使用 Java StAX 解析 XML - 计算内容标签的数量

Question

我有很大的 XML 文件，我正在解析如下：

public class Solution {

    private static final String ROOM_ID = "RoomID";
    private static final String CONTENT = "Content";
    private static final String LOGIN_NAME = "LoginName";
    private static final String CONVERSATION_ID = "ConversationID";
    private static final String FILE_DUMP = "FileDump";
    private static final String MESSAGE = "Message";
    private static final String CONVERSATION = "Conversation";
    private static final String START_TIME = "StartTime";

    static class ConversationInfo {

        private String startTimeStr;
        private String conversationId;
        private String fileName;
        private int orderInFile;
        private final Set<String> users = new HashSet<>();
        private final List<Message> messages = new ArrayList<>();
        public HashMap<String, String> map = new HashMap<>();

        @Override
        public String toString() {
            return String.format("%s %d %s %s %s %d  %s", fileName, orderInFile, conversationId,
                    startTimeStr, StringUtils.join(users, "***"), users.size(),
                    StringUtils.join(messages, "&&&"));
        }
    }

    static class Message {

        public final String userName;
        public final String content;

        public Message(String name, String content) {
            this.userName = name;
            this.content = content;
        }

        @Override
        public String toString() {
            return userName + " " + content;
        }
    }

    public static void main(String[] args)
            throws XMLStreamException, IOException {
        File folder = new File("/xml/");
        List<ConversationInfo> m = new ArrayList<>();
        File[] listOfFiles = folder.listFiles();
        for (int i = 0; i < listOfFiles.length; i++) {
            File file = listOfFiles[i];
            String fileName = file.getAbsolutePath();
            System.out.println("File" + file);
            if (file.isFile() && file.getName().endsWith(".xml")) {
                XMLInputFactory xf = XMLInputFactory.newFactory();
                try (FileInputStream fin = new FileInputStream(file)) {
                    XMLStreamReader xr = xf.createXMLStreamReader(fin);
                    LOOP:
                    while (xr.hasNext()) {
                        int event = xr.next();
                        switch (event) {
                            case XMLStreamConstants.START_ELEMENT: {
                                String elName = xr.getLocalName();
                                if (CONVERSATION.equals(elName)) {
                                    ConversationInfo convInfo = parseConversation(xr, file.getName());
                                    if (convInfo != null) {
                                        m.add(convInfo);
                                    }
                                }
                                break;
                            }
                            case XMLStreamConstants.END_ELEMENT: {
                                String elName = xr.getLocalName();
                                if (FILE_DUMP.equals(elName)) {
                                    break LOOP;
                                }
                                break;
                            }
                            case XMLStreamConstants.END_DOCUMENT:
                                throw new IllegalStateException("xml not well-formed: <"
                                        + FILE_DUMP + "> tag not closed");
                        }
                    }
                }
            }
        }
        //  ConversationInfo c = new ConversationInfo();

        try (FileWriter w = new FileWriter("output.txt")) {
            int i = 1;
            for (ConversationInfo convInfo : m) {
                convInfo.orderInFile = i;
                w.write(String.format("%d %s\n", i++, convInfo));
            }
        }

    }

    private static ConversationInfo parseConversation(XMLStreamReader xr, String fileName)
            throws XMLStreamException {
        ConversationInfo convInfo = new ConversationInfo();
        convInfo.fileName = fileName;
        while (xr.hasNext()) {
            int event = xr.next();
            switch (event) {
                case XMLStreamConstants.START_ELEMENT: {
                    String elName = xr.getLocalName();
                    if (MESSAGE.equals(elName)) {
                        Message message = parseMessage(xr);
                        if (message != null) {
                            convInfo.messages.add(message);
                            convInfo.users.add(message.userName);
                            convInfo.map.put(message.userName, message.content);
                        }
                    } else if (START_TIME.equals(elName)) {
                        convInfo.startTimeStr = xr.getElementText();
                    } else if (ROOM_ID.equals(elName)) {
                        convInfo.conversationId = xr.getElementText();
                    }
                    break;
                }
                case XMLStreamConstants.END_ELEMENT: {
                    String elName = xr.getLocalName();
                    if (CONVERSATION.equals(elName)) {
                        return convInfo;
                    }
                    break;
                }
                case XMLStreamConstants.END_DOCUMENT:
                    throw new XMLStreamException("xml not well-formed: <"
                            + CONVERSATION + "> tag not closed");
            }
        }

