Android,java,xml,xml读取与保存,基于Android(安卓)XML解析与保存的实现

获取XML文件的基本思路是，通过getResources().getXml()获的XML原始文件，得到XmlResourceParser对象，通过该对象来判断是文档的开头还是结尾，是某个标签的开始还是结尾，并通过一些获取属性的方法来遍历XML文件，从而访问XML文件的内容，下面是一个访问XML文件内容的例子，并将内容更显示在一个TextView上

数据写入xml:

ReadXMLTest.java

  private String WriteToString() {          XmlSerializer serializer = Xml.newSerializer();          StringWriter writer = new StringWriter();          try {              serializer.setOutput(writer);              serializer.startDocument("utf-8", true);              serializer.startTag("", "users");                serializer.startTag("", "userName");              serializer.text(txtUser.getText().toString());              serializer.endTag("", "userName");                serializer.startTag("", "userEmail");              serializer.text(txtEmail.getText().toString());              serializer.endTag("", "userEmail");                serializer.startTag("", "passWord");              serializer.text(txtPass.getText().toString());              serializer.endTag("", "passWord");                serializer.endTag("", "users");              serializer.endDocument();            } catch (IllegalArgumentException e) {              // TODO: handle exception              e.printStackTrace();          } catch (IllegalStateException e) {              // TODO: handle exception              e.printStackTrace();          } catch (IOException e) {              // TODO: handle exception              e.printStackTrace();          }          return writer.toString();      }        //将字符串保存为apk的私有文件      private boolean writeToXml(String str) {          try {                OutputStream out = openFileOutput("users.xml",MODE_PRIVATE);              OutputStreamWriter outWriter = new OutputStreamWriter(out);              try {                  outWriter.write(str);                  outWriter.close();                  out.close();                  return true;              } catch (IOException e) {                  // TODO: handle exception                  return false;              }          } catch (Exception e) {              // TODO: handle exception              return false;          }      }

调用时:

if(writeToXml(WriteToString()))

{

//成功

}

数据读取xml:

private String ReadXmlUser(String tag)      {          String re="";          DocumentBuilderFactory documentBuilderFactory;          DocumentBuilder documentBuilder;          Document document;          try {              documentBuilderFactory=DocumentBuilderFactory.newInstance();              documentBuilder=documentBuilderFactory.newDocumentBuilder();              //xml文件放到assets目录下              document=documentBuilder.parse(this.openFileInput("users.xml"));              org.w3c.dom.Element root= document.getDocumentElement();              NodeList nodeList=root.getElementsByTagName(tag);              Node nd=nodeList.item(0);              re= nd.getFirstChild().getNodeValue();          } catch (Exception e) {              // TODO: handle exception              e.printStackTrace();          }finally{              document=null;              documentBuilder=null;              documentBuilderFactory=null;          }          return re;      }

