sax dom dom4j 去解析一个xml,dom4j去构建家族的xml,将cd.xml封装对象，并且将所有的对象存储起来到一个文件

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1.sax dom dom4j 去解析一个xml

要求的xml

<?xml version="1.0" encoding="utf-8"?>
<!--这是一个神奇的宇宙 -->
<human>
	<person num="0001">
		<name>卢凯奇</name>
		<age>18</age>
		<work>学生</work>
		<skill>无敌</skill>
		<desc>永远年轻，human宇宙001号选手</desc>
	</person>
	<person num="0002">
		<name>白展堂</name>
		<age>18</age>
		<work>跑堂的</work>
		<skill>葵花点穴手</skill>
		<desc>盗圣</desc>
	</person>
	<person num="0003">
		<name>佟湘玉</name>
		<age>18</age>
		<work>展柜的</work>
		<skill>移魂大法</skill>
		<desc>曾经的什么什么堂堂主</desc>
	</person>
	<person num="0004">
		<name>李大嘴</name>
		<age>18</age>
		<work>烧菜的</work>
		<skill>降龙十巴掌</skill>
		<desc>做的饭很咸，师傅是御膳房总管，先帝是被他师傅活活齁死的</desc>
	</person>			
</human>

1.1 sax代码

@Test
	public void SAXtest() throws Exception {
		// 工厂
		SAXParserFactory factory = SAXParserFactory.newInstance();
		// 解析器
		SAXParser newSAXParser = factory.newSAXParser();
		newSAXParser.parse("src/person.xml", new DefaultHandler() {
			@Override
			public void startDocument() throws SAXException {
				// TODO Auto-generated method stub
				System.out.println("开始解析");
				System.out.println("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
			}

			@Override
			public void startElement(String uri, String localName, String qName, Attributes attributes)
					throws SAXException {
				System.out.print("<" + qName);
				for (int i = 0; i < attributes.getLength(); i++) {
					System.out.print(" "+attributes.getQName(i) + "=\"" + attributes.getValue(i) + "\">");
				}
				if (attributes.getLength() == 0)
				{
					System.out.print(">");
				}
			}

			@Override
			public void characters(char[] ch, int start, int length) throws SAXException {
				String str= new String(ch,start,length);
					System.out.print(str);
			}
			@Override
			public void endElement(String uri, String localName, String qName) throws SAXException {
				System.out.println("/<"+qName+">");
			}
			@Override
			public void endDocument() throws SAXException {
				System.out.println("结束解析");
			}
		});

1.2 dom 代码

@Test
	public void domAnalysis() throws Exception {
		DocumentBuilderFactory Factory = DocumentBuilderFactory.newInstance();
		DocumentBuilder newDocumentBuilder = Factory.newDocumentBuilder();
		// 文档对象 用来表示被解析的xml
		Document document = newDocumentBuilder.parse(new File("src/person.xml"));
		System.out.println("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
		print(document);
	}

		//都继承了node
	public void print(Node node) {
		if (node == null) {
			System.out.println("节点为空");
		}
		switch (node.getNodeType()) {
		case Node.DOCUMENT_NODE:
			// 先把node 转回来
			Document document = (Document) node;
			// 获得根节点
			Element element = document.getDocumentElement();
			print(element);
			break;
		case Node.ELEMENT_NODE:
			Element childElement = (Element) node;
			System.out.print("<" + childElement.getTagName());
			NamedNodeMap attributes = childElement.getAttributes();
				for (int i = 0; i < attributes.getLength(); i++) {
					print(attributes.item(i));
				}
			if(attributes.getLength()==0) {
				System.out.print(">");
			}
			// 子节点
			NodeList childNodes = node.getChildNodes();
			for (int i = 0; i < childNodes.getLength(); i++) {
				print(childNodes.item(i));
			}
			System.out.print("</" + childElement.getTagName() + ">");
			break;
		case Node.TEXT_NODE:
			System.out.print(node.getTextContent());
			break;
		case Node.ATTRIBUTE_NODE:
			Attr attr = (Attr) node;
			System.out.print(" " + attr.getName() + "=\"" + attr.getValue() + "\">");
			break;
		case Node.COMMENT_NODE:
			System.out.println("-------------------------");
			break;
		default:
			throw new RuntimeException("解析到意外的节点");
		}
	}

