Java tutorial
/* * 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; } 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; } }