以上转载于 http://blog.csdn.net/hanjingjingpan/article/details/8812770

顺便介绍三种xml解析

XML三种常用的解析方式

public class MainActivity extends Activity implements OnClickListener {        private static final String TAG = "MainActivity";        Button Sax_praseXml, Dom_praseXml, Pull_praseXml, Write_xml;        TextView Sax_contentXml, Dom_contentXml, Pull_contentXml;        String xmlContent;        MyHandler myhandler;        List<PersonDetail> list;        InputStream inputStream;        public void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          setContentView(R.layout.main);          xmlContent = "";          Sax_praseXml = (Button) findViewById(R.id.btn_sax);          Dom_praseXml = (Button) findViewById(R.id.btn_dom);          Pull_praseXml = (Button) findViewById(R.id.btn_pull);          Sax_contentXml = (TextView) findViewById(R.id.view_sax);          Dom_contentXml = (TextView) findViewById(R.id.prase_dom);          Pull_contentXml = (TextView) findViewById(R.id.prase_pull);          Sax_praseXml.setOnClickListener(this);          Dom_praseXml.setOnClickListener(this);          Pull_praseXml.setOnClickListener(this);        }        public void onClick(View v) {          switch (v.getId()) {          case R.id.btn_sax:              inputStream = MainActivity.class.getClassLoader()                      .getResourceAsStream("test.xml");              try {                  Log.v(TAG, "-------sax");                  StringBuffer sb = new StringBuffer();                  list = SAXpraseTransiaction.SaxPrase(inputStream);                  for (PersonDetail tail : list) {                      sb.append(tail.toString() + "\n");                  }                  Sax_contentXml.setText("SaxResult:" + sb.toString());                  Log.v(TAG, "" + "----------------------" + sb.toString());              } catch (Exception E) {                  Log.v(TAG, "" + "----------------------解析失败");              }              break;          case R.id.btn_dom:              inputStream = MainActivity.class.getClassLoader()                      .getResourceAsStream("test.xml");              try {                  Log.v(TAG, "-------DOM");                  StringBuffer sbDOM = new StringBuffer();                  list = DomPraserTransaction.getPraserList(inputStream);                  for (PersonDetail tail : list) {                      sbDOM.append(tail.toString() + "\n");                  }                  Dom_contentXml.setText("DOMResult:" + sbDOM.toString());                  Log.v(TAG, "" + "----------------------" + sbDOM.toString());              } catch (Exception E) {                  Log.v(TAG, "" + "----------------------解析失败");              }              break;          case R.id.btn_pull:              inputStream = MainActivity.class.getClassLoader()                      .getResourceAsStream("test.xml");              try {                  Log.v(TAG, "-------PULL");                  StringBuffer sbPULL = new StringBuffer();                  list = PullPraserTransaction.GetResultList(inputStream);                  for (PersonDetail tail : list) {                      sbPULL.append(tail.toString() + "\n");                  }                  Pull_contentXml.setText("PULLResult:" + sbPULL.toString());                  Log.v(TAG, "" + "----------------------" + sbPULL.toString());              } catch (Exception E) {                  Log.v(TAG, "" + "----------------------解析失败");              }              break;          }      }    /**   * 实用于文件比较小的Xml解析,简单实用 2011/9/29   *    * @author:1314hwl   *    */  public class DomPraserTransaction {        public static List<PersonDetail> getPraserList(InputStream inputStream) {          List<PersonDetail> Resultlist = null;          PersonDetail Person = null;          XmlPullParser pullpraser = Xml.newPullParser();          try {              pullpraser.setInput(inputStream, "UTF-8");              int eventtype = pullpraser.getEventType();              while (eventtype != XmlPullParser.END_DOCUMENT) {                  switch (eventtype) {                  case XmlPullParser.START_DOCUMENT:                      Resultlist = new ArrayList<PersonDetail>();                      break;                  case XmlPullParser.START_TAG:                      if ("person".equals(pullpraser.getName())) {                          Person = new PersonDetail();                          Person.setId(new Integer(pullpraser                                  .getAttributeValue(0)));                      } else if (Person != null) {                          if ("name".equals(pullpraser.getName())) {                              Person.setName(pullpraser.nextText());                          } else if ("age".equals(pullpraser.getName())) {                              Person.setAge(new String(pullpraser.nextText()));                          }                      }                      break;                  case XmlPullParser.END_TAG:                      if ("person".equals(pullpraser.getName()) && Person != null) {                          Resultlist.add(Person);                          Person = null;                      }                      break;                  }                  eventtype = pullpraser.next();              }          } catch (Exception e) {              e.printStackTrace();          }            try {              inputStream.close();          } catch (IOException e) {              e.printStackTrace();          }          return Resultlist;        }  }    /**   * pull解析XML pull写入XML   *    * @author 1314hwl 2011/9/29   *    */    public