this.target = target;
this.workTree = workTree;
this.progressListener = progressListener;
this.latestChangeset = 0;
this.latestTimestamp = 0;
this.pointCache = new BDBJEPointCache(platform);
Optional<NodeRef> waysNodeRef = cmdLocator.command(FindTreeChild.class)
.setChildPath(OSMUtils.WAY_TYPE_NAME).setParent(workTree.getTree()).call();
Optional<NodeRef> nodesNodeRef = cmdLocator.command(FindTreeChild.class)
.setChildPath(OSMUtils.NODE_TYPE_NAME).setParent(workTree.getTree()).call();
checkArgument(waysNodeRef.isPresent() || nodesNodeRef.isPresent(),