        throw new XMLStreamException(
                "unexpected end of xml file while parsing a conversation");
    }

    private static Message parseMessage(XMLStreamReader xr)
            throws XMLStreamException {
        String userName = null;
        String content = null;
        while (xr.hasNext()) {
            int event = xr.next();
            switch (event) {
                case XMLStreamConstants.START_ELEMENT: {
                    String elName = xr.getLocalName();
                    if (LOGIN_NAME.equals(elName)) {
                        userName = xr.getElementText();
                    } else if (CONTENT.equals(elName)) {
                        content = StringUtils.trimToEmpty(xr.getElementText());
                    }
                    break;
                }
                case XMLStreamConstants.END_ELEMENT: {
                    String elName = xr.getLocalName();
                    if (MESSAGE.equals(elName)) {
                        return new Message(userName, content);
                    }
                    break;
                }
                case XMLStreamConstants.END_DOCUMENT:
                    throw new XMLStreamException("xml not well-formed: <"
                            + MESSAGE + "> tag not closed");
            }
        }
        throw new XMLStreamException(
                "unexpected end of xml file while parsing a message");
    }
}

我的 input.xml 是：

<?xml version="1.0" encoding="UTF-8"?>
<!-- Data provided by Bloomberg LP. -->
<FileDump>
    <Version>IBXML 1.3</Version>
    <Conversation Perspective=" " RoomType="P">
        <RoomID>PCHAT-0x3000001CA8361</RoomID>
        <StartTime>03/31/2016 13:39:01</StartTime>
        <StartTimeUTC>1459431541</StartTimeUTC>
        <ParticipantEntered InteractionType="N" DeviceType="M">
            <User>
                <LoginName>SWONG00</LoginName>
                <FirstName>STEPHEN</FirstName>
                <LastName>WONG</LastName>
                <UUID>4397109</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>231115</AccountNumber>
                <CompanyName>DBS BANK LIMITED HON</CompanyName>
                <EmailAddress>SWONG00@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>03/31/2016 13:39:01</DateTime>
            <DateTimeUTC>1459431541</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantEntered>
        <ParticipantEntered InteractionType="N" DeviceType="M">
            <User>
                <LoginName>G_LO</LoginName>
                <FirstName>GARY</FirstName>
                <LastName>LO</LastName>
                <UUID>7054548</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>91189</AccountNumber>
                <CompanyName>DBS BANK (HONG KONG)</CompanyName>
                <EmailAddress>G_LO@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>
            </User>
            <DateTime>03/31/2016 14:56:22</DateTime>
            <DateTimeUTC>1459436182</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantEntered>
        <ParticipantLeft InteractionType="N" DeviceType="M">
            <User>
                <LoginName>G_LO</LoginName>
                <FirstName>GARY</FirstName>
                <LastName>LO</LastName>
                <UUID>7054548</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>91189</AccountNumber>
                <CompanyName>DBS BANK (HONG KONG)</CompanyName>
                <EmailAddress>G_LO@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>
            </User>
            <DateTime>03/31/2016 19:30:01</DateTime>
            <DateTimeUTC>1459452601</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantLeft>
        <ParticipantLeft InteractionType="N" DeviceType="M">
            <User>
                <LoginName>SWONG00</LoginName>
                <FirstName>STEPHEN</FirstName>
                <LastName>WONG</LastName>
                <UUID>4397109</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>231115</AccountNumber>
                <CompanyName>DBS BANK LIMITED HON</CompanyName>
                <EmailAddress>SWONG00@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>03/31/2016 19:33:56</DateTime>
            <DateTimeUTC>1459452836</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantLeft>
        <ParticipantEntered InteractionType="N" DeviceType="M">
            <User>
                <LoginName>SWONG00</LoginName>
                <FirstName>STEPHEN</FirstName>
                <LastName>WONG</LastName>
                <UUID>4397109</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>231115</AccountNumber>
