org.eclipse.egit.ui.internal.actions.CompareWithHeadActionHandler.java Source code

Introduction

Here is the source code for org.eclipse.egit.ui.internal.actions.CompareWithHeadActionHandler.java

Source

/*******************************************************************************
 * Copyright (C) 2009, Stefan Lay <stefan.lay@sap.com>
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *******************************************************************************/
package org.eclipse.egit.ui.internal.actions;

import java.io.IOException;

import org.eclipse.compare.CompareUI;
import org.eclipse.compare.ITypedElement;
import org.eclipse.core.commands.ExecutionEvent;
import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;
import org.eclipse.egit.core.project.RepositoryMapping;
import org.eclipse.egit.ui.Activator;
import org.eclipse.egit.ui.internal.CompareUtils;
import org.eclipse.egit.ui.internal.GitCompareFileRevisionEditorInput;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.team.ui.synchronize.SaveableCompareEditorInput;

/**
 * Compares the working tree content of a file with the version of the file in
 * the HEAD commit.
 */
public class CompareWithHeadActionHandler extends RepositoryActionHandler {

    public Object execute(ExecutionEvent event) throws ExecutionException {
        final IResource resource = getSelectedResources(event)[0];
        final RepositoryMapping mapping = RepositoryMapping.getMapping(resource.getProject());
        final Repository repository = mapping.getRepository();
        final String gitPath = mapping.getRepoRelativePath(resource);

        final IFile baseFile = (IFile) resource;
        final ITypedElement base = SaveableCompareEditorInput.createFileElement(baseFile);

        ITypedElement next;
        try {
            Ref head = repository.getRef(Constants.HEAD);
            RevWalk rw = new RevWalk(repository);
            RevCommit commit = rw.parseCommit(head.getObjectId());

            next = CompareUtils.getFileRevisionTypedElement(gitPath, commit, repository);
        } catch (IOException e) {
            Activator.handleError(e.getMessage(), e, true);
            return null;
        }

        final GitCompareFileRevisionEditorInput in = new GitCompareFileRevisionEditorInput(base, next, null);
        CompareUI.openCompareEditor(in);
        return null;
    }

    @Override
    public boolean isEnabled() {
        final IResource[] selectedResources = getSelectedResources();
        if (selectedResources.length != 1)
            return false;

        final IResource resource = selectedResources[0];
        if (!(resource instanceof IFile)) {
            return false;
        }
        final RepositoryMapping mapping = RepositoryMapping.getMapping(resource.getProject());
        return mapping != null;
    }

}