第一百八十六节 Java XML教程 - Java DOM编辑

Java XML教程 - Java DOM编辑

属性

以下代码显示如何向元素添加属性。

import java.io.StringWriter;  import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.transform.OutputKeys; import javax.xml.transform.Transformer; import javax.xml.transform.TransformerFactory; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult;  import org.w3c.dom.DOMImplementation; import org.w3c.dom.Document; import org.w3c.dom.Element;  public class Main {   public static void main(String[] argv) throws Exception {     DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();     DocumentBuilder builder = factory.newDocumentBuilder();     DOMImplementation impl = builder.getDOMImplementation();     Document doc = impl.createDocument(null, null, null);     Element e1 = doc.createElement("api");     doc.appendChild(e1);     Element e2 = doc.createElement("java");     e1.appendChild(e2);          e2.setAttribute("url", "http://www.www.w3cschool.cn");          //transform the DOM for showing the result in console     DOMSource domSource = new DOMSource(doc);     Transformer transformer = TransformerFactory.newInstance().newTransformer();     transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");     transformer.setOutputProperty(OutputKeys.METHOD, "xml");     transformer.setOutputProperty(OutputKeys.ENCODING, "ISO-8859-1");     transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");     transformer.setOutputProperty(OutputKeys.INDENT, "yes");     StringWriter sw = new StringWriter();     StreamResult sr = new StreamResult(sw);     transformer.transform(domSource, sr);     System.out.println(sw.toString());   } } 

上面的代码生成以下结果。

复制属性

    public void dupAttributes(Document doc) {         Element root = doc.getDocumentElement();         Element personOne = (Element)root.getFirstChild();         Element personTwo = (Element)personOne.getNextSibling();         Element personThree = (Element)personTwo.getNextSibling();          Attr deptAttr = personOne.getAttributeNode("dept");         personOne.removeAttributeNode(deptAttr);         String deptString = deptAttr.getValue();         personTwo.setAttribute("dept",deptString);         personThree.setAttribute("dept",deptString);          String mailString = personOne.getAttribute("mail");         personTwo.setAttribute("mail",mailString);                  String titleString = personOne.getAttribute("title");         personOne.removeAttribute("title");         personThree.setAttribute("title",titleString);     } 

删除两个属性

    public void delAttribute(Document doc) {         Element root = doc.getDocumentElement();         Element person = (Element)root.getFirstChild();         person.removeAttribute("extension");         person.removeAttribute("dept");     } 

元素

import java.io.StringWriter;  import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.transform.OutputKeys; import javax.xml.transform.Transformer; import javax.xml.transform.TransformerFactory; import javax.xml.transform.dom.DOMSource; import javax.xml.transform.stream.StreamResult;  import org.w3c.dom.DOMImplementation; import org.w3c.dom.Document; import org.w3c.dom.Node;  public class Main {   public static void main(String[] argv) throws Exception {     DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();     DocumentBuilder builder = factory.newDocumentBuilder();     DOMImplementation impl = builder.getDOMImplementation();     Document doc = impl.createDocument(null, null, null);      Node root = doc.createElement("A");     doc.appendChild(root);      Node stanza = doc.createElement("B");     root.appendChild(stanza);      Node line = doc.createElement("C");     stanza.appendChild(line);     line.appendChild(doc.createTextNode("test"));     line = doc.createElement("Line");     stanza.appendChild(line);     line.appendChild(doc.createTextNode("test"));          //transform the DOM for showing the result in console     DOMSource domSource = new DOMSource(doc);     Transformer transformer = TransformerFactory.newInstance().newTransformer();     transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");     transformer.setOutputProperty(OutputKeys.METHOD, "xml");     transformer.setOutputProperty(OutputKeys.ENCODING, "ISO-8859-1");     transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");     transformer.setOutputProperty(OutputKeys.INDENT, "yes");     StringWriter sw = new StringWriter();     StreamResult sr = new StreamResult(sw);     transformer.transform(domSource, sr);     System.out.println(sw.toString());   } } 

上面的代码生成以下结果。

以下代码显示如何从父代删除元素。

    public void deleteFirstElement(Document doc) {         Element root = doc.getDocumentElement();         Element child = (Element)root.getFirstChild();         root.removeChild(child);     }           

