and the following disclaimer.
  *
  * - Redistributions in binary form must reproduce the above
  *   copyright notice, this list of conditions and the following
  *   disclaimer in the documentation and/or other materials provided
  *   with the distribution.
  *
  * - Neither the name of the Eclipse Foundation, Inc. nor the
  *   names of its contributors may be used to endorse or promote
  *   products derived from this software without specific prior
  *   written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 package org.eclipse.jgit.pgm;

 import java.io.BufferedOutputStream;
 import java.io.IOException;
 import java.text.DateFormat;
 import java.text.MessageFormat;
 import java.text.SimpleDateFormat;
 import java.util.Locale;
 import java.util.TimeZone;

 import org.eclipse.jgit.diff.DiffFormatter;
 import org.eclipse.jgit.diff.RawTextComparator;
 import org.eclipse.jgit.diff.RenameDetector;
 import org.eclipse.jgit.errors.CorruptObjectException;
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
 import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.errors.RevisionSyntaxException;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.pgm.internal.CLIText;
 import org.eclipse.jgit.pgm.opt.PathTreeFilterHandler;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevObject;
 import org.eclipse.jgit.revwalk.RevTag;
 import org.eclipse.jgit.revwalk.RevTree;
 import org.eclipse.jgit.revwalk.RevWalk;
 import org.eclipse.jgit.treewalk.TreeWalk;
 import org.eclipse.jgit.treewalk.filter.TreeFilter;
 import org.kohsuke.args4j.Argument;
 import org.kohsuke.args4j.Option;

 @Command(common = true, usage = "usage_show")
 class Show extends TextBuiltin {
 	private final TimeZone myTZ = TimeZone.getDefault();

 	private final DateFormat fmt;

 	private DiffFormatter diffFmt;

 	@Argument(index = 0, metaVar = "metaVar_object")
 	private String objectName;

 	@Option(name = "--", metaVar = "metaVar_path", handler = PathTreeFilterHandler.class)
 	protected TreeFilter pathFilter = TreeFilter.ALL;

 	// BEGIN -- Options shared with Diff
 	@Option(name = "-p", usage = "usage_showPatch")
 	boolean showPatch;

 	@Option(name = "-M", usage = "usage_detectRenames")
 	private Boolean detectRenames;

 	@Option(name = "--no-renames", usage = "usage_noRenames")
 	void noRenames(@SuppressWarnings("unused") boolean on) {
 		detectRenames = Boolean.FALSE;
 	}

 	@Option(name = "-l", usage = "usage_renameLimit")
 	private Integer renameLimit;

 	@Option(name = "--name-status", usage = "usage_nameStatus")
 	private boolean showNameAndStatusOnly;

 	@Option(name = "--ignore-space-at-eol")
 	void ignoreSpaceAtEol(@SuppressWarnings("unused") boolean on) {
 		diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_TRAILING);
 	}

 	@Option(name = "--ignore-leading-space")
 	void ignoreLeadingSpace(@SuppressWarnings("unused") boolean on) {
 		diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_LEADING);
 	}

 	@Option(name = "-b", aliases = { "--ignore-space-change" })
 	void ignoreSpaceChange(@SuppressWarnings("unused") boolean on) {
 		diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_CHANGE);
 	}

 	@Option(name = "-w", aliases = { "--ignore-all-space" })
 	void ignoreAllSpace(@SuppressWarnings("unused") boolean on) {
 		diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_ALL);
 	}

 	@Option(name = "-U", aliases = { "--unified" }, metaVar = "metaVar_linesOfContext")
 	void unified(int lines) {
 		diffFmt.setContext(lines);
 	}

 	@Option(name = "--abbrev", metaVar = "metaVar_n")
 	void abbrev(int lines) {
 		diffFmt.setAbbreviationLength(lines);
 	}

 	@Option(name = "--full-index")
 	void abbrev(@SuppressWarnings("unused") boolean on) {
 		diffFmt.setAbbreviationLength(Constants.OBJECT_ID_STRING_LENGTH);
 	}

 	@Option(name = "--src-prefix", usage = "usage_srcPrefix")
 	void sourcePrefix(String path) {
 		diffFmt.setOldPrefix(path);
 	}

