1 <?xml version="1.0" encoding="utf-8"?> 2 <root> 3 <class name="class1"> 4 <student> 5 <name>张三</name> 6 <age>20</age> 7 <sex>男</sex> 8 </student> 9 <student> 10 <name>Andy</name> 11 <age>22</age> 12 <sex>female</sex> 13 </student> 14 </class> 15 <class name="class2"> 16 <student> 17 <name>李四</name> 18 <age>15</age> 19 <sex>男</sex> 20 </student> 21 <student> 22 <name>bigbang</name> 23 <age>21</age> 24 <sex>女</sex> 25 </student> 26 </class> 27 </root>
1. DOM解析是一种消耗内存的解析方法，它先将整个xml文档装入内存，然后顺序读取，解析有些复杂。
1 import java.io.IOException;
2 import java.util.ArrayList;
3 import java.util.List;
4
5 import javax.xml.parsers.DocumentBuilder;
6 import javax.xml.parsers.DocumentBuilderFactory;
7 import javax.xml.parsers.ParserConfigurationException;
8
9 import org.w3c.dom.Document;
10 import org.w3c.dom.Element;
11 import org.w3c.dom.Node;
12 import org.w3c.dom.NodeList;
13 import org.xml.sax.SAXException;
14
15 import com.entity.Student;
16
17 public class DOMParse {
18
19 private Student student;
20 private List<Student> students;
21
22 public void pasre() {
23 students = new ArrayList<Student>();
24 try {
25 DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
26 DocumentBuilder builder = dbf.newDocumentBuilder();
27 // 在此没有使用InputStream作为参数，直接引用文件路径。
28 Document doc = builder.parse("src/com/parseDom/test.xml");
29 // 获取整个document元素
30 Element element = doc.getDocumentElement();
31 // 获取所有<class>子节点
32 NodeList list = element.getElementsByTagName("class"); // <class>
33 // 遍历class子节点
34 for (int i = 0; i < list.getLength(); i++) {
35 Element el = (Element) list.item(i);
36 // 获取<student>节点
37 NodeList stus = el.getElementsByTagName("student"); // <student>
38 // 遍历student子节点
39 for (int j = 0; j < stus.getLength(); j++) {
40 /**
41 * 获取student下所有子节点 此处有7个节点，分别是#text<name> #text<sex>
42 * #text<age> #text
43 * 对应的xml实际是<student>、<name>、#name、<sex>、#sex
44 * 、<age>、#age这七个子节点
45 * **/
46 NodeList lis = stus.item(j).getChildNodes();
47 // 每个student节点输出就是一个Student对象
48 student = new Student();
49 for (int k = 0; k < lis.getLength(); k++) {
50 // 当元素为节点元素时（非textValue），对比后取值
51 if (lis.item(k).getNodeType() == Node.ELEMENT_NODE) {
52 if ("name".equals(lis.item(k).getNodeName())) { // <name>
53 student.setName(lis.item(k).getFirstChild().getNodeValue());
54 }
55 if ("sex".equals(lis.item(k).getNodeName())) { // <sex>
56 student.setSex(lis.item(k).getFirstChild().getNodeValue());
57 }
58 if ("age".equals(lis.item(k).getNodeName())) { // <age>
59 student.setAge(Integer.parseInt(lis.item(k).getFirstChild().getNodeValue()));
60 }
61 }
62 }
63 students.add(student);
64 }
65 }
66
67 } catch (ParserConfigurationException e) {
68 e.printStackTrace();
69 } catch (SAXException e) {
70 e.printStackTrace();
71 } catch (IOException e) {
72 e.printStackTrace();
73 } finally {
74 for (Student stus : students) {
75 System.out.println(stus.getName() + "--" + stus.getSex() + "--" + stus.getAge());
76 }
77 }
78 }
79
80 public static void main(String[] args) {
81 DOMParse domParse = new DOMParse();
82 domParse.pasre();
83 }
84 }
2.SAX解析方法如下。
1 import java.io.IOException;
2 import java.util.ArrayList;
3 import java.util.List;
4
5 import javax.xml.parsers.ParserConfigurationException;
6 import javax.xml.parsers.SAXParser;
7 import javax.xml.parsers.SAXParserFactory;
8
9 import org.xml.sax.Attributes;
10 import org.xml.sax.SAXException;
11 import org.xml.sax.helpers.DefaultHandler;
12
13 import com.entity.Student;