                <CompanyName>DBS BANK LIMITED HON</CompanyName>
                <EmailAddress>SWONG00@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>03/31/2016 19:45:16</DateTime>
            <DateTimeUTC>1459453516</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantEntered>
        <ParticipantLeft InteractionType="N" DeviceType="M">
            <User>
                <LoginName>SWONG00</LoginName>
                <FirstName>STEPHEN</FirstName>
                <LastName>WONG</LastName>
                <UUID>4397109</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>231115</AccountNumber>
                <CompanyName>DBS BANK LIMITED HON</CompanyName>
                <EmailAddress>SWONG00@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>03/31/2016 23:08:09</DateTime>
            <DateTimeUTC>1459465689</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantLeft>
        <ParticipantEntered InteractionType="N" DeviceType="M">
            <User>
                <LoginName>G_LO</LoginName>
                <FirstName>GARY</FirstName>
                <LastName>LO</LastName>
                <UUID>7054548</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>91189</AccountNumber>
                <CompanyName>DBS BANK (HONG KONG)</CompanyName>
                <EmailAddress>G_LO@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>
            </User>
            <DateTime>03/31/2016 23:14:23</DateTime>
            <DateTimeUTC>1459466063</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantEntered>
        <Message InteractionType="N">
            <User>
                <LoginName>G_LO</LoginName>
                <FirstName>GARY</FirstName>
                <LastName>LO</LastName>
                <UUID>7054548</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>91189</AccountNumber>
                <CompanyName>DBS BANK (HONG KONG)</CompanyName>
                <EmailAddress>G_LO@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>
            </User>
            <DateTime>04/01/2016 00:10:57</DateTime>
            <DateTimeUTC>1459469457</DateTimeUTC>
            <Content>abcdefgghhhhhh</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <ParticipantEntered InteractionType="N" DeviceType="M">
            <User>
                <LoginName>WVU</LoginName>
                <FirstName>WHEELOCK</FirstName>
                <LastName>VU</LastName>
                <UUID>8266852</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>91189</AccountNumber>
                <CompanyName>DBS BANK (HONG KONG)</CompanyName>
                <EmailAddress>WVU@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>WHEELOCKVU@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>04/01/2016 00:14:05</DateTime>
            <DateTimeUTC>1459469645</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantEntered>
        <ParticipantEntered InteractionType="N">
            <User>
                <LoginName>FCHAN95</LoginName>
                <FirstName>FLORENCE</FirstName>
                <LastName>CHAN</LastName>
                <CompanyName>GOLDMAN SACHS (ASIA)</CompanyName>
                <EmailAddress>FCHAN95@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress />
            </User>
            <DateTime>04/01/2016 00:29:19</DateTime>
            <DateTimeUTC>1459470559</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantEntered>
        <Message InteractionType="N">
            <User>
                <LoginName>FCHAN95</LoginName>
                <FirstName>FLORENCE</FirstName>
                <LastName>CHAN</LastName>
                <CompanyName>GOLDMAN SACHS (ASIA)</CompanyName>
                <EmailAddress>FCHAN95@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress />
            </User>
            <DateTime>04/01/2016 00:29:19</DateTime>
            <DateTimeUTC>1459470559</DateTimeUTC>
            <Content>ajdakjgdljsgdsafhkafa</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <Message InteractionType="N">
            <User>
                <LoginName>FCHAN95</LoginName>
                <FirstName>FLORENCE</FirstName>
                <LastName>CHAN</LastName>
                <CompanyName>GOLDMAN SACHS (ASIA)</CompanyName>
                <EmailAddress>FCHAN95@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress />
            </User>
            <DateTime>04/01/2016 00:29:19</DateTime>
            <DateTimeUTC>1459470559</DateTimeUTC>