文本节点

以下代码显示如何向元素添加文本节点。

import java.io.StringWriter;  import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory;  import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.bootstrap.DOMImplementationRegistry; import org.w3c.dom.ls.DOMImplementationLS; import org.w3c.dom.ls.LSOutput; import org.w3c.dom.ls.LSSerializer;  public class Main {    public static void main(String[] argv) throws Exception {     DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();     dbf.setNamespaceAware(true);     DocumentBuilder db = dbf.newDocumentBuilder();     Document doc = db.newDocument();      Element root = doc.createElementNS(null, "person"); // Create Root Element     Element item = doc.createElementNS(null, "name"); // Create element     item.appendChild(doc.createTextNode("Jeff"));     root.appendChild(item); // Attach element to Root element     item = doc.createElementNS(null, "age"); // Create another Element     item.appendChild(doc.createTextNode("28"));     root.appendChild(item); // Attach Element to previous element down tree     item = doc.createElementNS(null, "height");     item.appendChild(doc.createTextNode("1.80"));     root.appendChild(item); // Attach another Element - grandaugther     doc.appendChild(root); // Add Root to Document      DOMImplementationRegistry registry = DOMImplementationRegistry         .newInstance();     DOMImplementationLS domImplLS = (DOMImplementationLS) registry         .getDOMImplementation("LS");      LSSerializer ser = domImplLS.createLSSerializer(); // Create a serializer                                                        // for the DOM     LSOutput out = domImplLS.createLSOutput();     StringWriter stringOut = new StringWriter(); // Writer will be a String     out.setCharacterStream(stringOut);     ser.write(doc, out); // Serialize the DOM      System.out.println("STRXML = " + stringOut.toString()); // DOM as a String   } } 

上面的代码生成以下结果。

以下代码显示了如何通过插入和替换编辑文本。

    public void edit3(Document doc) {         int count;         int offset;          Element root = doc.getDocumentElement();         Element place = (Element)root.getFirstChild();         Text name = (Text)place.getFirstChild().getFirstChild();         Text directions = (Text)place.getLastChild().getFirstChild();          offset = 7;         name.insertData(offset," black");          offset = 5;         count = 4;         directions.replaceData(offset,count,"right");     } 

通过剪切和粘贴修改文本

    public void edit(Document doc) {         int length;         int count;         int offset;          Element root = doc.getDocumentElement();         Element place = (Element)root.getFirstChild();         Text name = (Text)place.getFirstChild().getFirstChild();         Text directions = (Text)place.getLastChild().getFirstChild();          length = name.getLength();         count = 4;         offset = length - 4;         name.deleteData(offset,count);          length = directions.getLength();         count = 6;         offset = length - count;         String bridge = directions.substringData(offset,count);          name.appendData(bridge);          count = 5;         offset = 4;         directions.deleteData(offset,count);     }  

通过替换修改文本

    public void edit(Document doc) {         Element root = doc.getDocumentElement();         Element place = (Element)root.getFirstChild();         Text name = (Text)place.getFirstChild().getFirstChild();         Text directions = (Text)place.getLastChild().getFirstChild();          name.setData("AAA");         directions.setData("BBB");     } 

注释

以下代码显示如何为XML创建注释节点。

import java.io.File;  import javax.xml.parsers.DocumentBuilderFactory;  import org.w3c.dom.Comment; import org.w3c.dom.Document; import org.w3c.dom.Element;  public class Main {   public static void main(String[] argv) throws Exception {      DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();     factory.setValidating(true);      factory.setExpandEntityReferences(false);      Document doc = factory.newDocumentBuilder().parse(new File("filename"));      Element element = doc.getDocumentElement();     Comment comment = doc.createComment("A Document Comment");     element.getParentNode().insertBefore(comment, element);    } } 

处理指令

下面的代码显示了如何添加ProcessingInstruction。

    public void addProcessingInstruction(Document doc) {         Element root = doc.getDocumentElement();         Element folks = (Element)root.getLastChild();         ProcessingInstruction pi;         pi = (ProcessingInstruction)doc.createProcessingInstruction(             "validate",             "phone=\"lookup\"");         root.insertBefore(pi,folks);     } 

CDATA

以下代码显示如何添加CDATA到XML文档。

    public void addCDATA(Document doc) {         Element root = doc.getDocumentElement();         Element place = (Element)root.getFirstChild();         Element directions = (Element)place.getLastChild();         String dirtext =             ">>>\n" +             "<<<\n" +             "&&&\n" +             "<><><>.";         CDATASection dirdata = doc.createCDATASection(dirtext);         directions.replaceChild(dirdata,directions.getFirstChild());     }      

克隆

    public void duplicatePerson(Document doc) {         Element root = doc.getDocumentElement();         Element origPerson = (Element)root.getFirstChild();         Element newPerson = (Element)origPerson.cloneNode(true);         root.appendChild(newPerson);     }