Heim  >  Artikel  >  Backend-Entwicklung  >  Wie Android DOM und SAXParserFactory zum Parsen von XML-Dateien verwendet

Wie Android DOM und SAXParserFactory zum Parsen von XML-Dateien verwendet

黄舟
黄舟Original
2017-02-20 15:00:211692Durchsuche

Für die folgende XML-Datei:


<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<books>  
    <book email="zhoujunhui">  
        <name>rjzjh</name>  
        <price>jjjjjj</price>  
    </book>  
     <book email="aaaaaaaaa">  
        <name>bbbb</name>  
        <price>ccc</price>  
    </book>  
</books>


So analysiert:



import java.util.ArrayList;

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 android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.res.AssetManager;
import android.os.Bundle;
import android.util.Log;

public class TestActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		XmlReader();
		for(int i=0;i<list.size();i++) {
			Book book = list.get(i);
			Log.d("TAG", "name="+book.name+"email="+book.email);
		}
	}


	public void XmlReader() {
		Document doc = null;
		AssetManager assetManager = this.getAssets();
		DocumentBuilder docBuilder = null;
		DocumentBuilderFactory docBuilderFactory = null;
		try {
			docBuilderFactory = DocumentBuilderFactory.newInstance();
			docBuilder = docBuilderFactory.newDocumentBuilder();
			doc = docBuilder.parse(assetManager.open("test1.xml"));
			Element root = doc.getDocumentElement();
			NodeList books = root.getChildNodes();
			if (books != null) {
				for (int i = 0; i < books.getLength(); i++) {
					Node book = books.item(i);
					Book mybook = null;
					if (book.getNodeType() == Node.ELEMENT_NODE) {
						//这里才表示这个是<book>节点
						mybook = new Book();
						String email = book.getAttributes()
								.getNamedItem("email").getNodeValue();
						mybook.email = email;
						
						for (Node node = book.getFirstChild(); node != null; node = node
								.getNextSibling()) {
							
							if (node.getNodeType() == Node.ELEMENT_NODE) {
								if (node.getNodeName().equals("name")) {
									String name1 = node.getFirstChild()
											.getNodeValue();
									mybook.name = name1;
								}
								if (node.getNodeName().equals("price")) {
									String price = node.getFirstChild()
											.getNodeValue();
									mybook.price = price;
								}
							}
							
						}
						
						list.add(mybook);
					}
					
				}
			}
		} catch (Exception e) {
			e.printStackTrace();
		}

	}
	
	private ArrayList<Book> list = new ArrayList<Book>();
	
	private class Book{
		String email;
		String name;
		String price;
	}


Verwendung von SAXParserFactory:


@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		SAXParserFactory factory = SAXParserFactory.newInstance();

		try {
			SAXParser saxParser = factory.newSAXParser();
			InputStream is = this.getAssets().open("test1.xml", Context.MODE_PRIVATE);
			saxParser.parse(is, new MyDefaultHandler());
		} catch (Exception ex) {

		}
		System.out.println("===size=" + list.size());
		for (int i = 0; i < list.size(); i++) {
			Book book = list.get(i);
			Log.d("TAG", "name=" + book.name + "email=" + book.email);
		}
	}

	protected String getElementName(String name, String qName) {
		if ("".equals(name)) {
			return qName;
		} else {
			return name;
		}
	}

	class MyDefaultHandler extends DefaultHandler {

		private StringBuffer buf;
		private Book mBook;

		public MyDefaultHandler() {
			super();
			mBook = new Book();
		}

		protected StringBuffer getBuffer() {
			return this.buf;
		}

		@Override
		public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
			super.startElement(uri, localName, qName, attributes);
			buf = new StringBuffer();
			for (int i = 0; i < attributes.getLength(); i++) {
				String value = attributes.getValue(i);
				mBook.email = value;
			}

		}

		@Override
		public void characters(char[] chars, int start, int length) throws SAXException {
			super.characters(chars, start, length);
			getBuffer().append(chars, start, length);
		}

		@Override
		public void endElement(String uri, String localName, String qName) throws SAXException {
			super.endElement(uri, localName, qName);
			String elementName = getElementName(localName, qName);
			if (elementName.equals("book")) {
				list.add(mBook);
				mBook = new Book();
			} else if (elementName.equals("name")) {
				mBook.name = getBuffer().toString();
			} else if (elementName.equals("price")) {
				mBook.price = getBuffer().toString();
			}

		}

	}

	private ArrayList<Book> list = new ArrayList<Book>();

	private class Book {
		String email;
		String name;
		String price;

		@Override
		public String toString() {
			return "name=" + name + "price=" + price;
		}

	}

Das Obige zeigt, wie Android DOM und SAXParserFactory verwendet Um den Inhalt der XML-Datei zu analysieren, beachten Sie bitte die chinesische PHP-Website (www.php.cn)!



Stellungnahme:
Der Inhalt dieses Artikels wird freiwillig von Internetnutzern beigesteuert und das Urheberrecht liegt beim ursprünglichen Autor. Diese Website übernimmt keine entsprechende rechtliche Verantwortung. Wenn Sie Inhalte finden, bei denen der Verdacht eines Plagiats oder einer Rechtsverletzung besteht, wenden Sie sich bitte an admin@php.cn