JAVA日常开发中读写XML的方法详解

<?xml version="1.0" encoding="UTF-8"?>
<bookstore>
    <book category="cooking">
        <title lang="en">Everyday Italian</title>
        <author>Giada De Laurentiis</author>
        <year>2005</year>
        <price>30.00</price>
    </book>
</bookstore>

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import java.io.File;

public class ReadXMLWithDOM {
    public static void main(String[] args) {
        try {
            File xmlFile = new File("books.xml");
            DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
            Document doc = dBuilder.parse(xmlFile);
            doc.getDocumentElement().normalize();

            NodeList nList = doc.getElementsByTagName("book");
            for (int i = 0; i < nList.getLength(); i++) {
                Node nNode = nList.item(i);
                if (nNode.getNodeType() == Node.ELEMENT_NODE) {
                    Element eElement = (Element) nNode;
                    System.out.println("Book title: " + eElement.getElementsByTagName("title").item(0).getTextContent());
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import java.io.File;

public class ReadXMLWithSAX {
    public static void main(String[] args) {
        try {
            File xmlFile = new File("books.xml");
            SAXParserFactory factory = SAXParserFactory.newInstance();
            SAXParser saxParser = factory.newSAXParser();
            MyHandler handler = new MyHandler();
            saxParser.parse(xmlFile, handler);
            System.out.println("Number of books: " + handler.getBookCount());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

class MyHandler extends DefaultHandler {
    private int bookCount = 0;

    @Override
    public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
        if (qName.equalsIgnoreCase("book")) {
            bookCount++;
        }
    }

    public int getBookCount() {
        return bookCount;
    }
}

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class WriteXMLWithDOM {
    public static void main(String[] args) {
        try {
            DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
            Document doc = dBuilder.newDocument();

            Element bookstore = doc.createElement("bookstore");
            doc.appendChild(bookstore);

            Element book = doc.createElement("book");
            bookstore.appendChild(book);

            Element title = doc.createElement("title");
            title.setTextContent("New Book");
            book.appendChild(title);

            TransformerFactory transformerFactory = TransformerFactory.newInstance();
            Transformer transformer = transformerFactory.newTransformer();
            DOMSource source = new DOMSource(doc);
            StreamResult result = new StreamResult(new File("new_books.xml"));
            transformer.transform(source, result);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import java.util.ArrayList;
import java.util.List;

class Book {
    private String title;
    private String author;
    private int year;
    private double price;

    // 构造函数、getter和setter方法省略
}

class Bookstore {
    private List<Book> books = new ArrayList<>();

    public void addBook(Book book) {
        books.add(book);
    }

    // 其他方法省略
}

public class WriteXMLWithJAXB {
    public static void main(String[] args) {
        try {
            Bookstore bookstore = new Bookstore();
            Book book = new Book();
            book.setTitle("Another New Book");
            book.setAuthor("New Author");
            book.setYear(2024);
            book.setPrice(35.0);
            bookstore.addBook(book);

            JAXBContext jaxbContext = JAXBContext.newInstance(Bookstore.class);
            Marshaller jaxbMarshaller = jaxbContext.createMarshaller();
            jaxbMarshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
            jaxbMarshaller.marshal(bookstore, new File("jaxb_books.xml"));
        } catch (JAXBException e) {
            e.printStackTrace();
        }
    }
}