 	@Option(name = "--dst-prefix", usage = "usage_dstPrefix")
 	void dstPrefix(String path) {
 		diffFmt.setNewPrefix(path);
 	}

 	@Option(name = "--no-prefix", usage = "usage_noPrefix")
 	void noPrefix(@SuppressWarnings("unused") boolean on) {
 		diffFmt.setOldPrefix(""); //$NON-NLS-1$
 		diffFmt.setNewPrefix(""); //$NON-NLS-1$
 	}

 	// END -- Options shared with Diff

 	Show() {
 		fmt = new SimpleDateFormat("EEE MMM dd HH:mm:ss yyyy ZZZZZ", Locale.US); //$NON-NLS-1$
 	}

 	/** {@inheritDoc} */
 	@Override
 	protected void init(Repository repository, String gitDir) {
 		super.init(repository, gitDir);
 		diffFmt = new DiffFormatter(new BufferedOutputStream(outs));
 	}

 	/** {@inheritDoc} */
 	@SuppressWarnings("boxing")
 	@Override
 	protected void run() {
 		diffFmt.setRepository(db);
 		try {
 			diffFmt.setPathFilter(pathFilter);
 			if (detectRenames != null) {
 				diffFmt.setDetectRenames(detectRenames.booleanValue());
 			}
 			if (renameLimit != null && diffFmt.isDetectRenames()) {
 				RenameDetector rd = diffFmt.getRenameDetector();
 				rd.setRenameLimit(renameLimit.intValue());
 			}

 			ObjectId objectId;
 			if (objectName == null) {
 				objectId = db.resolve(Constants.HEAD);
 			} else {
 				objectId = db.resolve(objectName);
 			}

 			try (RevWalk rw = new RevWalk(db)) {
 				RevObject obj = rw.parseAny(objectId);
 				while (obj instanceof RevTag) {
 					show((RevTag) obj);
 					obj = ((RevTag) obj).getObject();
 					rw.parseBody(obj);
 				}

 				switch (obj.getType()) {
 				case Constants.OBJ_COMMIT:
 					show(rw, (RevCommit) obj);
 					break;

 				case Constants.OBJ_TREE:
 					outw.print("tree "); //$NON-NLS-1$
 					outw.print(objectName);
 					outw.println();
 					outw.println();
 					show((RevTree) obj);
 					break;

 				case Constants.OBJ_BLOB:
 					db.open(obj, obj.getType()).copyTo(System.out);
 					outw.flush();
 					break;

 				default:
 					throw die(MessageFormat.format(
 							CLIText.get().cannotReadBecause, obj.name(),
 							obj.getType()));
 				}
 			}
 		} catch (RevisionSyntaxException | IOException e) {
 			throw die(e.getMessage(), e);
 		} finally {
 			diffFmt.close();
 		}
 	}

 	private void show(RevTag tag) throws IOException {
 		outw.print(CLIText.get().tagLabel);
 		outw.print(" "); //$NON-NLS-1$
 		outw.print(tag.getTagName());
 		outw.println();

 		final PersonIdent tagger = tag.getTaggerIdent();
 		if (tagger != null) {
 			outw.println(MessageFormat.format(CLIText.get().taggerInfo,
 					tagger.getName(), tagger.getEmailAddress()));

 			final TimeZone taggerTZ = tagger.getTimeZone();
 			fmt.setTimeZone(taggerTZ != null ? taggerTZ : myTZ);
 			outw.println(MessageFormat.format(CLIText.get().dateInfo,
 					fmt.format(tagger.getWhen())));
 		}

 		outw.println();
 		final String[] lines = tag.getFullMessage().split("\n"); //$NON-NLS-1$
 		for (String s : lines) {
 			outw.print("    "); //$NON-NLS-1$
 			outw.print(s);
 			outw.println();
 		}

 		outw.println();
 	}

 	private void show(RevTree obj) throws MissingObjectException,
 			IncorrectObjectTypeException, CorruptObjectException, IOException {
 		try (TreeWalk walk = new TreeWalk(db)) {
 			walk.reset();
 			walk.addTree(obj);