            <Content>akjdgljsafdlshf;kdsjf</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <Message InteractionType="N">
            <User>
                <LoginName>WVU</LoginName>
                <FirstName>WHEELOCK</FirstName>
                <LastName>VU</LastName>
                <UUID>8266852</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>91189</AccountNumber>
                <CompanyName>DBS BANK (HONG KONG)</CompanyName>
                <EmailAddress>WVU@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>WHEELOCKVU@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>04/01/2016 00:39:32</DateTime>
            <DateTimeUTC>1459471172</DateTimeUTC>
            <Content>sagdksajdlsahd</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <ParticipantEntered InteractionType="N" DeviceType="M">
            <User>
                <LoginName>SWONG00</LoginName>
                <FirstName>STEPHEN</FirstName>
                <LastName>WONG</LastName>
                <UUID>4397109</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>231115</AccountNumber>
                <CompanyName>DBS BANK LIMITED HON</CompanyName>
                <EmailAddress>SWONG00@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>04/01/2016 01:01:27</DateTime>
            <DateTimeUTC>1459472487</DateTimeUTC>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </ParticipantEntered>
        <Message InteractionType="N">
            <User>
                <LoginName>SWONG00</LoginName>
                <FirstName>STEPHEN</FirstName>
                <LastName>WONG</LastName>
                <UUID>4397109</UUID>
                <FirmNumber>13133</FirmNumber>
                <AccountNumber>231115</AccountNumber>
                <CompanyName>DBS BANK LIMITED HON</CompanyName>
                <EmailAddress>SWONG00@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>
            </User>
            <DateTime>04/01/2016 01:31:29</DateTime>
            <DateTimeUTC>1459474289</DateTimeUTC>
            <Content>ajdslsahdsj;a</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <Message InteractionType="N" DeviceType="M">
            <User>
                <LoginName>FCHAN95</LoginName>
                <FirstName>FLORENCE</FirstName>
                <LastName>CHAN</LastName>
                <CompanyName>GOLDMAN SACHS (ASIA)</CompanyName>
                <EmailAddress>FCHAN95@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress />
            </User>
            <DateTime>04/01/2016 02:49:46</DateTime>
            <DateTimeUTC>1459478986</DateTimeUTC>
            <Content>sagdkjsagdkjashdlasjd</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <Message InteractionType="N" DeviceType="M">
            <User>
                <LoginName>FCHAN95</LoginName>
                <FirstName>FLORENCE</FirstName>
                <LastName>CHAN</LastName>
                <CompanyName>GOLDMAN SACHS (ASIA)</CompanyName>
                <EmailAddress>FCHAN95@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress />
            </User>
            <DateTime>04/01/2016 02:49:46</DateTime>
            <DateTimeUTC>1459478986</DateTimeUTC>
            <Content>jsdhkshdksjdlsjdlks</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <Message InteractionType="N" DeviceType="M">
            <User>
                <LoginName>FCHAN95</LoginName>
                <FirstName>FLORENCE</FirstName>
                <LastName>CHAN</LastName>
                <CompanyName>GOLDMAN SACHS (ASIA)</CompanyName>
                <EmailAddress>FCHAN95@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress />
            </User>
            <DateTime>04/01/2016 03:47:37</DateTime>
            <DateTimeUTC>1459482457</DateTimeUTC>
            <Content>jshdkshdksjdlskld</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <Message InteractionType="N" DeviceType="M">
            <User>
                <LoginName>FCHAN95</LoginName>
                <FirstName>FLORENCE</FirstName>
                <LastName>CHAN</LastName>
                <CompanyName>GOLDMAN SACHS (ASIA)</CompanyName>
                <EmailAddress>FCHAN95@Bloomberg.net</EmailAddress>
                <CorporateEmailAddress />
            </User>
            <DateTime>04/01/2016 03:47:37</DateTime>
            <DateTimeUTC>1459482457</DateTimeUTC>
            <Content>aasasasasas</Content>
            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>
        </Message>
        <EndTime>04/01/2016 03:47:37</EndTime>
        <EndTimeUTC>1459482457</EndTimeUTC>
    </Conversation>
</FileDump>

