HttpDownload下载文件以及复制到SDCard中
封装的两个工具类：
FileUtils.java
public class FileUtils {private String SDPATH;public String getSDPATH() {return SDPATH;}public void setSDPATH(String sDPATH) {SDPATH = sDPATH;}public FileUtils(){//得到当前外部存储设备的目录，得到的目录是/SDCARDSDPATH = Environment.getExternalStorageDirectory().getAbsolutePath()+File.separator;}/** * 在SD卡上创建文件 * @param fileName * @return * @throws IOException */public File createSDFile(String fileName) throws IOException{File file = new File(SDPATH+fileName);file.createNewFile();return file;}/** * 在SD卡创建文件 * @param fileName * @param dir * @return * @throws IOException */public File createFileInSDCard(String fileName,String dir) throws IOException{File file = new File(SDPATH+dir+File.separator+fileName);file.createNewFile();return file;}public boolean isFileExist(String fileName){File file = new File(SDPATH+fileName);return file.exists();}/** * 在SD卡上创建目录 * @param dirName * @return */public File createSDir(String dirName){File dir = new File(SDPATH+dirName);dir.mkdir();return dir;}/** * 将一个inputStream的数据写入到SD卡中 * @param path * @param fileName * @param input * @return */public File write2SDFromInput(String path,String fileName,InputStream input){File file = null;OutputStream output = null;try{createSDir(path);file = createSDFile(path+fileName);output = new FileOutputStream(file);byte buffer[] = new byte[4*1024];int temp;while((temp = input.read(buffer))!=-1){output.write(buffer,0,temp);}output.flush();}catch (Exception e) {e.printStackTrace();}finally{try {output.close();} catch (IOException e) {e.printStackTrace();}}return file; }/** * 取得目录文件名字和大小* FileInfo是一个实体类，存放fileName和fileSize的getter和setter方法 */public List<FileInfo> getFiles(String path){List<FileInfo> list = new ArrayList<FileInfo>();File file = new File(SDPATH+File.separator+path);File[] files = file.listFiles();for (int i = 0; i < files.length; i++) {FileInfo info = new FileInfo();info.setFileName(files[i].getName());info.setFileSize(files[i].length());list.add(info);}return list;}}public class HttpDownloader {private URL url = null;/** * 下载文件，前提这个文件是文本内容 * @param urlStr * @return */public String download(String urlStr){StringBuffer sb = new StringBuffer();String line = null;BufferedReader buffer = null;try{url = new URL(urlStr);HttpURLConnection conn = (HttpURLConnection) url.openConnection();buffer = new BufferedReader(new InputStreamReader(conn.getInputStream()));while((line = buffer.readLine())!=null){sb.append(line);}}catch(Exception e){e.printStackTrace();}finally{try {buffer.close();} catch (IOException e) {e.printStackTrace();}}return sb.toString();}/** * 返回-1:下载出错。返回0：成功。1：已存在 * @param urlStr * @param path * @param fileName * @return */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 file = fileUtils.write2SDFromInput(path, fileName, inputStream);if (file == null) {return -1;}}}catch(Exception e){e.printStackTrace();return -1;}finally{try {if (inputStream!=null) {inputStream.close();}} catch (IOException e) {e.printStackTrace();}}return 0;}/** * 根据url得到输入流 * @param urlStr * @return * @throws IOException */public InputStream getInputStreamFromUrl(String urlStr) throws IOException{url = new URL(urlStr);HttpURLConnection conn = (HttpURLConnection)url.openConnection();return conn.getInputStream();}}public class Download extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button b1 = (Button)findViewById(R.id.button1); b1.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {HttpDownloader down = new HttpDownloader();String content = down.download("http://192.168.1.1:8080/abc.txt");System.out.println("content:"+content);}}); Button b2 = (Button)findViewById(R.id.button2); b2.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {HttpDownloader down = new HttpDownloader();int result = down.downFile("http://192.168.1.1:8080/abc.txt", "/voa", "a1.mp3");System.out.println("result:"+result);}}); }}<uses-sdk android:minSdkVersion="4" /> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".Download" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> <uses-permission android:name="android.permission.INTERNET" /><uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />