package demo;

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

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
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;
import org.w3c.dom.Node;
import org.xml.sax.SAXException;

public class xmlTest {
	public static void main(String[] args) {
		//调用 DocumentBuilderFactory.newInstance() 方法得到创建 DOM 解析器的工厂 
		DocumentBuilderFactory factory=DocumentBuilderFactory.newInstance();
        Element theBook=null, theElem=null, root=null;
        try {
            factory.setIgnoringElementContentWhitespace(true);//是否删除空格  false true
            DocumentBuilder db=factory.newDocumentBuilder();  //获取解析器
            //指定路径 获取xml文件的document对象
            File f = new File("src/book.xml"); 
            Document xmldoc=db.parse(f);
            root=xmldoc.getDocumentElement();
            //添加 元素(节点)
            theBook=xmldoc.createElement("book1");
            theElem=xmldoc.createElement("name");
            theElem.setTextContent("平凡的世界");
            theBook.appendChild(theElem);
            
            theElem=xmldoc.createElement("price");
            theElem.setTextContent("￥55.0");
            theBook.appendChild(theElem);

            theElem=xmldoc.createElement("conment");
            theElem.setTextContent("推荐大家看看这本书");
            theBook.appendChild(theElem);
            root.appendChild(theBook);
            
            printXML(xmldoc);				//打印至Console
            saveXml("new_book.xml", xmldoc);//保存生成 xml文件
        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        } catch (SAXException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
	}
	
	/**
	 * 将node的XML字符串打印到控制台
	 * @param node
	 */
	public static void printXML(Node node) {
        TransformerFactory transFactory=TransformerFactory.newInstance();
        try {
            Transformer transformer = transFactory.newTransformer();
            transformer.setOutputProperty("encoding", "gb2312");//指定编码
            transformer.setOutputProperty("indent", "yes");     //是否设置缩进

            DOMSource source=new DOMSource();
            source.setNode(node);
            StreamResult result=new StreamResult();
            result.setOutputStream(System.out);
            
            transformer.transform(source, result);
        } catch (TransformerConfigurationException e) {
            e.printStackTrace();
        } catch (TransformerException e) {
            e.printStackTrace();
        }   
    }
 
	/**
	 * 保存生成xml文件
	 * @param fileName
	 * @param doc
	 */
    public static void saveXml(String fileName, Document doc) {//将Document输出到文件
        TransformerFactory transFactory=TransformerFactory.newInstance();
        try {
            Transformer transformer = transFactory.newTransformer();
            transformer.setOutputProperty("indent", "yes");//是否设置缩进

            DOMSource source=new DOMSource();
            source.setNode(doc);
            StreamResult result=new StreamResult();
            result.setOutputStream(new FileOutputStream(fileName));
            
            transformer.transform(source, result);
        } catch (TransformerConfigurationException e) {
            e.printStackTrace();
        } catch (TransformerException e) {
            e.printStackTrace();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }   
    }
}