class PullPraserTransaction {        public static List<PersonDetail> GetResultList(InputStream inputStream)              throws Exception {            List<PersonDetail> Resultlist = new ArrayList<PersonDetail>();            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();            DocumentBuilder builder = factory.newDocumentBuilder();            Document document = builder.parse(inputStream);            Element element = document.getDocumentElement();            NodeList nodes = element.getElementsByTagName("person");            int len = nodes.getLength();            for (int i = 0; i < len; i++) {              Element personElement = (Element) nodes.item(i);              PersonDetail person = new PersonDetail();              person.setId(new Integer(personElement.getAttribute("id")));              NodeList childNodes = personElement.getChildNodes();              for (int y = 0; y < childNodes.getLength(); y++) {                  Node childNode = (Node) childNodes.item(y);                  if (childNode.getNodeType() == Node.ELEMENT_NODE) {                      Element childElement = (Element) childNode;                      if ("name".equals(childElement.getNodeName())) {                          person.setName(childElement.getFirstChild()                                  .getNodeValue());                      }                      if ("age".equals(childElement.getNodeName())) {                          person.setAge(childElement.getFirstChild()                                  .getNodeValue());                      }                  }              }              Resultlist.add(person);          }          inputStream.close();          return Resultlist;      }  }    /**   * @author 1314hwl SAX解析 2011/9/29   */  public class SAXpraseTransiaction {        public static List<PersonDetail> SaxPrase(InputStream inputStream) {            SAXParserFactory factory = SAXParserFactory.newInstance();//解析工厂          // try {          // SAXParser saxparser=factory.newSAXParser(); //解析器对象          //          // MyHandler myhandler=new MyHandler();          //          // saxparser.parse(inputStream, myhandler);            //          // inputStream.close();          // } catch (Exception e) {          //          // } 这里两种方式：SAXParser or XMLReader 都可以          MyHandler myhandler = new MyHandler();          try {                XMLReader xmlreader = factory.newSAXParser().getXMLReader();//实现一个XMLReader              xmlreader.setContentHandler(myhandler); //defualthandler              xmlreader.parse(new InputSource(inputStream));//要解析的流加入解析中          } catch (Exception e) {              e.printStackTrace();          }          try {              inputStream.close();          } catch (IOException e) {              e.printStackTrace();          }          return myhandler.resultList();        }    }    **   * SAX解析的defaultHandler   *    * @author 1314hwl 2011/9/29   */  public class MyHandler extends DefaultHandler {      private static final String TAG = "MyHandler";      String name, age;      String tagname;      PersonDetail Person;      List<PersonDetail> personList = null;        public MyHandler() {          super();          personList = new ArrayList<PersonDetail>();      }        public void characters(char[] ch, int start, int length)              throws SAXException {          super.characters(ch, start, length);          if (Person != null) {              String content = new String(ch, start, length);              if ("name".equals(tagname)) {                  Person.setName(content);              } else if ("age".equals(tagname)) {                  Person.setAge(content);              }          }      }        public void endDocument() throws SAXException {          super.endDocument();          Log.v(TAG, "解析结束");      }        public void endElement(String uri, String localName, String qName)              throws SAXException {          super.endElement(uri, localName, qName);          if (localName.equals("person") && Person != null) {              personList.add(Person);              Person = null;          }          tagname=null;      }        public void startDocument() throws SAXException {          super.startDocument();          Log.v(TAG, "解析开始");        }        public void startElement(String uri, String localName, String qName,              Attributes attributes) throws SAXException {          super.startElement(uri, localName, qName, attributes);          Log.v("startElement", localName);          tagname = localName;          if (localName.equals("person")) {              Person = new PersonDetail();              Person.setId(new Integer(attributes.getValue(0)));          }              }        public List<PersonDetail> resultList() {          return personList;      }    }    public class PersonDetail {      String name, age;        int id;        public int getId() {          return id;      }        public void setId(int id) {          this.id = id;      }        public PersonDetail(int id, String name, String age) {          super();          this.id = id;          this.name = name;          this.age = age;      }        public PersonDetail() {          super();      }        public String getName() {          return name;      }        public void setName(String name) {          this.name = name;      }        public String getAge() {          return age;      }        public void setAge(String age) {          this.age = age;      }        public String toString() {          return "person [id=" + id + ", name=" + name + ", age=" + age + "]";      }    }

