Method groupByServer

ZezeJava/ZezeJava/src/main/java/Zeze/Arch/Online.java:1370–1398

(@NotNull Collection<BLoginKey> accounts)

	}

	public @NotNull IntHashMap<RoleOnServer> groupByServer(@NotNull Collection<BLoginKey> accounts) {
		var groups = new IntHashMap<RoleOnServer>();
		var groupNotOnline = new RoleOnServer(); // LinkName is Empty And Socket is null.
		groups.put(groupNotOnline.serverId, groupNotOnline);

		for (var account : accounts) {
			var online = getOnline(account.getAccount());
			if (online == null || online.getLogins().isEmpty()) {
				// null != online 意味着这里肯定不为0，不会到达这个分支。
				// 下面要求Logins.Count必须大于0，判断一下吧。
				groupNotOnline.accounts.add(account);
				continue;
			}
			var login = online.getLogins().get(account.getClientId());
			if (null == login) {
				groupNotOnline.accounts.add(account);
				continue;
			}
			var serverId = login.getServerId();
			// 后面保存connector.Socket并使用，如果之后连接被关闭，以后发送协议失败。
			var group = groups.get(serverId);
			if (group == null) {
				group = new RoleOnServer(serverId);
				groups.put(serverId, group);
			}
			group.accounts.add(account);
		}
		return groups;
	}

	private static @NotNull RoleOnServer merge(@Nullable RoleOnServer current, @NotNull RoleOnServer m) {
		if (current == null)