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;
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。
/** Dom方式，创建 XML */
public String domCreateXML() {
String xmlWriter = null;
Person []persons = new Person[3]; // 创建节点Person对象
persons[0] = new Person(1, "sunboy_2050", "//www.zyiz.net/");
persons[1] = new Person(2, "baidu", "http://wwwbaiducom");
persons[2] = new Person(3, "google", "http://wwwgooglecom");
try {
DocumentBuilderFactory factory = DocumentBuilderFactorynewInstance();
DocumentBuilder builder = factorynewDocumentBuilder();
Document doc = buildernewDocument();
Element eleRoot = doccreateElement("root");
eleRootsetAttribute("author", "homer");
eleRootsetAttribute("date", "2012-04-26");
docappendChild(eleRoot);
int personsLen = personslength;
for(int i=0; i<personsLen; i++) {
Element elePerson = doccreateElement("person");
eleRootappendChild(elePerson);
Element eleId = doccreateElement("id");
Node nodeId = doccreateTextNode(persons[i]getId() + "");
eleIdappendChild(nodeId);
elePersonappendChild(eleId);
Element eleName = doccreateElement("name");
Node nodeName = doccreateTextNode(persons[i]getName());
eleNameappendChild(nodeName);
elePersonappendChild(eleName);
Element eleBlog = doccreateElement("blog");
Node nodeBlog = doccreateTextNode(persons[i]getBlog());
eleBlogappendChild(nodeBlog);
elePersonappendChild(eleBlog);
}
Properties properties = new Properties();
propertiessetProperty(OutputKeysINDENT, "yes");
propertiessetProperty(OutputKeysMEDIA_TYPE, "xml");
propertiessetProperty(OutputKeysVERSION, "0");
propertiessetProperty(OutputKeysENCODING, "utf-8");
propertiessetProperty(OutputKeysMETHOD, "xml");
propertiessetProperty(OutputKeysOMIT_XML_DECLARATION, "yes");
TransformerFactory transformerFactory = TransformerFactorynewInstance();
Transformer transformer = transformerFactorynewTransformer();
transformersetOutputProperties(properties);
DOMSource domSource = new DOMSource(docgetDocumentElement());
OutputStream output = new ByteArrayOutputStream();
StreamResult result = new StreamResult(output);
transformertransform(domSource, result);
xmlWriter = outputtoString();
} catch (ParserConfigurationException e) { // factorynewDocumentBuilder
eprintStackTrace();
} catch (DOMException e) { // doccreateElement
eprintStackTrace();
} catch (TransformerFactoryConfigurationError e) { // TransformerFactorynewInstance
eprintStackTrace();
} catch (TransformerConfigurationException e) { // transformerFactorynewTransformer
eprintStackTrace();
} catch (TransformerException e) { // transformertransform
eprintStackTrace();
} catch (Exception e) {
eprintStackTrace();
}
savedXML(fileName, xmlWritertoString());
return xmlWritertoString();
}
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。
/** Dom方式，解析 XML */
public String domResolveXML() {
StringWriter xmlWriter = new StringWriter();
InputStream is= readXML(fileName);
try {
DocumentBuilderFactory factory = DocumentBuilderFactorynewInstance();
DocumentBuilder builder = factorynewDocumentBuilder();
Document doc = builderparse(is);
docgetDocumentElement()normalize();
NodeList nlRoot = docgetElementsByTagName("root");
Element eleRoot = (Element)nlRootitem(0);
String attrAuthor = eleRootgetAttribute("author");
String attrDate = eleRootgetAttribute("date");
xmlWriterappend("root")append("\t\t");
xmlWriterappend(attrAuthor)append("\t");
xmlWriterappend(attrDate)append("\n");
NodeList nlPerson = eleRootgetElementsByTagName("person");
int personsLen = nlPersongetLength();
Person []persons = new Person[personsLen];
for(int i=0; i<personsLen; i++) {
Element elePerson = (Element) nlPersonitem(i); // person节点
Person person = new Person(); // 创建Person对象
NodeList nlId = elePersongetElementsByTagName("id");
Element eleId = (Element)nlIditem(0);
String id = eleIdgetChildNodes()item(0)getNodeValue();
personsetId(IntegerparseInt(id));
NodeList nlName = elePersongetElementsByTagName("name");
Element eleName = (Element)nlNameitem(0);
String name = eleNamegetChildNodes()item(0)getNodeValue();
personsetName(name);
NodeList nlBlog = elePersongetElementsByTagName("blog");
Element eleBlog = (Element)nlBlogitem(0);
String blog = eleBloggetChildNodes()item(0)getNodeValue();
personsetBlog(blog);
xmlWriterappend(persontoString())append("\n");
persons[i] = person;
}
} catch (ParserConfigurationException e) { // factorynewDocumentBuilder
eprintStackTrace();
} catch (SAXException e) { // builderparse
eprintStackTrace();
} catch (IOException e) { // builderparse
eprintStackTrace();
} catch (Exception e) {
eprintStackTrace();
}
return xmlWritertoString();
}
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
public class Person {
private int id;
private String name;
private String blog;
public Person() {
thisid = -1;
thisname = "";
thisblog = "";
}
public Person(int id, String name, String blog) {
thisid = id;
thisname = name;
thisblog = blog;
}
public Person(Person person) {
thisid = personid;
thisname = personname;
thisblog = personblog;
}
public Person getPerson(){
return this;
}
public void setId(int id) {
thisid = id;
}
public int getId(){
return thisid;
}
public void setName(String name) {
thisname = name;
}
public String getName() {
return thisname;
}
public void setBlog(String blog) {
thisblog = blog;
}
public String getBlog() {
return thisblog;
}
public String toString() {
return "Person \nid = " + id + "\nname = " + name + "\nblog = " + blog + "\n";
}
}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持找一找教程网。
