import java.io.File;
import java.util.Iterator;
import org.apache.commons.io.FileUtils;
import org.eclipse.jgit.api.Git;
import org.eclipse.jgit.api.RevertCommand;
import org.eclipse.jgit.revwalk.RevCommit;

public class JGit1 {

    public static void main(String[] args) {
        try {
            // create a clean repository
            File path = new File("c:/temp/agit/gitrepo");
            if (path.exists()) {
                FileUtils.deleteDirectory(path);
            }
            Git git = Git.init().setDirectory(path).call();
            System.out.println("Created a new repository at " + git.getRepository().getDirectory());

            // Create a new file and add it to the index
            File newFile = new File(path, "file1.txt");
            FileUtils.writeStringToFile(newFile, "Line 1\r\n", "UTF-8", true);
            git.add().addFilepattern("file1.txt").call();
            RevCommit rev1 = git.commit().setAuthor("test", "test@test.com").setMessage("Commit Log 1").call();

            // commit some changes
            FileUtils.writeStringToFile(newFile, "Line 2\r\n", "UTF-8", true);
            git.add().addFilepattern("file1.txt").call();
            RevCommit rev2 = git.commit().setAuthor("test", "test@test.com").setMessage("Commit Log 2").call();

            // commit some changes
            FileUtils.writeStringToFile(newFile, "Line 3\r\n", "UTF-8", true);
            git.add().addFilepattern("file1.txt").call();
            RevCommit rev3 = git.commit().setAuthor("test", "test@test.com").setMessage("Commit Log 3").call();

            RevertCommand revertCommand = git.revert();
            // revert to revision 2
            revertCommand.include(rev2);
            RevCommit revCommit = revertCommand.call();


            //git.add().addFilepattern("file1.txt").call();
            RevCommit rev4 = git.commit().setAuthor("test", "test@test.com").setMessage("Commit Log 4").call();
            
            // print logs
            Iterable<RevCommit> gitLog = git.log().call();
            Iterator<RevCommit> it = gitLog.iterator();
            while (it.hasNext()) {
                RevCommit logMessage = it.next();
                System.out.println(logMessage.getName() + " - " + logMessage.getFullMessage());
            }

        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
}

Line 1
<<<<<<< master
Line 2
Line 3
=======
>>>>>>> 54e7037 Commit Log 2

Line 1
Line 2

git rm -r .
git checkout rev2 .  # Watch the trailing '.'
git commit -m rev5 ...