Android XML数据的三种解析方式

<students>
 <student>
  <name sex="man">小明</name>
  <nickName>明明</nickName>
 </student>
 <student>
  <name sex="woman">小红</name>
  <nickName>红红</nickName>
 </student>
 <student>
  <name sex="man">小亮</name>
  <nickName>亮亮</nickName>
 </student>
</students>

public class Student {
 private String name;
 private String sex;
 private String nickName;

 public String getName() {
  return name;
 }

 public void setName(String name) {
  this.name = name;
 }

 public String getSex() {
  return sex;
 }

 public void setSex(String sex) {
  this.sex = sex;
 }

 public String getNickName() {
  return nickName;
 }

 public void setNickName(String nickName) {
  this.nickName = nickName;
 }

 @Override
 public String toString() {
  return "Student{" +
    "name='" + name + '\'' +
    ", sex='" + sex + '\'' +
    ", nickName='" + nickName + '\'' +
    '}';
 }
}

public List<Student> dom2xml(InputStream is) throws Exception {
 //一系列的初始化
 List<Student> list = new ArrayList<>();
 DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
 DocumentBuilder builder = factory.newDocumentBuilder();
 //获得Document对象
 Document document = builder.parse(is);
 //获得student的List
 NodeList studentList = document.getElementsByTagName("student");
 //遍历student标签
 for (int i = 0; i < studentList.getLength(); i++) {
  //获得student标签
  Node node_student = studentList.item(i);
  //获得student标签里面的标签
  NodeList childNodes = node_student.getChildNodes();
  //新建student对象
  Student student = new Student();
  //遍历student标签里面的标签
  for (int j = 0; j < childNodes.getLength(); j++) {
   //获得name和nickName标签
   Node childNode = childNodes.item(j);
   //判断是name还是nickName
   if ("name".equals(childNode.getNodeName())) {
    String name = childNode.getTextContent();
    student.setName(name);
    //获取name的属性
    NamedNodeMap nnm = childNode.getAttributes();
    //获取sex属性，由于只有一个属性，所以取0
    Node n = nnm.item(0);
    student.setSex(n.getTextContent());
   } else if ("nickName".equals(childNode.getNodeName())) {
    String nickName = childNode.getTextContent();
    student.setNickName(nickName);
   }
  }
  //加到List中
  list.add(student);
 }
 return list;
}

public List<Student> sax2xml(InputStream is) throws Exception {
 SAXParserFactory spf = SAXParserFactory.newInstance();
 //初始化Sax解析器
 SAXParser sp = spf.newSAXParser();
 //新建解析处理器
 MyHandler handler = new MyHandler();
 //将解析交给处理器
 sp.parse(is, handler);
 //返回List
 return handler.getList();
}

public class MyHandler extends DefaultHandler {

 private List<Student> list;
 private Student student;
 //用于存储读取的临时变量
 private String tempString;

 /**
  * 解析到文档开始调用，一般做初始化操作
  *
  * @throws SAXException
  */
 @Override
 public void startDocument() throws SAXException {
  list = new ArrayList<>();
  super.startDocument();
 }

 /**
  * 解析到文档末尾调用，一般做回收操作
  *
  * @throws SAXException
  */
 @Override
 public void endDocument() throws SAXException {
  super.endDocument();
 }

 /**
  * 每读到一个元素就调用该方法
  *
  * @param uri
  * @param localName
  * @param qName
  * @param attributes
  * @throws SAXException
  */
 @Override
 public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
  if ("student".equals(qName)) {
   //读到student标签
   student = new Student();
  } else if ("name".equals(qName)) {
   //获取name里面的属性
   String sex = attributes.getValue("sex");
   student.setSex(sex);
  }
  super.startElement(uri, localName, qName, attributes);
 }

 /**
  * 读到元素的结尾调用
  *
  * @param uri
  * @param localName
  * @param qName
  * @throws SAXException
  */
 @Override
 public void endElement(String uri, String localName, String qName) throws SAXException {
  if ("student".equals(qName)) {
   list.add(student);
  }
  if ("name".equals(qName)) {
   student.setName(tempString);
  } else if ("nickName".equals(qName)) {
   student.setNickName(qName);
  }
  super.endElement(uri, localName, qName);
 }

 /**
  * 读到属性内容调用
  *
  * @param ch
  * @param start
  * @param length
  * @throws SAXException
  */
 @Override
 public void characters(char[] ch, int start, int length) throws SAXException {
  tempString = new String(ch, start, length);
  super.characters(ch, start, length);
 }

 /**
  * 获取该List
  *
  * @return
  */
 public List<Student> getList() {
  return list;
 }
}

public List<Student> pull2xml(InputStream is) throws Exception {
 List<Student> list = null;
 Student student = null;
 //创建xmlPull解析器
 XmlPullParser parser = Xml.newPullParser();
 ///初始化xmlPull解析器
 parser.setInput(is, "utf-8");
 //读取文件的类型
 int type = parser.getEventType();
 //无限判断文件类型进行读取
 while (type != XmlPullParser.END_DOCUMENT) {
  switch (type) {
   //开始标签
   case XmlPullParser.START_TAG:
    if ("students".equals(parser.getName())) {
     list = new ArrayList<>();
    } else if ("student".equals(parser.getName())) {
     student = new Student();
    } else if ("name".equals(parser.getName())) {
     //获取sex属性
     String sex = parser.getAttributeValue(null,"sex");
     student.setSex(sex);
     //获取name值
     String name = parser.nextText();
     student.setName(name);
    } else if ("nickName".equals(parser.getName())) {
     //获取nickName值
     String nickName = parser.nextText();
     student.setNickName(nickName);
    }
    break;
   //结束标签
   case XmlPullParser.END_TAG:
    if ("student".equals(parser.getName())) {
     list.add(student);
    }
    break;
  }
  //继续往下读取标签类型
  type = parser.next();
 }
 return list;
}

public class XmlActivity extends AppCompatActivity implements View.OnClickListener {

 private TextView tv;
 private Button bt_dom, bt_sax, bt_pull;
 private XmlUtils xmlUtils;
 private List<Student> students;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_xml);

  tv = (TextView) findViewById(R.id.tv);
  bt_dom = (Button) findViewById(R.id.bt_dom);
  bt_sax = (Button) findViewById(R.id.bt_sax);
  bt_pull = (Button) findViewById(R.id.bt_pull);

  bt_dom.setOnClickListener(this);
  bt_sax.setOnClickListener(this);
  bt_pull.setOnClickListener(this);

  xmlUtils = new XmlUtils();
 }

 @Override
 public void onClick(View v) {
  switch (v.getId()) {
   case R.id.bt_dom:
    try {
     students = xmlUtils.dom2xml(getResources().getAssets().open("student.xml"));
     tv.setText(students.toString());
    } catch (Exception e) {
     e.printStackTrace();
    }
    break;
   case R.id.bt_sax:
    try {
     students = xmlUtils.sax2xml(getResources().getAssets().open("student.xml"));
     tv.setText(students.toString());
    } catch (Exception e) {
     e.printStackTrace();
    }
    break;
   case R.id.bt_pull:
    try {
     students = xmlUtils.pull2xml(getResources().getAssets().open("student.xml"));
     tv.setText(students.toString());
    } catch (Exception e) {
     e.printStackTrace();
    }
    break;
  }
 }
}