public Ref call()

in org.eclipse.jgit/src/org/eclipse/jgit/api/CheckoutCommand.java [171:312]
131 lines of code
28 McCabe index (conditional complexity)

	public Ref call() throws GitAPIException, RefAlreadyExistsException,
			RefNotFoundException, InvalidRefNameException,
			CheckoutConflictException {
		checkCallable();
		try {
			processOptions();
			if (checkoutAllPaths || !paths.isEmpty()) {
				checkoutPaths();
				status = new CheckoutResult(Status.OK, paths);
				setCallable(false);
				return null;
			}

			if (createBranch) {
				try (Git git = new Git(repo)) {
					CreateBranchCommand command = git.branchCreate();
					command.setName(name);
					if (startCommit != null)
						command.setStartPoint(startCommit);
					else
						command.setStartPoint(startPoint);
					if (upstreamMode != null)
						command.setUpstreamMode(upstreamMode);
					command.call();
				}
			}

			Ref headRef = repo.exactRef(Constants.HEAD);
			if (headRef == null) {
				// TODO Git CLI supports checkout from unborn branch, we should
				// also allow this
				throw new UnsupportedOperationException(
						JGitText.get().cannotCheckoutFromUnbornBranch);
			}
			String shortHeadRef = getShortBranchName(headRef);
			String refLogMessage = "checkout: moving from " + shortHeadRef; //$NON-NLS-1$
			ObjectId branch;
			if (orphan) {
				if (startPoint == null && startCommit == null) {
					Result r = repo.updateRef(Constants.HEAD).link(
							getBranchName());
					if (!EnumSet.of(Result.NEW, Result.FORCED).contains(r))
						throw new JGitInternalException(MessageFormat.format(
								JGitText.get().checkoutUnexpectedResult,
								r.name()));
					this.status = CheckoutResult.NOT_TRIED_RESULT;
					return repo.exactRef(Constants.HEAD);
				}
				branch = getStartPointObjectId();
			} else {
				branch = repo.resolve(name);
				if (branch == null)
					throw new RefNotFoundException(MessageFormat.format(
							JGitText.get().refNotResolved, name));
			}

			RevCommit headCommit = null;
			RevCommit newCommit = null;
			try (RevWalk revWalk = new RevWalk(repo)) {
				AnyObjectId headId = headRef.getObjectId();
				headCommit = headId == null ? null
						: revWalk.parseCommit(headId);
				newCommit = revWalk.parseCommit(branch);
			}
			RevTree headTree = headCommit == null ? null : headCommit.getTree();
			DirCacheCheckout dco;
			DirCache dc = repo.lockDirCache();
			try {
				dco = new DirCacheCheckout(repo, headTree, dc,
						newCommit.getTree());
				dco.setFailOnConflict(true);
				dco.setForce(forced);
				if (forced) {
					dco.setFailOnConflict(false);
				}
				dco.setProgressMonitor(monitor);
				try {
					dco.checkout();
				} catch (org.eclipse.jgit.errors.CheckoutConflictException e) {
					status = new CheckoutResult(Status.CONFLICTS,
							dco.getConflicts());
					throw new CheckoutConflictException(dco.getConflicts(), e);
				}
			} finally {
				dc.unlock();
			}
			Ref ref = repo.findRef(name);
			if (ref != null && !ref.getName().startsWith(Constants.R_HEADS))
				ref = null;
			String toName = Repository.shortenRefName(name);
			RefUpdate refUpdate = repo.updateRef(Constants.HEAD, ref == null);
			refUpdate.setForceUpdate(forceRefUpdate);
			refUpdate.setRefLogMessage(refLogMessage + " to " + toName, false); //$NON-NLS-1$
			Result updateResult;
			if (ref != null)
				updateResult = refUpdate.link(ref.getName());
			else if (orphan) {
				updateResult = refUpdate.link(getBranchName());
				ref = repo.exactRef(Constants.HEAD);
			} else {
				refUpdate.setNewObjectId(newCommit);
				updateResult = refUpdate.forceUpdate();
			}

			setCallable(false);

			boolean ok = false;
			switch (updateResult) {
			case NEW:
				ok = true;
				break;
			case NO_CHANGE:
			case FAST_FORWARD:
			case FORCED:
				ok = true;
				break;
			default:
				break;
			}

			if (!ok)
				throw new JGitInternalException(MessageFormat.format(JGitText
						.get().checkoutUnexpectedResult, updateResult.name()));


			if (!dco.getToBeDeleted().isEmpty()) {
				status = new CheckoutResult(Status.NONDELETED,
						dco.getToBeDeleted(),
						new ArrayList<>(dco.getUpdated().keySet()),
						dco.getRemoved());
			} else
				status = new CheckoutResult(new ArrayList<>(dco
						.getUpdated().keySet()), dco.getRemoved());

			return ref;
		} catch (IOException ioe) {
			throw new JGitInternalException(ioe.getMessage(), ioe);
		} finally {
			if (status == null)
				status = CheckoutResult.ERROR_RESULT;
		}
	}