目前我正在显示用户和内容，但我想打印

userName(CountOfMessages UserSent)+userName(CountOfMessages UserSent)

例如：G_LO(1)+FCHAN95(6)+WVU(1)+SWONG00(1)

我试过 HashMap<String, Integer> 但它没有按预期工作。 Java 8 个功能也无法正常工作。也试过 Multiset Guava 但无济于事。

Answer 1

使用像 Saxon 9.7 EE 这样的 XSLT 3.0 处理器，您可以通过使用累加器的样式表以声明方式完成此操作：

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:xs="http://www.w3.org/2001/XMLSchema"
    xmlns:math="http://www.w3.org/2005/xpath-functions/math"
    xmlns:map="http://www.w3.org/2005/xpath-functions/map"
    exclude-result-prefixes="xs math map"
    version="3.0">

    <xsl:accumulator name="message-count" as="map(xs:string, xs:integer)" initial-value="map{}" streamable="yes">
        <xsl:accumulator-rule
            match="Message/User/LoginName/text()"
            select="if (map:contains($value, .))
                    then map:put($value, string(), map:get($value, .) + 1)
                    else map:put($value, string(), 1)"/>
    </xsl:accumulator>

    <xsl:mode streamable="yes" on-no-match="shallow-skip"/>
    <xsl:global-context-item streamable="yes" use-accumulators="message-count"/>

    <xsl:output method="text"/>

    <xsl:template match="/*">
        <xsl:apply-templates/>
        <xsl:value-of select="serialize(accumulator-after('message-count'), map { 'method' : 'adaptive' })"/>
    </xsl:template>

</xsl:stylesheet>

您发布的示例的输出是 map{"SWONG00":1,"FCHAN95":6,"WVU":1,"G_LO":1}。

Answer 2

您可以使用 SAX（注意，不是 StAX）轻松实现它。您也应该能够使用 StAX 执行此操作。当我这样做时，我会 post 更新。 SAX上的一个参考实现如下

import java.io.StringReader;
import java.util.HashMap;

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

public class NumCountHandler extends DefaultHandler {

    private HashMap<String, Integer> countOfNum = new HashMap<String, Integer>();
    boolean isStartTagPass = false;

    @Override
    public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
        if (qName.equalsIgnoreCase("LoginName")) {
            isStartTagPass = true;
        }
    }

    @Override
    public void characters(char[] ch, int start, int length) throws SAXException {
        String attributeNum = new String(ch, start, length);
        if (isStartTagPass) {
            if (countOfNum.containsKey(attributeNum)) {
                Integer count = countOfNum.get(attributeNum);
                countOfNum.put(attributeNum, new Integer(count.intValue() + 1));
            } else {
                countOfNum.put(attributeNum, new Integer(1));
            }
        }
    }

