java基础笔记（6）

xml文件的写入

通过dom生成xml文件：

package com.writexml;

import java.io.File;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.*;

import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class domWrite {
    public DocumentBuilder getDocumentBuilder() throws ParserConfigurationException {
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        DocumentBuilder db = dbf.newDocumentBuilder();
        return db;
    }
    public void creatXML() throws ParserConfigurationException, TransformerException {
        DocumentBuilder db = getDocumentBuilder();
        Document document = db.newDocument();
        document.setXmlStandalone(true);//默认的话会在生成的xml文件声明中将Standalone=“no”，这样会生成说明格式的文档，若要将其不生成，这通过这个语句设置成yes，即true
        Element bookstore = document.createElement("bookstore");//创建节点
        Element book = document.createElement("book");
        Element name = document.createElement("name");
        name.setTextContent("童话故事");
        book.setAttribute("id", "1");
        document.appendChild(bookstore);//将bookstore根节点增加到dom树中
        bookstore.appendChild(book);//将book节点增加到bookstore根节点中
        book.appendChild(name);
        TransformerFactory tff = TransformerFactory.newInstance();//创建TransformerFactory对象
        Transformer tf = tff.newTransformer();//创建Transformer对象
        tf.setOutputProperty(OutputKeys.INDENT, "yes");//是否换行
        tf.transform(new DOMSource(document), new StreamResult(new File("books01.xml")));//将document输入到文件中

    }
    public static void main(String[] args) throws ParserConfigurationException, TransformerException {
        // TODO Auto-generated method stub
        domWrite test = new domWrite();
        test.creatXML();
    }

}

通过SAX生成xml文件：

package com.writexml;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.sax.SAXTransformerFactory;
import javax.xml.transform.sax.TransformerHandler;
import javax.xml.transform.stream.StreamResult;

import org.jdom2.Attribute;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;

import com.entry.Book;
import com.hd.SAXHd;

public class saxWrite {
    public ArrayList<Book> parseXml() throws ParserConfigurationException, SAXException, IOException{
        SAXParserFactory factory = SAXParserFactory.newInstance();
        SAXParser parser = factory.newSAXParser();
        SAXHd hd = new SAXHd();
        parser.parse("books.xml", hd);
        return hd.getBookList();
    }
    public void creatXML() throws ParserConfigurationException, SAXException, IOException, TransformerConfigurationException {
        ArrayList<Book> book = parseXml();//运行parseXml，将一个包含两本书对象的集合传给变量book；
        SAXTransformerFactory tff = (SAXTransformerFactory)SAXTransformerFactory.newInstance();//创建SAXTransformerFactory对象
        TransformerHandler tfh = tff.newTransformerHandler();//创建TransformerHandler对象；
        Transformer tf = tfh.getTransformer();//通过TransformerHandler创建Transformer对象；
        tf.setOutputProperty(OutputKeys.ENCODING, "UTF-8");//通过Transformer对象设置编码；
        tf.setOutputProperty(OutputKeys.INDENT, "YES");//通过Transformer对象设置是否换行；
        File f = new File("books02.xml");
        if(!f.exists()) {
            f.createNewFile();
        }
        Result result = new StreamResult(new FileOutputStream(f));//将文件加载到result中
        tfh.setResult(result);//将创建好的result对象和TransformerHandler对象关联
        tfh.startDocument();//打开文档
        AttributesImpl attr = new AttributesImpl();
        tfh.startElement("", "", "bookstore", attr);
        for (Book i :book) {
        attr.clear();
        attr.addAttribute("", "", "id", "", i.getId());
        tfh.startElement("","","book",attr);
        if(i.getName()!=null && !i.getName().trim().equals("")) {
        attr.clear();
        tfh.startElement("","","name",attr);
        tfh.characters(i.getName().toCharArray(), 0, i.getName().length());
        tfh.endElement("","","name");}
        if(i.getAuthor()!=null && !i.getAuthor().trim().equals("")) {
        attr.clear();
        tfh.startElement("","","author",attr);
        tfh.characters(i.getAuthor().toCharArray(), 0, i.getAuthor().length());
        tfh.endElement("","","author");}
        if(i.getYear()!=null && !i.getYear().trim().equals("")) {
        attr.clear();
        tfh.startElement("","","year",attr);
        tfh.characters(i.getYear().toCharArray(), 0, i.getYear().length());
        tfh.endElement("","","year");}
        tfh.endElement("","","book");
        }
        tfh.endElement("", "", "bookstore");

        tfh.endDocument();//关闭文档

    }
    public static void main(String[] args) throws TransformerConfigurationException, ParserConfigurationException, SAXException, IOException {
        // TODO Auto-generated method stub
        saxWrite test = new saxWrite();
        test.creatXML();
    }

}

dom4j创建rss类的xml文件：

package com.writexml;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import org.dom4j.Document;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.XMLWriter;

public class dom4j {
    public void creatMXL() throws IOException {
        Document document = DocumentHelper.createDocument();//创建document对象，代表整个xml文档
        Element rss = document.addElement("rss");//创建根节点rss；
        rss.addAttribute("version", "2.0");//向根节点添加属性
        Element channel = rss.addElement("channel");//生成rss的子节点channel
        Element title = channel.addElement("title");//生成channel的子节点title
        title.setText("国内最新新闻");//设置子节点title的节点值
        OutputFormat format = OutputFormat.createPrettyPrint();//设置格式
        format.setEncoding("GBK");//设置字符编码
        File file = new File("books03.xml");
        XMLWriter writer = new XMLWriter(new FileOutputStream(file),format);
        writer.setEscapeText(false);//设置是否转义，默认是会转义
        writer.write(document);//生成xml文件并传进格式
        writer.close();
    }

    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
        dom4j test = new dom4j();
        test.creatMXL();
    }

}

JDOM生成xml文件

package com.writexml;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.output.EscapeStrategy;
import org.jdom2.output.Format;
import org.jdom2.output.XMLOutputter;

public class jdomWriter {
     EscapeStrategy es = new EscapeStrategy() {

        @Override
        public boolean shouldEscape(char arg0) {
            // TODO Auto-generated method stub
            return false;
        }
    };
    public void creatXML() throws FileNotFoundException, IOException {
        Element rss = new Element("rss");//创建rss根节点
        rss.setAttribute("servion", "2.0");//创建节点的属性
        Document document = new Document(rss);//生成document对象，并将根节点传入
        Element channel = new Element("channel");
        rss.addContent(channel);
        Element title = new Element("title");
        title.setText("国内最新新闻");
        channel.addContent(title);
        Format format = Format.getPrettyFormat();
        format.setEscapeStrategy(es );
        XMLOutputter outputer = new XMLOutputter(format);//创建outputer对象
        File file = new File("books04.xml");
        outputer.output(document, new FileOutputStream(file));//通过outputer对象中的output方法将document对象传入xml文件中

    }
    public static void main(String[] args) throws FileNotFoundException, IOException {
        // TODO Auto-generated method stub
        jdomWriter test = new jdomWriter();
        test.creatXML();
    }

}