[Java] 寫入及讀取 XML 檔案

[Java] 寫入及讀取 XML 檔案

這邊記錄兩種方式
一種是 DocumentBuilder 的方式,一種是使用第三方 Lib JAXB的方式

	@XmlRootElement(name = "centerInfo")
	@XmlAccessorType(XmlAccessType.FIELD)
	public class CenterInfo extends BaseXmlConfig {
	@XmlAttribute(name = "Id")
	private String id;
	@XmlAttribute(name = "Name")
	private String name;
	@XmlAttribute(name = "status")
	private String status;
	public String getId() {
	return id;
	}
	public void setId(String id) {
	this.id = id;
	}
	public String getName() {
	return name;
	}
	public void setName(String name) {
	this.name = name;
	}
	public String getStatus() {
	return status;
	}
	public void setStatus(String status) {
	this.status = status;
	}
	}

view raw CenterInfo.java hosted with ❤ by GitHub

	@XmlRootElement(name = "centerList")
	@XmlAccessorType(XmlAccessType.FIELD)
	public class CenterList extends BaseXmlConfig {
	@XmlElement(name = "centerInfo")
	private List<CenterInfo> centerInfo;
	public List<CenterInfo> getCenterInfo() {
	return centerInfo;
	}
	public void setCenterInfo(List<CenterInfo> centerInfo) {
	this.centerInfo = centerInfo;
	}
	}

view raw CenterList.java hosted with ❤ by GitHub

	/**
	* https://www.mkyong.com/java/how-to-create-xml-file-in-java-dom/
	*/
	@Test
	public void testWriteXmlUseDocument() {
	final String ROOT_ELEMENT = "centerList";
	final String CHILDREN_ELEMENT = "centerInfo";
	final String ID = "Id";
	final String NAME = "Name";
	final String STATUS = "status";
	try {
	DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
	DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
	// root element
	Document doc = docBuilder.newDocument();
	Element rootElement = doc.createElement(ROOT_ELEMENT);
	doc.appendChild(rootElement);
	// centerInfo elements
	Element centerInfo = doc.createElement(CHILDREN_ELEMENT);
	rootElement.appendChild(centerInfo);
	Element centerInfo2 = doc.createElement(CHILDREN_ELEMENT);
	rootElement.appendChild(centerInfo2);
	Attr attrId = doc.createAttribute(ID);
	attrId.setValue("777");
	centerInfo.setAttributeNode(attrId);
	Attr attrName = doc.createAttribute(NAME);
	attrName.setValue("測試");
	centerInfo.setAttributeNode(attrName);
	Attr attrStatus = doc.createAttribute(STATUS);
	attrStatus.setValue("0");
	centerInfo.setAttributeNode(attrStatus);
	Attr attrId2 = doc.createAttribute(ID);
	attrId2.setValue("6000");
	centerInfo2.setAttributeNode(attrId2);
	Attr attrName2 = doc.createAttribute(NAME);
	attrName2.setValue("測試二");
	centerInfo2.setAttributeNode(attrName2);
	Attr attrStatus2 = doc.createAttribute(STATUS);
	attrStatus2.setValue("1");
	centerInfo2.setAttributeNode(attrStatus2);
	// write the content into xml file
	TransformerFactory transformerFactory = TransformerFactory.newInstance();
	Transformer transformer = transformerFactory.newTransformer();
	DOMSource source = new DOMSource(doc);
	StreamResult result = new StreamResult(new File("test.xml"));
	transformer.transform(source, result);
	Assert.assertNotNull(result);
	} catch (ParserConfigurationException | TransformerException e) {
	e.printStackTrace();
	}
	}

view raw xmlWriterTest001.java hosted with ❤ by GitHub

	private CenterList centerList;
	private CenterInfo centerInfo;
	private CenterInfo centerInfo2;
	private List<CenterInfo> centerInfos;
	@Before
	public void setUp() {
	prepareCenterConfig();
	}
	/**
	* http://www.journaldev.com/1234/jaxb-example-tutorial
	* http://blog.bdoughan.com/2011/06/jaxb-and-complex-types-with-simple.html
	*/
	@Test
	public void testWriteXmlUseJaxb() {
	centerList.setCenterInfo(centerInfos);
	jaxbObjectToXML(centerList);
	CenterList centerList1 = jaxbXMLToObject();
	Assert.assertNotNull(centerList1);
	}
	private void jaxbObjectToXML(CenterList centerList) {
	try {
	JAXBContext context = JAXBContext.newInstance(CenterList.class);
	Marshaller m = context.createMarshaller();
	m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
	m.marshal(centerList, new File("test.xml"));
	} catch (JAXBException e) {
	e.printStackTrace();
	}
	}
	private CenterList jaxbXMLToObject() {
	try {
	JAXBContext context = JAXBContext.newInstance(CenterList.class);
	Unmarshaller un = context.createUnmarshaller();
	CenterList centerList = (CenterList) un.unmarshal(new File("test.xml"));
	return centerList;
	} catch (JAXBException e) {
	e.printStackTrace();
	}
	return null;
	}
	private void prepareCenterConfig() {
	centerList = new CenterList();
	centerInfo = new CenterInfo();
	centerInfo.setId("777");
	centerInfo.setName("測試");
	centerInfo.setStatus("1");
	centerInfo2 = new CenterInfo();
	centerInfo2.setId("7778");
	centerInfo2.setName("測試2");
	centerInfo2.setStatus("0");
	centerInfos = new ArrayList<>();
	centerInfos.add(centerInfo);
	centerInfos.add(centerInfo2);
	centerList.setCenterInfo(centerInfos);
	}

view raw xmlWriterTest002.java hosted with ❤ by GitHub