    @Override
    public void endElement(String uri, String localName, String qName) throws SAXException {
        if (qName.equalsIgnoreCase("LoginName")) {
            isStartTagPass = false;
        }
    }

    public static void main(String[] args) {

        try {
            String xml = "<FileDump>    <Version>IBXML 1.3</Version>    <Conversation Perspective=\" \" RoomType=\"P\">        <RoomID>PCHAT-0x3000001CA8361</RoomID>        <StartTime>03/31/2016 13:39:01</StartTime>        <StartTimeUTC>1459431541</StartTimeUTC>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 13:39:01</DateTime>            <DateTimeUTC>1459431541</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 14:56:22</DateTime>            <DateTimeUTC>1459436182</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantLeft InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 19:30:01</DateTime>            <DateTimeUTC>1459452601</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantLeft>        <ParticipantLeft InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 19:33:56</DateTime>            <DateTimeUTC>1459452836</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantLeft>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 19:45:16</DateTime>            <DateTimeUTC>1459453516</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantLeft InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 23:08:09</DateTime>            <DateTimeUTC>1459465689</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantLeft>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 23:14:23</DateTime>            <DateTimeUTC>1459466063</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <Message InteractionType=\"N\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 00:10:57</DateTime>            <DateTimeUTC>1459469457</DateTimeUTC>            <Content>abcdefgghhhhhh</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>WVU</LoginName><FirstName>WHEELOCK</FirstName><LastName>VU</LastName><UUID>8266852</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>WVU@Bloomberg.net</EmailAddress><CorporateEmailAddress>WHEELOCKVU@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 00:14:05</DateTime>            <DateTimeUTC>1459469645</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantEntered InteractionType=\"N\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 00:29:19</DateTime>            <DateTimeUTC>1459470559</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <Message InteractionType=\"N\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 00:29:19</DateTime>            <DateTimeUTC>1459470559</DateTimeUTC>            <Content>ajdakjgdljsgdsafhkafa</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 00:29:19</DateTime>            <DateTimeUTC>1459470559</DateTimeUTC>            <Content>akjdgljsafdlshf;kdsjf</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\">            <User><LoginName>WVU</LoginName><FirstName>WHEELOCK</FirstName><LastName>VU</LastName><UUID>8266852</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>WVU@Bloomberg.net</EmailAddress><CorporateEmailAddress>WHEELOCKVU@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 00:39:32</DateTime>            <DateTimeUTC>1459471172</DateTimeUTC>            <Content>sagdksajdlsahd</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 01:01:27</DateTime>            <DateTimeUTC>1459472487</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <Message InteractionType=\"N\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 01:31:29</DateTime>            <DateTimeUTC>1459474289</DateTimeUTC>            <Content>ajdslsahdsj;a</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 02:49:46</DateTime>            <DateTimeUTC>1459478986</DateTimeUTC>            <Content>sagdkjsagdkjashdlasjd</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 02:49:46</DateTime>            <DateTimeUTC>1459478986</DateTimeUTC>            <Content>jsdhkshdksjdlsjdlks</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 03:47:37</DateTime>            <DateTimeUTC>1459482457</DateTimeUTC>            <Content>jshdkshdksjdlskld</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 03:47:37</DateTime>            <DateTimeUTC>1459482457</DateTimeUTC>            <Content>aasasasasas</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <EndTime>04/01/2016 03:47:37</EndTime>        <EndTimeUTC>1459482457</EndTimeUTC>    </Conversation></FileDump>";
            ;
            InputSource is = new InputSource(new StringReader(xml));

            SAXParserFactory factory = SAXParserFactory.newInstance();
            SAXParser saxParser = factory.newSAXParser();
            NumCountHandler userhandler = new NumCountHandler();
            saxParser.parse(is, userhandler);

            userhandler.countOfNum
                    .forEach((k, v) -> System.out.print(k +"("+v+") "));

