Java 读取过滤文本文件的最快方法是什么

我试图循环浏览一个日志(log)文本文件，其中包含SSH登录和其他日志(log).

程序正在返回SSH登录的总数.

我的解决方案确实有效，但似乎有点慢(在200mo文件中约3.5秒).我想知道是否有任何方法可以让它更快.我对Java的良好实践并不十分熟悉.

我用的是BufferedReader级.也许有更好的课程/方法，但我在网上找到的其他东西都比较慢.

{
            BufferedReader br;
            if(fileLocation != null) {
                br = new BufferedReader(new FileReader(fileLocation));
            }
            else {
                br = new BufferedReader((new InputStreamReader(System.in, "UTF-8")));
            }
            String line;
            Stack<String> users = new Stack<>();
            int succeeded = 0;
            int failed;
            int total = 0;

            if(!br.ready()) {
                help("Cannot read the file", true);
            }
            while((line=br.readLine())!=null)
            {
                if(!line.contains("sshd")) continue;
                String[] arr = line.split("\\s+");
                if(arr.length < 11) continue;


                String log = arr[4];
                String log2 = arr[5];
                String log3 = arr[8];
                String user = arr[10];
                if(!log.contains("sshd")) continue;
                if(!log2.contains("Accepted")) {
                    if(log3.contains("failure")) {
                        total++;
                    }
                    continue;
                }
                total++;
                succeeded++;

                if(!repeat) {
                    if (users.contains(user)) continue;
                    users.add(user);
                }

                System.out.println((total + 1) + " " + user);
            }

完整代码:https://pastebin.com/xp2P9wja

此外，以下是日志(log)文件的几行:

Dec  3 12:20:12 k332 sshd[25206]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=10.147.222.137 
Dec  3 12:20:14 k332 sshd[25204]: error: PAM: Authentication failure for illegal user admin from 10.147.222.137
Dec  3 12:20:14 k332 sshd[25204]: Failed keyboard-interactive/pam for invalid user admin from 10.147.222.137 port 36417 ssh2
Dec  3 12:20:14 k332 sshd[25204]: Connection closed by invalid user admin 10.147.222.137 port 36417 [preauth]
Dec  3 12:20:40 k332 sshd[25209]: pam_tally2(sshd:auth): Tally overflowed for user root

最终输出为:

Total :
103 unique IP SSH logins succeeded
30387 SSH logins succeeded
17186 SSH logins failed
47573 total SSH logins

谢谢你抽出时间！

编辑:Mo(兆字节)=MB(兆字节)(我们通常在法语中说Mo)

以下是所有人都需要的完整更新代码:https://pastebin.com/Kn5EqLNX