import org.w3c.dom.Element;
import org.w3c.dom.Text;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Attr;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.util.Properties;
import java.io.FileOutputStream;
import java.io.File;
public class WriteRead ... {
public WriteRead() ...{
}
String FILE_NAME = "my.xml";
public void CreateXMLFile() throws Exception ...{
//生成Document
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder dbr = dbf.newDocumentBuilder();
Document doc = dbr.newDocument();
//添加内容
//根节点:
Element root = doc.createElement("Root");
root.setAttribute("att1", "Hello");
root.setAttribute("att2", "World");
Text rootText = doc.createTextNode("RootDate");
root.appendChild(rootText);
doc.appendChild(root);
//子节点:
Element child = doc.createElement("Child");
child.setAttribute("att1", "Hello");
child.setAttribute("att2", "Earth");
Text childText = doc.createTextNode("ChildDate");
child.appendChild(childText);
root.appendChild(child);
//孙子节点:
Element grandchild = doc.createElement("GrandChild");
grandchild.setAttribute("att1", "Hello");
grandchild.setAttribute("att2", "Lover");
Text grandchildText = doc.createTextNode("GrandChildDate");
grandchild.appendChild(grandchildText);
child.appendChild(grandchild);
//生成文件
TransformerFactory tff = TransformerFactory.newInstance();
Transformer tfr = tff.newTransformer();
Properties pts = tfr.getOutputProperties();
pts.setProperty(OutputKeys.ENCODING, "GBK");
tfr.setOutputProperties(pts);
tfr.transform(new DOMSource(doc),
new StreamResult(new FileOutputStream(FILE_NAME, false)));
}
public void ReadXMLFile() throws Exception ...{
//读取XML文件
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder dbr = dbf.newDocumentBuilder();
File file = new File(FILE_NAME);
Document doc = dbr.parse(file);
Element root = doc.getDocumentElement();
//顺序读取所有节点及属性
System.out.println("The root element is:" + root.getNodeName());
NodeList children = root.getChildNodes();
System.out.println("There are " + children.getLength() +
" nodes in this document.");
System.out.println("**********");
for (Node child = root.getFirstChild(); child != null;
child = child.getNextSibling()) ...{
System.out.println(child.getNodeName() + " = " +
child.getNodeValue());
}
System.out.println("**********");
StepThrough(root);
System.out.println("**********");
StepThroughAll(root);
//读取指定节点的值
System.out.println("**********");
NodeList nl = root.getElementsByTagName("GrandChild");
System.out.println(nl.item(0).getFirstChild().getNodeValue());
//读取指定节点的属性值
System.out.println("**********");
NodeList n2 = root.getElementsByTagName("Child");
Element el2 = (Element)n2.item(0);
Attr attr = el2.getAttributeNode("att2");
System.out.println(attr.getValue());
}
private void StepThrough(Node start) ...{
System.out.println(start.getNodeName() + " = " + start.getNodeValue());
for (Node child = start.getFirstChild(); child != null;
child = child.getNextSibling()) ...{
StepThrough(child);
}
}
private void StepThroughAll(Node start) ...{
System.out.println(start.getNodeName() + " = " + start.getNodeValue());
if (start.getNodeType() == Node.ELEMENT_NODE) ...{
NamedNodeMap startAtt = start.getAttributes();
for (int i = 0, len = startAtt.getLength(); i < len; i++) ...{
Node attr = startAtt.item(i);
System.out.println(" Attribute: " + attr.getNodeName() + " = " +
attr.getNodeValue());
}
}
for (Node child = start.getFirstChild(); child != null;
child = child.getNextSibling()) ...{
StepThroughAll(child);
}
}
public static void main(String[] args) ...{
WriteRead writeread = new WriteRead();
try ...{
writeread.CreateXMLFile();
} catch (Exception e) ...{
e.printStackTrace();
}
try ...{
writeread.ReadXMLFile();
} catch (Exception e) ...{
e.printStackTrace();
}
}
} 运行结果:
生成文件: <?xml version="1.0" encoding="GBK"?><Root att1="Hello" att2="World">RootDate<Child att1="Hello" att2="Earth">ChildDate<GrandChild att1="Hello" att2="Lover">GrandChildDate</GrandChild></Child></Root>
打印结果:
The root element is:Root
There are 2 nodes in this document.
**********
#text = RootDate
Child = null
**********
Root = null
#text = RootDate
Child = null
#text = ChildDate
GrandChild = null
#text = GrandChildDate
**********
Root = null
Attribute: att1 = Hello
Attribute: att2 = World
#text = RootDate
Child = null
Attribute: att1 = Hello
Attribute: att2 = Earth
#text = ChildDate
GrandChild = null
Attribute: att1 = Hello
Attribute: att2 = Lover
#text = GrandChildDate
**********
GrandChildDate
**********
Earth DOM模型:
org.w3c.dom
- interface org.w3c.dom.DOMImplementation
- interface org.w3c.dom.NamedNodeMap
-
interface org.w3c.dom.Node
- interface org.w3c.dom.Attr
- interface org.w3c.dom.CharacterData
- interface org.w3c.dom.CDATASection
- interface org.w3c.dom.Document
- interface org.w3c.dom.DocumentFragment
- interface org.w3c.dom.DocumentType
- interface org.w3c.dom.Element
- interface org.w3c.dom.Entity
- interface org.w3c.dom.EntityReference
- interface org.w3c.dom.Notation
- interface org.w3c.dom.ProcessingInstruction
- interface org.w3c.dom.NodeList