以上转载于 http://blog.csdn.net/hwl1314/article/details/6835493#1536434-tsina-1-56553-66a1f5d8f89e9ad52626f6f40fdeadaa

以及详解Java反射机制实例

import java.lang.reflect.*;         public class ReflectTester {         public Object copy(Object object) throws Exception {             // 获得对象的类型             Class classType = object.getClass();             System.out.println("Class:" + classType.getName());             // 通过默认构造方法创建一个新的对象             Object objectCopy = classType.getConstructor(new Class[] {})                     .newInstance(new Object[] {});             // 获得对象的所有属性             Field fields[] = classType.getDeclaredFields();             for (int i = 0; i < fields.length; i++) {                 Field field = fields[i];                 String fieldName = field.getName();                 String firstLetter = fieldName.substring(0, 1).toUpperCase();                 // 获得和属性对应的getXXX()方法的名字                 String getMethodName = "get" + firstLetter + fieldName.substring(1);                 // 获得和属性对应的setXXX()方法的名字                 String setMethodName = "set" + firstLetter + fieldName.substring(1);                 // 获得和属性对应的getXXX()方法                 Method getMethod = classType.getMethod(getMethodName,                         new Class[] {});                 // 获得和属性对应的setXXX()方法                 Method setMethod = classType.getMethod(setMethodName,                         new Class[] { field.getType() });                 // 调用原对象的getXXX()方法                 Object value = getMethod.invoke(object, new Object[] {});                 System.out.println(fieldName + ":" + value);                 // 调用复制对象的setXXX()方法                 setMethod.invoke(objectCopy, new Object[] { value });             }             return objectCopy;         }             public static void main(String[] args) throws Exception {             Customer customer = new Customer("Tom", 21);             customer.setId(new Long(1));             Customer customerCopy = (Customer) new ReflectTester().copy(customer);             System.out.println("Copy information:" + customerCopy.getName() + " "                    + customerCopy.getAge());         }     }         class Customer { // Customer类是一个JavaBean         private Long id;         private String name;         private int age;             public Customer() {         }             public Customer(String name, int age) {             this.name = name;             this.age = age;         }             public Long getId() {             return id;         }             public void setId(Long id) {             this.id = id;         }             public String getName() {             return name;         }             public void setName(String name) {             this.name = name;         }             public int getAge() {             return age;         }             public void setAge(int age) {             this.age = age;         }     }

反射转载于 http://developer.51cto.com/art/201103/248118.htm#585532-tsina-1-63092-7e393678b940a4d55500bf3feae3d2e9

阅读完以上的内容

我们的第一个方法 WriteToString() 就可以通过反射直接写出，不需要每次都写好多属性

举例说明：Product.Java

private String name;private String price;public String getName() {return name;}public void setName(String name) {this.name = name;}public String getPrice() {return price;}public void setPrice(String price) {this.price = price;}

Test.java

public static void main(String[] args) throws Exception  {List<Product> plist = new ArrayList<Product>();Product p1=  new Product();p1.setName("空气净化器1");p1.setPrice("3799");plist.add(p1);Product p2=  new Product();p2.setName("空气净化器2");p2.setPrice("3799");plist.add(p2);produceXml(Product.class , plist);}public static String produceXml(Class clazz,List plist) throws Exception{ System.out.println("<" +clazz.getName().toLowerCase()+"s" +">");  for(Object o:plist){   System.out.println( "<" +clazz.getName().toLowerCase()+">"); for(int i=0;i< clazz.getDeclaredFields().length;i++){ System.out.print("<" + clazz.getDeclaredFields()[i].getName() +">");                      for(int j = 0; j < Product.class.getDeclaredMethods().length; j++) {           if (  ("get"+clazz.getDeclaredFields()[i].getName().substring(0,1).toUpperCase()+( clazz.getDeclaredFields()[i].getName().substring(1)) ).equals( clazz.getDeclaredMethods()[j].getName() )){                    Method getMethod = clazz.getMethod(clazz.getDeclaredMethods()[j].getName(),  new Class[]{});          Object result = getMethod.invoke( o, new Object[] {});           System.out.print( result.toString());                }          }                  System.out.println("</"+ clazz.getDeclaredFields()[i].getName() +">");           } System.out.println( "</"+clazz.getName().toLowerCase()+">"); }  System.out.println( "</"+clazz.getName().toLowerCase()+"s"+">"); return null; }

运行结果：

<products><product><name>空气净化器1</name><price>3799</price></product><product><name>空气净化器2</name><price>3799</price></product></products>

System.out.println( "</"+ ……+">"); 替换成xmlSerializer.endTag(null, ……);就ok了哦！

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