How to properly parse email received headers?, Java

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//'main' method must be in a class 'Rextester'.
//openjdk version '11.0.5'

import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.LinkedList;
import java.util.HashMap;
import java.lang.StringBuilder;

class Rextester {
    public static void main(String[] args) {
        Pattern p = Pattern.compile("(?:(Received:)|\\G(?!\\A))" +
                                    "\\s*(from|by|with|id|via|for|;)" +
                                    "\\s*(\\S+?(?:\\s+\\S+?)*?)\\s*" +
                                    "(?=Received:|by|with|id|via|for|;|\\z)");
        String text = "Received: from VE1PR01MB5599.eurprd01.prod.exchangelabs.com\n" +
                      " (2603:10a6:7:7c::43) by HE1PR0102MB2714.eurprd01.prod.exchangelabs.com with\n" +
                      " HTTPS via HE1PR0402CA0054.EURPRD04.PROD.OUTLOOK.COM; Thu, 9 Jan 2020 16:34:13\n" +
                      " +0000\n" +
                      "\n" +
                      "Received: from VI1PR0102CA0029.eurprd01.prod.exchangelabs.com\n" +
                      " (2603:10a6:802::42) by VE1PR01MB5599.eurprd01.prod.exchangelabs.com\n" +
                      " (2603:10a6:803:11f::30) with Microsoft SMTP Server (version=TLS1_2,\n" +
                      " cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2602.12; Thu, 9 Jan\n" +
                      " 2020 16:34:13 +0000\n" +
                      "\n" +
                      "Received: from DB5EUR01FT034.eop-EUR01.prod.protection.outlook.com\n" +
                      " (2a01:111:f400:7e02::203) by VI1PR0102CA0029.outlook.office365.com\n" +
                      " (2603:10a6:802::42) with Microsoft SMTP Server (version=TLS1_2,\n" +
                      " cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2623.9 via Frontend\n" +
                      " Transport; Thu, 9 Jan 2020 16:34:13 +0000\n" +
                      "\n" +
                      "Received: from relay-out.ohc.cu (200.55.138.44) by\n" +
                      " DB5EUR01FT034.mail.protection.outlook.com (10.152.4.246) with Microsoft SMTP\n" +
                      " Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id\n" +
                      " 15.20.2623.9 via Frontend Transport; Thu, 9 Jan 2020 16:34:12 +0000\n" +
                      "\n" +
                      "Received: from relay-in.ohc.cu (relay-in.ohc.cu [127.0.0.1])\n" +
                      "    by relay-out.ohc.cu (Postfix) with ESMTP id 69EA722DD\n" +
                      "    for <some.email@some.domain>; Thu,  9 Jan 2020 11:29:43 -0500 (CST)\n" +
                      "\n" +
                      "Received: from relay-out.ohc.cu ([127.0.0.1])\n" +
                      "    by relay-in.ohc.cu (relay-in.ohc.cu [127.0.0.1]) (amavisd-new, port 10024)\n" +
                      "    with ESMTP id 7CZku5Y59vGC for <some.email@some.domain>;\n" +
                      "    Thu,  9 Jan 2020 11:29:38 -0500 (CST)\n" +
                      "\n" +
                      "Received: from correo.patrimonio.ohc.cu (unknown [192.168.229.20])\n" +
                      "    by relay-out.ohc.cu (Postfix) with ESMTP id B83BA22F5\n" +
                      "    for <some.email@some.domain>; Thu,  9 Jan 2020 11:29:36 -0500 (CST)\n" +
                      "\n" +
                      "Received: from localhost (localhost.localdomain [127.0.0.1])\n" +
                      "    by correo.patrimonio.ohc.cu (Postfix) with ESMTP id 65413232A001\n" +
                      "    for <some.email@some.domain>; Thu,  9 Jan 2020 11:40:05 -0500 (CST)\n" +
                      "\n" +
                      "Received: from correo.patrimonio.ohc.cu ([127.0.0.1])\n" +
                      "    by localhost (correo.patrimonio.ohc.cu [127.0.0.1]) (amavisd-new, port 10024)\n" +
                      "    with ESMTP id hNMp-6lHHtzH for <some.email@some.domain>;\n" +
                      "    Thu,  9 Jan 2020 11:40:05 -0500 (CST)\n" +
                      "\n" +
                      "Received: from correoweb.patrimonio.ohc.cu (unknown [192.168.229.23])\n" +
                      "    by correo.patrimonio.ohc.cu (Postfix) with ESMTPA id EC62A232A00A;\n" +
                      "    Thu,  9 Jan 2020 11:39:53 -0500 (CST)";
        LinkedList<HashMap<String, String>> data = new LinkedList<HashMap<String, String>>();
        HashMap<String, String> e;
        StringBuilder sb = new StringBuilder(4096);
        Matcher m = p.matcher(text);
        while (m.find()) {
            if (m.group(1) != null) {
                data.add(new HashMap<String, String>());
            }
            e = data.getLast();
            e.put(m.group(2), m.group(3));
        }
        sb.append("[");
        data.stream().forEach((x) -> sb.append(x).append(",\n"));
        if (sb.length() > 2) {
            sb.setLength(sb.length() - 2);
        }
        sb.append("]");
        System.out.println(sb);
    }
}

[ + ] Show input
Compilation time: 1.96 sec, absolute running time: 0.28 sec, cpu time: 0.21 sec, memory peak: 35 Mb, absolute service time: 2,33 sec