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

这会打印：WVU(2)+G_LO(4)+FCHAN95(7)+SWONG00(6)+

=====添加了基于 StaX 的实现==========

Java8 项功能绝对可以改进。另外，我只为一个小飞行员使用了静态变量，应该能够使用 class 变量以及一些折射

import java.io.StringReader;
import java.util.HashMap;

import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.events.Characters;
import javax.xml.stream.events.XMLEvent;

public class NumCountHandlerStax {

    private boolean isStartTagPass = false;

    static private void groupAndProcess(Object object, HashMap<String, Integer> countOfNum,
            NumCountHandlerStax staxBasedCounter) {
        XMLEvent event = (XMLEvent) object;
        if (event.isStartElement() && event.asStartElement().getName().getLocalPart().equals("LoginName")) {
            staxBasedCounter.isStartTagPass = true;
        } else if (event.isEndElement() && event.asEndElement().getName().getLocalPart().equals("LoginName")) {
            staxBasedCounter.isStartTagPass = false;
        } else if (staxBasedCounter.isStartTagPass && event.isCharacters()) {
            Characters characters = event.asCharacters();
            String attributeNum = characters.getData();
            if (countOfNum.containsKey(attributeNum)) {
                Integer count = countOfNum.get(attributeNum);
                countOfNum.put(attributeNum, new Integer(count.intValue() + 1));
            } else {
                countOfNum.put(attributeNum, new Integer(1));
            }

        }

    }

    public static void main(String[] args) {

        try {
            NumCountHandlerStax staxBasedCounter = new NumCountHandlerStax();
            HashMap<String, Integer> countOfNum = new HashMap<String, Integer>();
            String xml = "<FileDump>    <Version>IBXML 1.3</Version>    <Conversation Perspective=\" \" RoomType=\"P\">        <RoomID>PCHAT-0x3000001CA8361</RoomID>        <StartTime>03/31/2016 13:39:01</StartTime>        <StartTimeUTC>1459431541</StartTimeUTC>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 13:39:01</DateTime>            <DateTimeUTC>1459431541</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 14:56:22</DateTime>            <DateTimeUTC>1459436182</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantLeft InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 19:30:01</DateTime>            <DateTimeUTC>1459452601</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantLeft>        <ParticipantLeft InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 19:33:56</DateTime>            <DateTimeUTC>1459452836</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantLeft>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 19:45:16</DateTime>            <DateTimeUTC>1459453516</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantLeft InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 23:08:09</DateTime>            <DateTimeUTC>1459465689</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantLeft>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>03/31/2016 23:14:23</DateTime>            <DateTimeUTC>1459466063</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <Message InteractionType=\"N\">            <User><LoginName>G_LO</LoginName><FirstName>GARY</FirstName><LastName>LO</LastName><UUID>7054548</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>G_LO@Bloomberg.net</EmailAddress><CorporateEmailAddress>garyloyc@dbs.com</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 00:10:57</DateTime>            <DateTimeUTC>1459469457</DateTimeUTC>            <Content>abcdefgghhhhhh</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>WVU</LoginName><FirstName>WHEELOCK</FirstName><LastName>VU</LastName><UUID>8266852</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>WVU@Bloomberg.net</EmailAddress><CorporateEmailAddress>WHEELOCKVU@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 00:14:05</DateTime>            <DateTimeUTC>1459469645</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <ParticipantEntered InteractionType=\"N\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 00:29:19</DateTime>            <DateTimeUTC>1459470559</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <Message InteractionType=\"N\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 00:29:19</DateTime>            <DateTimeUTC>1459470559</DateTimeUTC>            <Content>ajdakjgdljsgdsafhkafa</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 00:29:19</DateTime>            <DateTimeUTC>1459470559</DateTimeUTC>            <Content>akjdgljsafdlshf;kdsjf</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\">            <User><LoginName>WVU</LoginName><FirstName>WHEELOCK</FirstName><LastName>VU</LastName><UUID>8266852</UUID><FirmNumber>13133</FirmNumber><AccountNumber>91189</AccountNumber><CompanyName>DBS BANK (HONG KONG)</CompanyName><EmailAddress>WVU@Bloomberg.net</EmailAddress><CorporateEmailAddress>WHEELOCKVU@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 00:39:32</DateTime>            <DateTimeUTC>1459471172</DateTimeUTC>            <Content>sagdksajdlsahd</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <ParticipantEntered InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 01:01:27</DateTime>            <DateTimeUTC>1459472487</DateTimeUTC>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </ParticipantEntered>        <Message InteractionType=\"N\">            <User><LoginName>SWONG00</LoginName><FirstName>STEPHEN</FirstName><LastName>WONG</LastName><UUID>4397109</UUID><FirmNumber>13133</FirmNumber><AccountNumber>231115</AccountNumber><CompanyName>DBS BANK LIMITED HON</CompanyName><EmailAddress>SWONG00@Bloomberg.net</EmailAddress><CorporateEmailAddress>STEPHENWONGWE@DBS.COM</CorporateEmailAddress>            </User>            <DateTime>04/01/2016 01:31:29</DateTime>            <DateTimeUTC>1459474289</DateTimeUTC>            <Content>ajdslsahdsj;a</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 02:49:46</DateTime>            <DateTimeUTC>1459478986</DateTimeUTC>            <Content>sagdkjsagdkjashdlasjd</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 02:49:46</DateTime>            <DateTimeUTC>1459478986</DateTimeUTC>            <Content>jsdhkshdksjdlsjdlks</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 03:47:37</DateTime>            <DateTimeUTC>1459482457</DateTimeUTC>            <Content>jshdkshdksjdlskld</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <Message InteractionType=\"N\" DeviceType=\"M\">            <User><LoginName>FCHAN95</LoginName><FirstName>FLORENCE</FirstName><LastName>CHAN</LastName><CompanyName>GOLDMAN SACHS (ASIA)</CompanyName><EmailAddress>FCHAN95@Bloomberg.net</EmailAddress><CorporateEmailAddress />            </User>            <DateTime>04/01/2016 03:47:37</DateTime>            <DateTimeUTC>1459482457</DateTimeUTC>            <Content>aasasasasas</Content>            <ConversationID>PCHAT-0x3000001CA8361</ConversationID>        </Message>        <EndTime>04/01/2016 03:47:37</EndTime>        <EndTimeUTC>1459482457</EndTimeUTC>    </Conversation></FileDump>";
            ;
            XMLInputFactory xmlInputFactory = XMLInputFactory.newInstance();
            XMLEventReader xmlEventReader = xmlInputFactory.createXMLEventReader(new StringReader(xml));
            xmlEventReader.forEachRemaining(event -> groupAndProcess(event, countOfNum, staxBasedCounter));
            countOfNum.forEach((k, v) -> System.out.print(k + "(" + v + ") "));

