protected void undoCheckOut() {
		if (!checkRepositoryConnected()) {
			return;
		}

		closeEditorsForUndoCheckOut();

		List<Archive> archiveList = archiveProvider.getArchives();
		List<DomainFileArchive> unmodifiedCheckOutsList = new ArrayList<>();
		List<DomainFileArchive> modifiedCheckOutsList = new ArrayList<>();
		for (Archive archive2 : archiveList) {
			ProjectArchive archive = (ProjectArchive) archive2;
			DomainFile domainFile = archive.getDomainFile();
			if (domainFile.isCheckedOut()) {
				if (domainFile.modifiedSinceCheckout() || domainFile.isChanged()) {
					modifiedCheckOutsList.add(archive);
				}
				else {
					unmodifiedCheckOutsList.add(archive);
				}
			}
		}

		try {
			undoCheckOuts(unmodifiedCheckOutsList, modifiedCheckOutsList);
		}
		catch (CancelledException e) {
			tool.setStatusInfo("Undo checkouts was canceled");
			return;
		}
	}
Gets the domain files from the provider and then undoes the checkout on any that are 
checked out.
Ghidra/Features/Base/src/main/java/ghidra/framework/main/datatree/VersionControlDataTypeArchiveUndoCheckoutAction.java