Java 操作 XML(12)--XPP3 使用

XPP3(XML Pull Parser)是一个非常快的XML解析器，它可以很方便地解析 XML 文档。本文主要介绍 XPP3 的基本使用，文中所使用到的软件版本：Java 1.8.0_181、xpp3 1.4.1c。

1、引入依赖

<dependency>
    <groupId>xpp3</groupId>
    <artifactId>xpp3</artifactId>
    <version>1.1.4c</version>
</dependency>

2、XML样例文件

<?xml version="1.0" encoding="utf-8" ?>
<school:grade xmlns:school="http://www.w3.org/TR/html4/school/">
    <school:student rollno="1" school:age="10">
        <school:firstname>cxx1</school:firstname>
        <lastname>Bob1</lastname>
        <nickname>stars1</nickname>
        <marks>85</marks>
    </school:student>
    <student rollno="2">
        <firstname>cxx2</firstname>
        <lastname>Bob2</lastname>
        <nickname>stars2</nickname>
        <marks>85</marks>
    </student>
    <student rollno="3">
        <firstname>cxx3</firstname>
        <lastname>Bob3</lastname>
        <nickname>stars3</nickname>
        <marks>85</marks>
    </student>
</school:grade>

3、XPP3使用例子

package com.abc.demo.general.xml;

import org.apache.commons.lang.StringUtils;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;

import java.util.ArrayList;
import java.util.List;

/**
 * Xpp3使用
 */
public class Xpp3Case {
    private static Logger logger = LoggerFactory.getLogger(Xpp3Case.class);

    /**
     * 解析xml
     * @throws Exception
     */
    @Test
    public void parse() throws Exception {
        XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
        factory.setNamespaceAware(true);
        XmlPullParser xpp = factory.newPullParser();
        xpp.setInput(Xpp3Case.class.getResourceAsStream("student.xml"), "utf-8");

        List<Student> students = new ArrayList<>();
        Student student = null;
        String text = "";
        int eventType = xpp.getEventType();
        while (true) {
            if (eventType == XmlPullParser.START_DOCUMENT) {
                logger.info("Start of Document");
            } else if (eventType == XmlPullParser.START_TAG) {
                if ("student".equals(xpp.getName())) {
                    student = new Student();
                    students.add(student);
                    student.setRollno(Integer.parseInt(xpp.getAttributeValue("", "rollno")));
                    String age = xpp.getAttributeValue("http://www.w3.org/TR/html4/school/", "age");
                    if (StringUtils.isNotBlank(age)) {
                        student.setAge(Integer.parseInt(age));
                    }
                }
            } else if (eventType == XmlPullParser.END_TAG) {
                if ("firstname".equals(xpp.getName())) {
                    student.setFirstname(text);
                } else if ("lastname".equals(xpp.getName())) {
                    student.setLastname(text);
                } else if ("nickname".equals(xpp.getName())) {
                    student.setNickname(text);
                } else if ("marks".equals(xpp.getName())) {
                    student.setMarks(text);
                }
            } else if (eventType == XmlPullParser.TEXT) {
                text = xpp.getText();
            } else if (eventType == XmlPullParser.END_DOCUMENT) {
                logger.info("End of Document");
                break;
            }
            eventType = xpp.next();
        }

        logger.info(students.toString());
    }
}

Student实体类：

package com.abc.demo.general.xml;

/**
 * 学生
 */
public class Student {
    private int rollno;
    private int age;
    private String firstname;
    private String lastname;
    private String nickname;
    private String marks;

    public Student() {}

    public Student(int rollno, int age, String firstname, String lastname, String nickname, String marks) {
        this.rollno = rollno;
        this.age = age;
        this.firstname = firstname;
        this.lastname = lastname;
        this.nickname = nickname;
        this.marks = marks;
    }

    public int getRollno() {
        return rollno;
    }

    public void setRollno(int rollno) {
        this.rollno = rollno;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getFirstname() {
        return firstname;
    }

    public void setFirstname(String firstname) {
        this.firstname = firstname;
    }

    public String getLastname() {
        return lastname;
    }

    public void setLastname(String lastname) {
        this.lastname = lastname;
    }

    public String getNickname() {
        return nickname;
    }

    public void setNickname(String nickname) {
        this.nickname = nickname;
    }

    public String getMarks() {
        return marks;
    }

    public void setMarks(String marks) {
        this.marks = marks;
    }

    @Override
    public String toString() {
        return "Student{" +
                "rollno=" + rollno +
                ", age=" + age +
                ", firstname='" + firstname + '\'' +
                ", lastname='" + lastname + '\'' +
                ", nickname='" + nickname + '\'' +
                ", marks='" + marks + '\'' +
                '}';
    }
}