DiffCommand.java
/*
* Copyright (C) 2011, Tomasz Zarna <Tomasz.Zarna@pl.ibm.com>
* 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.api;
import static org.eclipse.jgit.lib.Constants.HEAD;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.List;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.api.errors.JGitInternalException;
import org.eclipse.jgit.api.errors.NoHeadException;
import org.eclipse.jgit.diff.DiffEntry;
import org.eclipse.jgit.diff.DiffFormatter;
import org.eclipse.jgit.dircache.DirCacheIterator;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.NullProgressMonitor;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectReader;
import org.eclipse.jgit.lib.ProgressMonitor;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.treewalk.AbstractTreeIterator;
import org.eclipse.jgit.treewalk.CanonicalTreeParser;
import org.eclipse.jgit.treewalk.FileTreeIterator;
import org.eclipse.jgit.treewalk.filter.TreeFilter;
import org.eclipse.jgit.util.io.NullOutputStream;
/**
* Show changes between commits, commit and working tree, etc.
*
* @see <a href="http://www.kernel.org/pub/software/scm/git/docs/git-diff.html"
* >Git documentation about diff</a>
*/
public class DiffCommand extends GitCommand<List<DiffEntry>> {
private AbstractTreeIterator oldTree;
private AbstractTreeIterator newTree;
private boolean cached;
private TreeFilter pathFilter = TreeFilter.ALL;
private boolean showNameAndStatusOnly;
private OutputStream out;
private int contextLines = -1;
private String sourcePrefix;
private String destinationPrefix;
private ProgressMonitor monitor = NullProgressMonitor.INSTANCE;
/**
* Constructor for DiffCommand
*
* @param repo
* a {@link org.eclipse.jgit.lib.Repository} object.
*/
protected DiffCommand(Repository repo) {
super(repo);
}
private DiffFormatter getDiffFormatter() {
return out != null && !showNameAndStatusOnly
? new DiffFormatter(new BufferedOutputStream(out))
: new DiffFormatter(NullOutputStream.INSTANCE);
}
/**
* {@inheritDoc}
* <p>
* Executes the {@code Diff} command with all the options and parameters
* collected by the setter methods (e.g. {@link #setCached(boolean)} of this
* class. Each instance of this class should only be used for one invocation
* of the command. Don't call this method twice on an instance.
*/
@Override
public List<DiffEntry> call() throws GitAPIException {
try (DiffFormatter diffFmt = getDiffFormatter()) {
diffFmt.setRepository(repo);
diffFmt.setProgressMonitor(monitor);
if (cached) {
if (oldTree == null) {
ObjectId head = repo.resolve(HEAD + "^{tree}"); //$NON-NLS-1$
if (head == null)
throw new NoHeadException(JGitText.get().cannotReadTree);
CanonicalTreeParser p = new CanonicalTreeParser();
try (ObjectReader reader = repo.newObjectReader()) {
p.reset(reader, head);
}
oldTree = p;
}
newTree = new DirCacheIterator(repo.readDirCache());
} else {
if (oldTree == null)
oldTree = new DirCacheIterator(repo.readDirCache());
if (newTree == null)
newTree = new FileTreeIterator(repo);
}
diffFmt.setPathFilter(pathFilter);
List<DiffEntry> result = diffFmt.scan(oldTree, newTree);
if (showNameAndStatusOnly)
return result;
else {
if (contextLines >= 0)
diffFmt.setContext(contextLines);
if (destinationPrefix != null)
diffFmt.setNewPrefix(destinationPrefix);
if (sourcePrefix != null)
diffFmt.setOldPrefix(sourcePrefix);
diffFmt.format(result);
diffFmt.flush();
return result;
}
} catch (IOException e) {
throw new JGitInternalException(e.getMessage(), e);
}
}
/**
* Whether to view the changes staged for the next commit
*
* @param cached
* whether to view the changes staged for the next commit
* @return this instance
*/
public DiffCommand setCached(boolean cached) {
this.cached = cached;
return this;
}
/**
* Set path filter
*
* @param pathFilter
* parameter, used to limit the diff to the named path
* @return this instance
*/
public DiffCommand setPathFilter(TreeFilter pathFilter) {
this.pathFilter = pathFilter;
return this;
}
/**
* Set old tree
*
* @param oldTree
* the previous state
* @return this instance
*/
public DiffCommand setOldTree(AbstractTreeIterator oldTree) {
this.oldTree = oldTree;
return this;
}
/**
* Set new tree
*
* @param newTree
* the updated state
* @return this instance
*/
public DiffCommand setNewTree(AbstractTreeIterator newTree) {
this.newTree = newTree;
return this;
}
/**
* Set whether to return only names and status of changed files
*
* @param showNameAndStatusOnly
* whether to return only names and status of changed files
* @return this instance
*/
public DiffCommand setShowNameAndStatusOnly(boolean showNameAndStatusOnly) {
this.showNameAndStatusOnly = showNameAndStatusOnly;
return this;
}
/**
* Set output stream
*
* @param out
* the stream to write line data
* @return this instance
*/
public DiffCommand setOutputStream(OutputStream out) {
this.out = out;
return this;
}
/**
* Set number of context lines instead of the usual three.
*
* @param contextLines
* the number of context lines
* @return this instance
*/
public DiffCommand setContextLines(int contextLines) {
this.contextLines = contextLines;
return this;
}
/**
* Set the given source prefix instead of "a/".
*
* @param sourcePrefix
* the prefix
* @return this instance
*/
public DiffCommand setSourcePrefix(String sourcePrefix) {
this.sourcePrefix = sourcePrefix;
return this;
}
/**
* Set the given destination prefix instead of "b/".
*
* @param destinationPrefix
* the prefix
* @return this instance
*/
public DiffCommand setDestinationPrefix(String destinationPrefix) {
this.destinationPrefix = destinationPrefix;
return this;
}
/**
* The progress monitor associated with the diff operation. By default, this
* is set to <code>NullProgressMonitor</code>
*
* @see NullProgressMonitor
* @param monitor
* a progress monitor
* @return this instance
*/
public DiffCommand setProgressMonitor(ProgressMonitor monitor) {
if (monitor == null) {
monitor = NullProgressMonitor.INSTANCE;
}
this.monitor = monitor;
return this;
}
}