DOM解析XML-蒲公英云

下面是DOM解析XML的示例，包括三个文件employee.xml、Employee.java、DomEmployee.java

1.被解析的employee.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE employees [
    <!ELEMENT employees (employee*)>
    <!ELEMENT employee (name,age,gender,email,salary)>
    <!ATTLIST employee id  CDATA #IMPLIED> 
    <!ATTLIST employee depName CDATA #IMPLIED> 
    <!ELEMENT name (#PCDATA)>
    <!ELEMENT age (#PCDATA)>
    <!ELEMENT gender (#PCDATA)>
    <!ELEMENT email (#PCDATA)>
    <!ELEMENT salary (#PCDATA)>
]>
<employees>
    <employee id="1" depName="教学部">
        <name>tom</name>
        <age>20</age>
        <gender>male</gender>
        <email>tom@163.com</email>
        <salary>10k</salary>
    </employee>
    <employee id="2" depName="教学部">
        <name>jack</name>
        <age>30</age>
        <gender>female</gender>
        <email>jack@163.com</email>
        <salary>8k</salary>
    </employee>
    <employee id="3" depName="市场部">
        <name>rose</name>
        <age>25</age>
        <gender>female</gender>
        <email>rose@163.com</email>
        <salary>5k</salary>
    </employee>
    <employee id="4" depName="教学管理部">
        <name>mark</name>
        <age>30</age>
        <gender>male</gender>
        <email>mark@163.com</email>
        <salary>5k</salary>
    </employee>
</employees>

2.Employee.java文件

package exercise;
public class Employee {
    private int id;
    private String depName;
    private String name;
    private int age;
    private String gender;
    private String email;
    private String salary;
    public Employee() {
    }
    public Employee(int id, String depName, String name, int age, String gender, String email, String salary) {
        super();
        this.id = id;
        this.depName = depName;
        this.name = name;
        this.age = age;
        this.gender = gender;
        this.email = email;
        this.salary = salary;
    }
    @Override
    public String toString() {
        return "Employee [id=" + id + ", depName=" + depName + ", name=" + name + ", age=" + age + ", gender=" + gender
                + ", email=" + email + ", salary=" + salary + "]";
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getDepName() {
        return depName;
    }
    public void setDepName(String depName) {
        this.depName = depName;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getGender() {
        return gender;
    }
    public void setGender(String gender) {
        this.gender = gender;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public String getSalary() {
        return salary;
    }
    public void setSalary(String salary) {
        this.salary = salary;
    }
}

3.DomEmployee.java实现解析

package exercise;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/**
 * 我们利用Dom解析读取employee.xml文件中的员工信息，将其存放到容器中
 * 同时我们加入封装的思想
 * @author www11
 *
 */
public class DomEmployee {
    private  List<Employee> list;  //创建一个容器用于保存Employee对象
    private  Employee employee;    //接受每一个employee
    public DomEmployee() {        //构造器
        list = new ArrayList<Employee>();
    }    
    public List<Employee> getList() { //提供getList()方法，从外部获取
        return list;
    }
    //获取文档树类型对象的函数，大家不要被try..catch语句给迷惑，代码很简单
    private Document getDocument(File file) {
        //1.创建Dom解析工厂
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        Document document = null;
        //2.用工厂生成一个Dom构建器
        try {
            DocumentBuilder builder = factory.newDocumentBuilder();
            try {
                //3.用Dom构建器去调用其中的解析方法,方法返回一个文档树类型的对象，我们只要对这个文档树对象操作就可以得到想要的结果了
                document = builder.parse(file);
            }catch (Exception e) {
                e.printStackTrace();
            }    
        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        }
        return document;
    }
    //将获取到的文档解析出来的结果添加到list中
    private void parser(Document document) {
        //直接通过标签名获得节点集合
        NodeList nodeList = document.getElementsByTagName("employee");
        for(int i = 0; i < nodeList.getLength();i++) {
            //将每一个节点转换为元素类型
            Element e = (Element)nodeList.item(i);
            employee = new Employee();
            String id = e.getAttribute("id");       //通过属性名直接获取属性值
            String depName = e.getAttribute("depName");
            employee.setId(Integer.parseInt(id));   //将获取到的值赋给employee
            employee.setDepName(depName);
            NodeList nodeList2 = e.getChildNodes();  //获取到子节点集合，其中包括name，age，gender，email，salary
            for(int j = 0;j<nodeList2.getLength();j++) {
                if(nodeList2.item(j).getNodeType() == Node.ELEMENT_NODE) {  //这个判断用于去掉空文本
                    String name = nodeList2.item(j).getNodeName();   //获取到当前节点的名字
                    String value = nodeList2.item(j).getTextContent();  //获取到当前节点的文本内容
                    //将对应的值赋给相应的变量
                    if(name.equals("name")) { 
                        employee.setName(value);
                    }else if(name.equals("age")) {
                        employee.setAge(Integer.parseInt(value));
                    }else if(name.equals("gender")) {
                        employee.setGender(value);
                    }else if(name.equals("email")) {
                        employee.setEmail(value);
                    }else if(name.equals("salary")) {
                        employee.setSalary(value);
                    }
                }
            }
            list.add(employee);    //将本次读取到的employee加入到容器中
        }
    }
    //主函数测试
    public static void main(String[] args) throws Exception {    
        DomEmployee dom = new DomEmployee();
        File file = new File("src/exercise/employee.xml");
        Document document = dom.getDocument(file);
        dom.parser(document);
        List<Employee> list = dom.getList();
        for(Employee e : list) {
            System.out.println(e);
        }
    }
}