14
15 public class SAXParse extends DefaultHandler{
16
17
18 private Student student;
19 private static List<Student> stus;
20 private String preTag=null;
21
22 //①程序启动执行
23 @Override
24 public void startDocument() throws SAXException {
25 stus = new ArrayList<Student>();
26 }
27
28 //② 开始遍历元素时
29 @Override
30 public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
31 if("student".equals(qName)){
32 student = new Student();
33 // student.setName(attributes.getValue(0));
34 }
35 preTag = qName;
36 }
37
38 //④元素遍历结束
39 @Override
40 public void endElement(String uri, String localName, String qName) throws SAXException {
41 if("student".equals(qName)){
42 stus.add(student);
43 student = null;
44 }
45 preTag=null;
46 }
47
48 //③ 遍历取值过程
49 @Override
50 public void characters(char[] ch, int start, int length) throws SAXException {
51 if(preTag!=null){
52 String content = new String(ch,start,length);
53 if("name".equals(preTag)){
54 student.setName(content);
55 }
56 if("age".equals(preTag)){
57 student.setAge(Integer.parseInt(content));
58 }
59 if("sex".equals(preTag)){
60 student.setSex(content);
61 }
62 }
63 }
64
65 public void fun(){
66 try {
67 SAXParserFactory factory =SAXParserFactory.newInstance();
68 SAXParser parser = factory.newSAXParser();
69 SAXParse handler = new SAXParse();
70 parser.parse("src/com/parseDom/test.xml", handler);
71 } catch (ParserConfigurationException e) {
72 e.printStackTrace();
73 } catch (SAXException e) {
74 e.printStackTrace();
75 } catch (IOException e) {
76 e.printStackTrace();
77 }
78 }
79
80 public static List<Student> getStus(){
81 return stus;
82 }
83
84 public static void main(String[] args) {
85 new SAXParse().fun();
86 for (Student stu : getStus()) {
87 System.out.println(stu.getName()+"--"+stu.getAge()+"--"+stu.getSex());
88 }
89 }
90 }
3.DOM4J的解析方法如下，需要注意的是它的Document类和Element类是DOM4J的jar包提供的，不要引用错了。
1 import java.util.ArrayList;
2 import java.util.Iterator;
3 import java.util.List;
4
5 import org.dom4j.Document;
6 import org.dom4j.DocumentException;
7 import org.dom4j.Element;
8 import org.dom4j.io.SAXReader;
9
10 import com.entity.Student;
11
12 public class DOM4J {
13
14 private Student student;
15 private List<Student> stus;
16
17 @SuppressWarnings("unchecked")
18 public void parse(){
19 stus = new ArrayList<Student>();
20 try {
21 SAXReader reader = new SAXReader();
22
23 //此处Document类和Element类均为DOM4j的jar包中的类
24 Document doc = reader.read("src/com/parseDom/test.xml");
25 //获取根元素
26 Element root = doc.getRootElement();
27 //获取节点元素为"class"的迭代
28 Iterator<Element> classss = root.elementIterator("class");
29 while(classss.hasNext()){
30 Element classs =classss.next();
31 //获取节点元素为"student"的迭代
32 Iterator<Element> students = classs.elementIterator("student");
33 while (students.hasNext()) {
34 //每一个student节点元素都包括一个student对象
35 student = new Student();
36 Element els = students.next();
37 //根据节点元素取值
38 student.setName(els.elementText("name"));
39 student.setAge(Integer.parseInt(els.elementText("age")));
40 student.setSex(els.elementText("sex"));
41 stus.add(student);
42 }
43 }
44 } catch (DocumentException e) {
45 e.printStackTrace();
46 } finally{
47 for (Student stu : stus) {
48 System.out.println(stu.getName()+"++"+stu.getSex()+"++"+stu.getAge());
49 }
50 }
51 }
52
53
54 public static void main(String[] args) {
55 new DOM4J().parse();
56 }
57 }
最后的输出结果是：
1 张三++男++20 2 Andy++female++22 3 李四++男++15 4 bigbang++女++21
时间： 2024-11-03 13:43:25