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}
Prints `WVU(2) G_LO(4) FCHAN95(7) SWONG00(6)`

Answer 3

这是基于XPath和VTD的例子-XML。 VTD-XML 不会像 DOM 这样的大 XML 爆炸。 XPath 使代码逻辑易于理解，易于维护。如果您想计算不同的东西，只需输入不同的 xpath 查询即可。

import java.util.HashMap;
import com.ximpleware.*;. 
public class stats {
    public static void main(String[] s)throws VTDException{
        VTDGen vg = new VTDGen();
        if (!vg.parseFile("d:\xml\dump.xml", false)){
            System.out.println("parsing error");
            return;
        }
        VTDNav vn = vg.getNav();
        AutoPilot ap = new AutoPilot(vn);
        HashMap <String,Integer> hit = new HashMap<String, Integer>();
        ap.selectXPath("/FileDump/Conversation/Message/User/LoginName/text()");
        int i=0;
        while((i=ap.evalXPath())!=-1){
            String s1 = vn.toNormalizedString(i);
            if (hit.containsKey(s1)){
                Integer it = hit.get(s1);
                hit.put(s1, new Integer(it.intValue()+1));
            }else{
                hit.put(s1, new Integer(1));
            }
        }

        System.out.println(hit.toString());
    }
}

使用 Java StAX 解析 XML - 计算内容标签的数量

Parse XML using Java StAX - Count number of content tags

java

xml

stax

guava