Android 创建与解析XML（二）—— Dom方式

1. Dom概述

Dom方式创建XML，应用了标准xml构造器 javax.xml.parsers.DocumentBuilder 来创建 XML 文档，需要导入以下内容

javax.xml.parsers

javax.xml.parsers.DocumentBuilder 

javax.xml.parsers.DocumentBuilderFactory 

javax.xml.parsers.ParserConfigurationException;

javax.xml.transform

javax.xml.transform.TransformerFactory 

javax.xml.transform.Transformer 

javax.xml.transform.dom.DOMSource 

javax.xml.transform.stream.StreamResult 

javax.xml.transform.OutputKeys;

javax.xml.transform.TransformerFactoryConfigurationError;

javax.xml.transform.TransformerConfigurationException;

javax.xml.transform.TransformerException;

org.w3c.dom 

org.w3c.dom.Document;

org.w3c.dom.Element;

org.w3c.dom.Node;

org.w3c.dom.DOMException;

org.w3c.dom.NodeList;

org.xml.sax.SAXException;

sdk源码查看路径（​​google code​​）

创建和解析xml的效果图：

2、Dom 创建 XML

Dom，借助 javax.xml.parsers.DocumentBuilder，可以创建 org.w3c.dom.Document 对象。

使用来自 DocumentBuilderFactory 的 DocumentBuilder 对象在 Android 设备上创建与解析 XML 文档。您将使用 XML pull 解析器的扩展来解析 XML 文档。

Code

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1. /** Dom方式，创建 XML  */
2. public String domCreateXML() {
3. null;
4. 
5. new Person[3];       // 创建节点Person对象
6. 0] = new Person(1, "sunboy_2050", );
7. 1] = new Person(2, "baidu", "http://www.baidu.com");
8. 2] = new Person(3, "google", "http://www.google.com");
9. 
10. try {
11. DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
12. DocumentBuilder builder = factory.newDocumentBuilder();
13. Document doc = builder.newDocument();
14. 
15. "root");
16. "author", "homer");
17. "date", "2012-04-26");
18. doc.appendChild(eleRoot);
19. 
20. int personsLen = persons.length;
21. for(int i=0; i<personsLen; i++) {
22. "person");
23. eleRoot.appendChild(elePerson);
24. 
25. "id");
26. "");
27. eleId.appendChild(nodeId);
28. elePerson.appendChild(eleId);
29. 
30. "name");
31. Node nodeName = doc.createTextNode(persons[i].getName());
32. eleName.appendChild(nodeName);
33. elePerson.appendChild(eleName);
34. 
35. "blog");
36. Node nodeBlog = doc.createTextNode(persons[i].getBlog());
37. eleBlog.appendChild(nodeBlog);
38. elePerson.appendChild(eleBlog);
39. }
40. 
41. 
42. new Properties();
43. "yes");
44. "xml");
45. "1.0");
46. "utf-8");
47. "xml");
48. "yes");
49. 
50. TransformerFactory transformerFactory = TransformerFactory.newInstance();
51. Transformer transformer = transformerFactory.newTransformer();
52. transformer.setOutputProperties(properties);
53. 
54. new DOMSource(doc.getDocumentElement());
55. new ByteArrayOutputStream();
56. new StreamResult(output);
57. transformer.transform(domSource, result);
58. 
59. xmlWriter = output.toString();
60. 
61. catch (ParserConfigurationException e) {      // factory.newDocumentBuilder
62. e.printStackTrace();
63. catch (DOMException e) {                      // doc.createElement
64. e.printStackTrace();
65. catch (TransformerFactoryConfigurationError e) {      // TransformerFactory.newInstance
66. e.printStackTrace();
67. catch (TransformerConfigurationException e) {     // transformerFactory.newTransformer
68. e.printStackTrace();
69. catch (TransformerException e) {              // transformer.transform
70. e.printStackTrace();
71. catch (Exception e) {
72. e.printStackTrace();
73. }
74. 
75. savedXML(fileName, xmlWriter.toString());
76. 
77. return xmlWriter.toString();
78. }

运行结果：

3、Dom 解析 XML

Dom方式，解析XML是创建XML的逆过程，主要用到了builder.parse(is)进行解析，然后通过Tag、NodeList、Element、childNotes等得到Element和Node属性或值。

Code

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1. /** Dom方式，解析 XML  */
2. public String domResolveXML() {
3. new StringWriter();
4. 
5. InputStream is= readXML(fileName);
6. try {
7. DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
8. DocumentBuilder builder = factory.newDocumentBuilder();
9. Document doc = builder.parse(is);
10. 
11. doc.getDocumentElement().normalize();
12. "root");
13. 0);
14. "author");
15. "date");
16. "root").append("\t\t");
17. "\t");
18. "\n");
19. 
20. "person");
21. int personsLen = nlPerson.getLength();
22. new Person[personsLen];
23. for(int i=0; i<personsLen; i++) {
24. // person节点
25. new Person();                       // 创建Person对象
26. 
27. "id");
28. 0);
29. 0).getNodeValue();
30. person.setId(Integer.parseInt(id));
31. 
32. "name");
33. 0);
34. 0).getNodeValue();
35. person.setName(name);
36. 
37. "blog");
38. 0);
39. 0).getNodeValue();
40. person.setBlog(blog);
41. 
42. "\n");
43. persons[i] = person;
44. }
45. 
46. catch (ParserConfigurationException e) {      // factory.newDocumentBuilder
47. e.printStackTrace();
48. catch (SAXException e) {      // builder.parse
49. e.printStackTrace();
50. catch (IOException e) {       // builder.parse
51. e.printStackTrace();
52. catch (Exception e) {
53. e.printStackTrace();
54. }
55. 
56. return xmlWriter.toString();
57. }

运行结果：

4、Person类

Person类，是创建xml的单位实例，基于Java面向对象定义的一个类

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1. public class Person {
2. private int id;
3. private String name;
4. private String blog;
5. 
6. public Person() {
7. this.id = -1;
8. this.name = "";
9. this.blog = "";
10. }
11. 
12. public Person(int id, String name, String blog) {
13. this.id = id;
14. this.name = name;
15. this.blog = blog;
16. }
17. 
18. public Person(Person person) {
19. this.id = person.id;
20. this.name = person.name;
21. this.blog = person.blog;
22. }
23. 
24. public Person getPerson(){
25. return this;
26. }
27. 
28. public void setId(int id) {
29. this.id = id;
30. }
31. 
32. public int getId(){
33. return this.id;
34. }
35. 
36. public void setName(String name) {
37. this.name = name;
38. }
39. 
40. public String getName() {
41. return this.name;
42. }
43. 
44. public void setBlog(String blog) {
45. this.blog = blog;
46. }
47. 
48. public String getBlog() {
49. return this.blog;
50. }
51. 
52. public String toString() {
53. return "Person \nid = " + id + "\nname = " + name + "\nblog = " + blog + "\n";
54. }
55. }