 			while (walk.next()) {
 				outw.print(walk.getPathString());
 				final FileMode mode = walk.getFileMode(0);
 				if (mode == FileMode.TREE)
 					outw.print("/"); //$NON-NLS-1$
 				outw.println();
 			}
 		}
 	}

 	private void show(RevWalk rw, RevCommit c) throws IOException {
 		char[] outbuffer = new char[Constants.OBJECT_ID_LENGTH * 2];

 		outw.print(CLIText.get().commitLabel);
 		outw.print(" "); //$NON-NLS-1$
 		c.getId().copyTo(outbuffer, outw);
 		outw.println();

 		final PersonIdent author = c.getAuthorIdent();
 		outw.println(MessageFormat.format(CLIText.get().authorInfo,
 				author.getName(), author.getEmailAddress()));

 		final TimeZone authorTZ = author.getTimeZone();
 		fmt.setTimeZone(authorTZ != null ? authorTZ : myTZ);
 		outw.println(MessageFormat.format(CLIText.get().dateInfo,
 				fmt.format(author.getWhen())));

 		outw.println();
 		final String[] lines = c.getFullMessage().split("\n"); //$NON-NLS-1$
 		for (String s : lines) {
 			outw.print("    "); //$NON-NLS-1$
 			outw.print(s);
 			outw.println();
 		}

 		outw.println();
 		if (c.getParentCount() == 1) {
 			rw.parseHeaders(c.getParent(0));
 			showDiff(c);
 		}
 		outw.flush();
 	}

 	private void showDiff(RevCommit c) throws IOException {
 		final RevTree a = c.getParent(0).getTree();
 		final RevTree b = c.getTree();

 		if (showNameAndStatusOnly)
 			Diff.nameStatus(outw, diffFmt.scan(a, b));
 		else {
 			outw.flush();
 			diffFmt.format(a, b);
 			diffFmt.flush();
 		}
 		outw.println();
 	}
 }
	/*
	* Copyright (C) 2010, Google Inc.
	* Copyright (C) 2006-2008, Robin Rosenberg <robin.rosenberg@dewire.com>
	* Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
	* and other copyright owners as documented in the project's IP log.
	*
	* This program and the accompanying materials are made available
	* under the terms of the Eclipse Distribution License v1.0 which
	* accompanies this distribution, is reproduced below, and is
	* available at http://www.eclipse.org/org/documents/edl-v10.php
	*
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials provided
	* with the distribution.
	*
	* - Neither the name of the Eclipse Foundation, Inc. nor the
	* names of its contributors may be used to endorse or promote
	* products derived from this software without specific prior
	* written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
	* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
	* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
	* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
	* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	package org.eclipse.jgit.pgm;

	import java.io.BufferedOutputStream;
	import java.io.IOException;
	import java.text.DateFormat;
	import java.text.MessageFormat;
	import java.text.SimpleDateFormat;
	import java.util.Locale;
	import java.util.TimeZone;

	import org.eclipse.jgit.diff.DiffFormatter;
	import org.eclipse.jgit.diff.RawTextComparator;
	import org.eclipse.jgit.diff.RenameDetector;
	import org.eclipse.jgit.errors.CorruptObjectException;
	import org.eclipse.jgit.errors.IncorrectObjectTypeException;
	import org.eclipse.jgit.errors.MissingObjectException;
	import org.eclipse.jgit.errors.RevisionSyntaxException;
	import org.eclipse.jgit.lib.Constants;
	import org.eclipse.jgit.lib.FileMode;
	import org.eclipse.jgit.lib.ObjectId;
	import org.eclipse.jgit.lib.PersonIdent;
	import org.eclipse.jgit.lib.Repository;
	import org.eclipse.jgit.pgm.internal.CLIText;
	import org.eclipse.jgit.pgm.opt.PathTreeFilterHandler;
	import org.eclipse.jgit.revwalk.RevCommit;
	import org.eclipse.jgit.revwalk.RevObject;
	import org.eclipse.jgit.revwalk.RevTag;
	import org.eclipse.jgit.revwalk.RevTree;
	import org.eclipse.jgit.revwalk.RevWalk;
	import org.eclipse.jgit.treewalk.TreeWalk;
	import org.eclipse.jgit.treewalk.filter.TreeFilter;
	import org.kohsuke.args4j.Argument;
	import org.kohsuke.args4j.Option;

