在前面的教程中，我们学习了使用DOM解析方式读取和修改XML文件内容，今天我们来学习如何使用DOM解析机制生成XML文件。
下面是我们对要生成的XML文件的具体要求：
1.根节点元素为”Employees”,命名空间为”//m.sbmmt.com/“,根节点下包含一系列的Employee元素。
2.员工的信息通过Employee节点表示，生成的XML文件有两条员工的信息。
3.每个员工有个”id”属性。
4.Employee 元素有四个子元素- “name”, “age”, “role”, “gender”。
下面是程序代码：
package com.journaldev.xml;
import java.io.File;
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.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
public class XMLWriterDOM {
public static void main(String[] args) {
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder;
try {
dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.newDocument();
//add elements to Document
Element rootElement =
doc.createElementNS("http://www.journaldev.com/employee", "Employees");
//append root element to document
doc.appendChild(rootElement);
//append first child element to root element
rootElement.appendChild(getEmployee(doc, "1", "Pankaj", "29", "Java Developer", "Male"));
//append second child
rootElement.appendChild(getEmployee(doc, "2", "Lisa", "35", "Manager", "Female"));
//for output to file, console
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
//for pretty print
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
DOMSource source = new DOMSource(doc);
//write to console or file
StreamResult console = new StreamResult(System.out);
StreamResult file = new StreamResult(new File("/Users/pankaj/emps.xml"));
//write data
transformer.transform(source, console);
transformer.transform(source, file);
System.out.println("DONE");
} catch (Exception e) {
e.printStackTrace();
}
}
private static Node getEmployee(Document doc, String id, String name, String age, String role,
String gender) {
Element employee = doc.createElement("Employee");
//set id attribute
employee.setAttribute("id", id);
//create name element
employee.appendChild(getEmployeeElements(doc, employee, "name", name));
//create age element
employee.appendChild(getEmployeeElements(doc, employee, "age", age));
//create role element
employee.appendChild(getEmployeeElements(doc, employee, "role", role));
//create gender element
employee.appendChild(getEmployeeElements(doc, employee, "gender", gender));
return employee;
}
//utility method to create text node
private static Node getEmployeeElements(Document doc, Element element, String name, String value) {
Element node = doc.createElement(name);
node.appendChild(doc.createTextNode(value));
return node;
}
}需要注意的是代码中创建了两个StreamResult对象，一个是出于调试的目的將XML文件内容输出到控制台中，另一个將XML内容写到文件中。
程序输出的XML内容：
<?xml version="1.0" encoding="UTF-8" standalone="no"?> <Employees xmlns=" <Employee id="1"><name>Pankaj</name><age>29</age><role>Java Developer</role><gender>Male</gender></Employee> <Employee id="2"><name>Lisa</name><age>35</age><role>Manager</role><gender>Female</gender></Employee></Employees>
该XML内容没有格式化，如果你需要对XML内容做适当的格式化，参考这篇文章Java中格式化XML
在前面的教程中，我们学习了使用DOM解析方式读取和修改XML文件内容，今天我们来学习如何使用DOM解析机制生成XML文件。
下面是我们对要生成的XML文件的具体要求：
1.根节点元素为”Employees”,命名空间为”//m.sbmmt.com/“,根节点下包含一系列的Employee元素。
2.员工的信息通过Employee节点表示，生成的XML文件有两条员工的信息。
3.每个员工有个”id”属性。
4.Employee 元素有四个子元素- “name”, “age”, “role”, “gender”。
下面是程序代码：
package com.journaldev.xml;
import java.io.File;
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.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
public class XMLWriterDOM {
public static void main(String[] args) {
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder;
try {
dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.newDocument();
//add elements to Document
Element rootElement =
doc.createElementNS("http://www.journaldev.com/employee", "Employees");
//append root element to document
doc.appendChild(rootElement);
//append first child element to root element
rootElement.appendChild(getEmployee(doc, "1", "Pankaj", "29", "Java Developer", "Male"));
//append second child
rootElement.appendChild(getEmployee(doc, "2", "Lisa", "35", "Manager", "Female"));
//for output to file, console
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
//for pretty print
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
DOMSource source = new DOMSource(doc);
//write to console or file
StreamResult console = new StreamResult(System.out);
StreamResult file = new StreamResult(new File("/Users/pankaj/emps.xml"));
//write data
transformer.transform(source, console);
transformer.transform(source, file);
System.out.println("DONE");
} catch (Exception e) {
e.printStackTrace();
}
}
private static Node getEmployee(Document doc, String id, String name, String age, String role,
String gender) {
Element employee = doc.createElement("Employee");
//set id attribute
employee.setAttribute("id", id);
//create name element
employee.appendChild(getEmployeeElements(doc, employee, "name", name));
//create age element
employee.appendChild(getEmployeeElements(doc, employee, "age", age));
//create role element
employee.appendChild(getEmployeeElements(doc, employee, "role", role));
//create gender element
employee.appendChild(getEmployeeElements(doc, employee, "gender", gender));
return employee;
}
//utility method to create text node
private static Node getEmployeeElements(Document doc, Element element, String name, String value) {
Element node = doc.createElement(name);
node.appendChild(doc.createTextNode(value));
return node;
}
}需要注意的是代码中创建了两个StreamResult对象，一个是出于调试的目的將XML文件内容输出到控制台中，另一个將XML内容写到文件中。
程序输出的XML内容：
<?xml version="1.0" encoding="UTF-8" standalone="no"?> <Employees xmlns=" <Employee id="1"><name>Pankaj</name><age>29</age><role>Java Developer</role><gender>Male</gender></Employee> <Employee id="2"><name>Lisa</name><age>35</age><role>Manager</role><gender>Female</gender></Employee></Employees>
以上就是Java&Xml教程（四）使用DOM方式生成XML文件的内容，更多相关内容请关注PHP中文网（m.sbmmt.com）！
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