1.3 dom4j代码

@Test
	public void Dom4j() throws Exception {
		SAXReader saxReader = new SAXReader();
		Document document = saxReader.read("src/cd.xml");
		//根标签
		Element element = document.getRootElement();
		//根标签的子标签
		List<Element> list = element.elements();
		list.forEach((t)->{
			//标签名
			System.out.print("  "+"<"+t.getName());
			List<Attribute> list2 = t.attributes();
			list2.forEach((p)->{
				//属性
				System.out.println(" "+p.getName()+"=\""+p.getValue()+"\">");
			});
			List<Element> list3 = t.elements();			
//			System.out.println("------------------------------");
//			System.out.println(list3.get(0).getName()+list3.get(0).getText());
//			System.out.println("-------------------------------");
			list3.forEach(l->{
				//获取不带空格的文本
//				System.out.println(l.getTextTrim());
				System.out.print("\t"+"<"+l.getName()+">");
				System.out.print(l.getText());
				System.out.println("<"+l.getName()+">");
			});
			System.out.println("</"+t.getName()+">");
		});
		
	}

2.dom4j去构建家族的xml

要求的xml

	<ancestors>
		<father id="1234567890">
			<name>李四</name>
			<salary>1231.11</salary>
		<father>
		<son id="ssss">
			<name>李四1</name>
			<salary>1221.11</salary>
		<son>
	</ancestors>

2.1代码

public static void main(String[] args) throws Exception {

		Document document = DocumentHelper.createDocument();
		// 等到一个根节点
		Element element = document.addElement("ancestors");
		Element attribute = element.addElement("father").addAttribute("id", "1234567890");
		attribute.addElement("name").addText("tom");
		attribute.addElement("salary").addText("2000");
		Element attribute2 = element.addElement("son").addAttribute("id", "1234567891");
		attribute2.addElement("naem").addText("sala");
		attribute2.addElement("salary").addText("2100");
		OutputFormat format = new OutputFormat();
		//编码
		format.setEncoding("utf-8");
		//换行
		format.setNewlines(true);
		//缩进
		format.setIndent(true);
		//打印出去
		XMLWriter writer = new XMLWriter(new PrintWriter("src/work2.xml"),format);
		//把根节点写进去
		writer.write(document);
		writer.flush();
		writer.close();
	}

3.将cd.xml封装对象，并且将所有的对象存储起来到一个文件

要求的xml

<?xml version="1.0" encoding="UTF-8"?>
<cds>
	<cd id="x112">
		<name>周杰伦</name>
		<price>155.5</price>
		<title>七里香</title>
	</cd>
	<cd id="x113">
		<name>林俊杰</name>
		<price>156.1</price>
		<title>江南</title>
	</cd>
	<cd id="x114">
		<name>蔡依林</name>
		<price>155.65</price>
		<title>呸</title>
	</cd>
	<cd id="x115">
		<name>蔡徐坤</name>
		<price>15.61</price>
		<title>篮球</title>
	</cd>
	<cd id="x116">
		<name>毛不易</name>
		<price>156.1</price>
		<title>入海</title>
	</cd>
</cds>

3.1代码

public static void main(String[] args) throws Exception {
		SAXReader saxReader = new SAXReader();
		Document read = saxReader.read("src/cd.xml");
		//根节点
		Element element = read.getRootElement();
		//根节点的子节点
		List<Element> elements = element.elements();
		  ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("src/cd.txt"));
		elements.forEach(t->{
				Person person = new Person();
				List<Attribute> attributes = t.attributes();
				attributes.forEach(p->{
					person.setId(p.getValue());
				});
				List<Element> list = t.elements();
				  person.setName(list.get(0).getText());
				  person.setPrice(list.get(1).getText());
				  person.setTitle(list.get(2).getText());
				try {
					oos.writeObject(person);
					oos.flush();
				} catch (IOException e) {
					e.printStackTrace();
				}
		});
		oos.close();
	}