	@Command(common = true, usage = "usage_show")
	class Show extends TextBuiltin {
	private final TimeZone myTZ = TimeZone.getDefault();

	private final DateFormat fmt;

	private DiffFormatter diffFmt;

	@Argument(index = 0, metaVar = "metaVar_object")
	private String objectName;

	@Option(name = "--", metaVar = "metaVar_path", handler = PathTreeFilterHandler.class)
	protected TreeFilter pathFilter = TreeFilter.ALL;

	// BEGIN -- Options shared with Diff
	@Option(name = "-p", usage = "usage_showPatch")
	boolean showPatch;

	@Option(name = "-M", usage = "usage_detectRenames")
	private Boolean detectRenames;

	@Option(name = "--no-renames", usage = "usage_noRenames")
	void noRenames(@SuppressWarnings("unused") boolean on) {
	detectRenames = Boolean.FALSE;
	}

	@Option(name = "-l", usage = "usage_renameLimit")
	private Integer renameLimit;

	@Option(name = "--name-status", usage = "usage_nameStatus")
	private boolean showNameAndStatusOnly;

	@Option(name = "--ignore-space-at-eol")
	void ignoreSpaceAtEol(@SuppressWarnings("unused") boolean on) {
	diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_TRAILING);
	}

	@Option(name = "--ignore-leading-space")
	void ignoreLeadingSpace(@SuppressWarnings("unused") boolean on) {
	diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_LEADING);
	}

	@Option(name = "-b", aliases = { "--ignore-space-change" })
	void ignoreSpaceChange(@SuppressWarnings("unused") boolean on) {
	diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_CHANGE);
	}

	@Option(name = "-w", aliases = { "--ignore-all-space" })
	void ignoreAllSpace(@SuppressWarnings("unused") boolean on) {
	diffFmt.setDiffComparator(RawTextComparator.WS_IGNORE_ALL);
	}

	@Option(name = "-U", aliases = { "--unified" }, metaVar = "metaVar_linesOfContext")
	void unified(int lines) {
	diffFmt.setContext(lines);
	}

	@Option(name = "--abbrev", metaVar = "metaVar_n")
	void abbrev(int lines) {
	diffFmt.setAbbreviationLength(lines);
	}

	@Option(name = "--full-index")
	void abbrev(@SuppressWarnings("unused") boolean on) {
	diffFmt.setAbbreviationLength(Constants.OBJECT_ID_STRING_LENGTH);
	}

	@Option(name = "--src-prefix", usage = "usage_srcPrefix")
	void sourcePrefix(String path) {
	diffFmt.setOldPrefix(path);
	}

	@Option(name = "--dst-prefix", usage = "usage_dstPrefix")
	void dstPrefix(String path) {
	diffFmt.setNewPrefix(path);
	}

	@Option(name = "--no-prefix", usage = "usage_noPrefix")
	void noPrefix(@SuppressWarnings("unused") boolean on) {
	diffFmt.setOldPrefix(""); //$NON-NLS-1$
	diffFmt.setNewPrefix(""); //$NON-NLS-1$
	}

	// END -- Options shared with Diff

	Show() {
	fmt = new SimpleDateFormat("EEE MMM dd HH:mm:ss yyyy ZZZZZ", Locale.US); //$NON-NLS-1$
	}

	/** {@inheritDoc} */
	@Override
	protected void init(Repository repository, String gitDir) {
	super.init(repository, gitDir);
	diffFmt = new DiffFormatter(new BufferedOutputStream(outs));
	}

	/** {@inheritDoc} */
	@SuppressWarnings("boxing")
	@Override
	protected void run() {
	diffFmt.setRepository(db);
	try {
	diffFmt.setPathFilter(pathFilter);
	if (detectRenames != null) {
	diffFmt.setDetectRenames(detectRenames.booleanValue());
	}
	if (renameLimit != null && diffFmt.isDetectRenames()) {
	RenameDetector rd = diffFmt.getRenameDetector();
	rd.setRenameLimit(renameLimit.intValue());
	}

