mars老师 [Android视频教学]01_20 XML解析
mar老师 [Android视频教学]01_20 XML解析
创建项目:XML
截图：
==>FileUtils.java
package mars.utils;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import android.os.Environment;
public class FileUtils {
private String SDPATH;
public String getSDPATH() {
return SDPATH;
}
public FileUtils() {
//得到当前外部存储设备的目录
// /SDCARD
SDPATH = Environment.getExternalStorageDirectory() + "/";
}
/**
* 在SD卡上创建文件
*
* @throws IOException
*/
public File creatSDFile(String fileName) throws IOException {
File file = new File(SDPATH + fileName);
file.createNewFile();
return file;
}
/**
* 在SD卡上创建目录
*
* @param dirName
*/
public File creatSDDir(String dirName) {
File dir = new File(SDPATH + dirName);
dir.mkdir();
return dir;
}
/**
* 判断SD卡上的文件夹是否存在
*/
public boolean isFileExist(String fileName){
File file = new File(SDPATH + fileName);
return file.exists();
}
/**
* 将一个InputStream里面的数据写入到SD卡中
*/
public File write2SDFromInput(String path,String fileName,InputStream input){
File file = null;
OutputStream output = null;
try{
creatSDDir(path);
file = creatSDFile(path + fileName);
output = new FileOutputStream(file);
byte buffer [] = new byte[4 * 1024];
while((input.read(buffer)) != -1){
output.write(buffer);
}
output.flush();
}
catch(Exception e){
e.printStackTrace();
}
finally{
try{
output.close();
}
catch(Exception e){
e.printStackTrace();
}
}
return file;
}
}
==>HttpDownloader.java
package mars.utils;
import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
public class HttpDownloader {
private URL url = null;
/**
* 根据URL下载文件，前提是这个文件当中的内容是文本，函数的返回值就是文件当中的内容
* 1.创建一个URL对象
* 2.通过URL对象，创建一个HttpURLConnection对象
* 3.得到InputStram
* 4.从InputStream当中读取数据
* @param urlStr
* @return
*/
public String download(String urlStr) {
StringBuffer sb = new StringBuffer();
String line = null;
BufferedReader buffer = null;
try {
// 创建一个URL对象
url = new URL(urlStr);
// 创建一个Http连接
HttpURLConnection urlConn = (HttpURLConnection) url
.openConnection();
// 使用IO流读取数据
buffer = new BufferedReader(new InputStreamReader(urlConn
.getInputStream()));
while ((line = buffer.readLine()) != null) {
sb.append(line);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
buffer.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return sb.toString();
}
/**
* 该函数返回整形 -1：代表下载文件出错 0：代表下载文件成功 1：代表文件已经存在
*/
public int downFile(String urlStr, String path, String fileName) {
InputStream inputStream = null;
try {
FileUtils fileUtils = new FileUtils();
if (fileUtils.isFileExist(path + fileName)) {
return 1;
} else {
inputStream = getInputStreamFromUrl(urlStr);
File resultFile = fileUtils.write2SDFromInput(path,fileName, inputStream);
if (resultFile == null) {
return -1;
}
}
} catch (Exception e) {
e.printStackTrace();
return -1;
} finally {
try {
inputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return 0;
}
/**
* 根据URL得到输入流
*
* @param urlStr
* @return
* @throws MalformedURLException
* @throws IOException
*/
public InputStream getInputStreamFromUrl(String urlStr)
throws MalformedURLException, IOException {
url = new URL(urlStr);
HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
InputStream inputStream = urlConn.getInputStream();
return inputStream;
}
}
==>MyContentHandler.java
package mars.xml;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
public class MyContentHandler extends DefaultHandler {
String hisname, address, money, sex, status;
String tagName;
public void startDocument() throws SAXException {
System.out.println("````````begin````````");
}
public void endDocument() throws SAXException {
System.out.println("````````end````````");
}
public void startElement(String namespaceURI, String localName,
String qName, Attributes attr) throws SAXException {
tagName = localName;
if (localName.equals("worker")) {
//获取标签的全部属性
for (int i = 0; i < attr.getLength(); i++) {
System.out.println(attr.getLocalName(i) + "=" + attr.getValue(i));
}
}
}
public void endElement(String namespaceURI, String localName, String qName)
throws SAXException {
//在workr标签解析完之后，会打印出所有得到的数据
tagName = "";
if (localName.equals("worker")) {
this.printout();
}
}
public void characters(char[] ch, int start, int length)
throws SAXException {
if (tagName.equals("name"))
hisname = new String(ch, start, length);
else if (tagName.equals("sex"))
sex = new String(ch, start, length);
else if (tagName.equals("status"))
status = new String(ch, start, length);
else if (tagName.equals("address"))
address = new String(ch, start, length);
else if (tagName.equals("money"))
money = new String(ch, start, length);
}
private void printout() {
System.out.print("name: ");
System.out.println(hisname);
System.out.print("sex: ");
System.out.println(sex);
System.out.print("status: ");
System.out.println(status);
System.out.print("address: ");
System.out.println(address);
System.out.print("money: ");
System.out.println(money);
System.out.println();
}
}
==>XMLActivity.java
package mars.xml;
import java.io.StringReader;
import javax.xml.parsers.SAXParserFactory;
import mars.utils.HttpDownloader;
import org.xml.sax.InputSource;
import org.xml.sax.XMLReader;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class XMLActitity extends Activity {
/** Called when the activity is first created. */
private Button parseButton ;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
parseButton = (Button)findViewById(R.id.parseButton);
parseButton.setOnClickListener(new ParseButtonListener());
}
class ParseButtonListener implements OnClickListener{
@Override
public void onClick(View v) {
HttpDownloader hd = new HttpDownloader();
String resultStr = hd.download("http://192.168.1.107:8081/voa1500/test.xml");
System.out.println(resultStr);
try{
//创建一个SAXParserFactory
SAXParserFactory factory = SAXParserFactory.newInstance();
XMLReader reader = factory.newSAXParser().getXMLReader();
//为XMLReader设置内容处理器
reader.setContentHandler(new MyContentHandler());
//开始解析文件
reader.parse(new InputSource(new StringReader(resultStr)));
}
catch(Exception e){
e.printStackTrace();
}
}
}
}
