一、基本介绍
对XML解析有SAX和DOM等多种方式,Android中极力推荐xmlpull方式解析xml。xmlpull不仅可用在Android上同样也适用于javase,但在javase环境中需自己获取xmlpull所依赖的类库,kxml2-2.3.0.jar,xmlpull_1_1_3_4c.jar。
jar包下载网址
http://www.xmlpull.org/
http://kxml.sourceforge.net/
二、例子
读取到xml的声明返回数字0 START_DOCUMENT;
读取到xml的结束返回数字1 END_DOCUMENT ;
读取到xml的开始标签返回数字2 START_TAG
读取到xml的结束标签返回数字3 END_TAG
读取到xml的文本返回数字4 TEXT
<?xml version="1.0" encoding="UTF-8"?> <people> <person id="001"> <name>XY1</name> <age>22</age> </person> <person id="002"> <name>XY2</name> <age>22</age> </person> </people>
package cn.xy.service; import java.io.InputStream; import java.io.OutputStream; import java.util.ArrayList; import java.util.List; import org.xmlpull.v1.XmlPullParser; import org.xmlpull.v1.XmlSerializer; import android.util.Xml; import cn.xy.model.Person; /** * 利用pull解析器解析XML * * @author XY * */ public class PersonService { /** * 从XML文件中读取数据 * * @param xml XML文件输入流 */ public List<Person> getPeople(InputStream xml) throws Exception { List<Person> lst = null; Person person = null; // 利用ANDROID提供的API快速获得pull解析器 XmlPullParser pullParser = Xml.newPullParser(); // 设置需要解析的XML数据 pullParser.setInput(xml, "UTF-8"); // 取得事件 int event = pullParser.getEventType(); // 若为解析到末尾 while (event != XmlPullParser.END_DOCUMENT) // 文档结束 { String nodeName = pullParser.getName(); switch (event) { case XmlPullParser.START_DOCUMENT: // 文档开始 lst = new ArrayList<Person>(); break; case XmlPullParser.START_TAG: // 标签开始 if ("person".equals(nodeName)) { String id = pullParser.getAttributeValue(0); person = new Person(); person.setId(id); } if ("name".equals(nodeName)) { String name = pullParser.nextText(); person.setName(name); } if ("age".equals(nodeName)) { int age = Integer.valueOf(pullParser.nextText()); person.setAge(age); } break; case XmlPullParser.END_TAG: // 标签结束 if ("person".equals(nodeName)) { lst.add(person); person = null; } break; } event = pullParser.next(); // 下一个标签 } return lst; } /** * 向XML写入数据 * * @param os * @param person * @throws Exception */ public void saveDataToXML(OutputStream os, List<Person> lst) throws Exception { XmlSerializer xs = Xml.newSerializer(); xs.setOutput(os, "UTF-8"); xs.startDocument("UTF-8", true); xs.startTag(null, "people"); for (Person p : lst) { xs.startTag(null, "person"); xs.attribute(null, "person", p.getId()); xs.startTag(null, "name"); xs.text(p.getName()); xs.endTag(null, "name"); xs.startTag(null, "age"); xs.text(p.getAge().toString()); xs.endTag(null, "age"); xs.endTag(null, "person"); } xs.endTag(null, "people"); xs.endDocument(); os.flush(); os.close(); } }
public class TestClass extends AndroidTestCase { public void testPeople() throws Exception { PersonService ps = new PersonService(); InputStream xml = this.getClass().getClassLoader().getResourceAsStream("person.xml"); List<Person> lst = ps.getPeople(xml); Assert.assertEquals("XY1", lst.get(0).getName()); } public void testSave() throws Exception { PersonService ps = new PersonService(); List<Person> lst = new ArrayList<Person>(); lst.add(new Person("0001", "XY0001", 20)); lst.add(new Person("0002", "XY0002", 20)); File xmlFile = new File(this.getContext().getFilesDir(), "xy.xml"); // data/data/package name/files OutputStream os = new FileOutputStream(xmlFile); ps.saveDataToXML(os, lst); } }