	ObjectId objectId;
	if (objectName == null) {
	objectId = db.resolve(Constants.HEAD);
	} else {
	objectId = db.resolve(objectName);
	}

	try (RevWalk rw = new RevWalk(db)) {
	RevObject obj = rw.parseAny(objectId);
	while (obj instanceof RevTag) {
	show((RevTag) obj);
	obj = ((RevTag) obj).getObject();
	rw.parseBody(obj);
	}

	switch (obj.getType()) {
	case Constants.OBJ_COMMIT:
	show(rw, (RevCommit) obj);
	break;

	case Constants.OBJ_TREE:
	outw.print("tree "); //$NON-NLS-1$
	outw.print(objectName);
	outw.println();
	outw.println();
	show((RevTree) obj);
	break;

	case Constants.OBJ_BLOB:
	db.open(obj, obj.getType()).copyTo(System.out);
	outw.flush();
	break;

	default:
	throw die(MessageFormat.format(
	CLIText.get().cannotReadBecause, obj.name(),
	obj.getType()));
	}
	}
	} catch (RevisionSyntaxException \| IOException e) {
	throw die(e.getMessage(), e);
	} finally {
	diffFmt.close();
	}
	}

	private void show(RevTag tag) throws IOException {
	outw.print(CLIText.get().tagLabel);
	outw.print(" "); //$NON-NLS-1$
	outw.print(tag.getTagName());
	outw.println();

	final PersonIdent tagger = tag.getTaggerIdent();
	if (tagger != null) {
	outw.println(MessageFormat.format(CLIText.get().taggerInfo,
	tagger.getName(), tagger.getEmailAddress()));

	final TimeZone taggerTZ = tagger.getTimeZone();
	fmt.setTimeZone(taggerTZ != null ? taggerTZ : myTZ);
	outw.println(MessageFormat.format(CLIText.get().dateInfo,
	fmt.format(tagger.getWhen())));
	}

	outw.println();
	final String[] lines = tag.getFullMessage().split("\n"); //$NON-NLS-1$
	for (String s : lines) {
	outw.print(" "); //$NON-NLS-1$
	outw.print(s);
	outw.println();
	}

	outw.println();
	}

	private void show(RevTree obj) throws MissingObjectException,
	IncorrectObjectTypeException, CorruptObjectException, IOException {
	try (TreeWalk walk = new TreeWalk(db)) {
	walk.reset();
	walk.addTree(obj);

	while (walk.next()) {
	outw.print(walk.getPathString());
	final FileMode mode = walk.getFileMode(0);
	if (mode == FileMode.TREE)
	outw.print("/"); //$NON-NLS-1$
	outw.println();
	}
	}
	}

	private void show(RevWalk rw, RevCommit c) throws IOException {
	char[] outbuffer = new char[Constants.OBJECT_ID_LENGTH * 2];

	outw.print(CLIText.get().commitLabel);
	outw.print(" "); //$NON-NLS-1$
	c.getId().copyTo(outbuffer, outw);
	outw.println();

	final PersonIdent author = c.getAuthorIdent();
	outw.println(MessageFormat.format(CLIText.get().authorInfo,
	author.getName(), author.getEmailAddress()));

	final TimeZone authorTZ = author.getTimeZone();
	fmt.setTimeZone(authorTZ != null ? authorTZ : myTZ);
	outw.println(MessageFormat.format(CLIText.get().dateInfo,
	fmt.format(author.getWhen())));

	outw.println();
	final String[] lines = c.getFullMessage().split("\n"); //$NON-NLS-1$
	for (String s : lines) {
	outw.print(" "); //$NON-NLS-1$
	outw.print(s);
	outw.println();
	}

	outw.println();
	if (c.getParentCount() == 1) {
	rw.parseHeaders(c.getParent(0));
	showDiff(c);
	}
	outw.flush();
	}

	private void showDiff(RevCommit c) throws IOException {
	final RevTree a = c.getParent(0).getTree();
	final RevTree b = c.getTree();

	if (showNameAndStatusOnly)
	Diff.nameStatus(outw, diffFmt.scan(a, b));
	else {
	outw.flush();
	diffFmt.format(a, b);
	diffFmt.flush();
	}
	outw.println();
	}
	}