Android常用的工具类-收藏用

一. 检查网络是否可用.

ConnectionUtil.java

import android.app.AlertDialog;import android.content.Context;import android.content.DialogInterface;import android.net.ConnectivityManager;import android.net.NetworkInfo;public class ConnectionUtil {/*** 检查网络是否可用* @param context应用程序的上下文对象* @return*/public static boolean isNetworkAvailable(Context context) {ConnectivityManager connectivity = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);//获取系统网络连接管理器if (connectivity == null) {//如果网络管理器为nullreturn false;  //返回false表明网络无法连接} else {NetworkInfo[] info = connectivity.getAllNetworkInfo();//获取所有的网络连接对象if (info != null) {//网络信息不为null时for (int i = 0; i < info.length; i++) {//遍历网路连接对象if (info[i].isConnected()) {//当有一个网络连接对象连接上网络时return true;  //返回true表明网络连接正常} }}}return false;  }public static void httpTest(final Context ctx,String title,String msg) {if (!isNetworkAvailable(ctx)) {AlertDialog.Builder builders = new AlertDialog.Builder(ctx);builders.setTitle(title);builders.setMessage(msg);builders.setPositiveButton(android.R.string.ok,new DialogInterface.OnClickListener() {public void onClick(DialogInterface dialog, int which) {//alert.dismiss();}});AlertDialog alert = builders.create();alert.show();}}}

二.读取流文件.

FileStreamTool.java

import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.PushbackInputStream;public class FileStreamTool {public static void save(File file, byte[] data) throws Exception {FileOutputStream outStream = new FileOutputStream(file);outStream.write(data);outStream.close();} public static String readLine(PushbackInputStream in) throws IOException {char buf[] = new char[128];int room = buf.length;int offset = 0;int c;loop: while (true) {switch (c = in.read()) {case -1:case '\n':break loop;case '\r':int c2 = in.read();if ((c2 != '\n') && (c2 != -1)) in.unread(c2);break loop;default:if (--room < 0) {char[] lineBuffer = buf;buf = new char[offset + 128];   room = buf.length - offset - 1;   System.arraycopy(lineBuffer, 0, buf, 0, offset);  }buf[offset++] = (char) c;break;}}if ((c == -1) && (offset == 0)) return null;return String.copyValueOf(buf, 0, offset);} /*** 读取流* @param inStream* @return 字节数组* @throws Exception*/public static byte[] readStream(InputStream inStream) throws Exception{ByteArrayOutputStream outSteam = new ByteArrayOutputStream();byte[] buffer = new byte[1024];int len = -1;while( (len=inStream.read(buffer)) != -1){outSteam.write(buffer, 0, len);}outSteam.close();inStream.close();return outSteam.toByteArray();}}

三.文件断点续传.

MainActivity.java

import java.io.File;import java.io.OutputStream;import java.io.PushbackInputStream;import java.io.RandomAccessFile;import java.net.Socket;import cn.itcast.service.UploadLogService;import cn.itcast.utils.StreamTool;import android.app.Activity;import android.os.Bundle;import android.os.Environment;import android.os.Handler;import android.os.Message;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.ProgressBar;import android.widget.TextView;import android.widget.Toast;public class MainActivity extends Activity {    private EditText filenameText;    private TextView resultView;    private ProgressBar uploadbar;    private UploadLogService service;    private Handler handler = new Handler(){@Overridepublic void handleMessage(Message msg) {uploadbar.setProgress(msg.getData().getInt("length"));float num = (float)uploadbar.getProgress() / (float)uploadbar.getMax();int result = (int)(num * 100);resultView.setText(result + "%");if(uploadbar.getProgress() == uploadbar.getMax()){Toast.makeText(MainActivity.this, R.string.success, 1).show();}}    };        @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);                service =  new UploadLogService(this);        filenameText = (EditText)findViewById(R.id.filename);        resultView = (TextView)findViewById(R.id.result);        uploadbar = (ProgressBar)findViewById(R.id.uploadbar);        Button button = (Button)findViewById(R.id.button);        button.setOnClickListener(new View.OnClickListener() {public void onClick(View v) {String filename = filenameText.getText().toString();if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){File file = new File(Environment.getExternalStorageDirectory(), filename);if(file.exists()){uploadbar.setMax((int)file.length());uploadFile(file);}else{Toast.makeText(MainActivity.this, R.string.notexsit, 1).show();}}else{Toast.makeText(MainActivity.this, R.string.sdcarderror, 1).show();}}});    }private void uploadFile(final File file) {new Thread(new Runnable() {public void run() {try {String sourceid = service.getBindId(file);Socket socket = new Socket("192.168.1.100", 7878);//根据IP地址和端口不同更改           OutputStream outStream = socket.getOutputStream();            String head = "Content-Length="+ file.length() + ";filename="+ file.getName()              + ";sourceid="+(sourceid!=null ? sourceid : "")+"\r\n";           outStream.write(head.getBytes());                      PushbackInputStream inStream = new PushbackInputStream(socket.getInputStream());String response = StreamTool.readLine(inStream);           String[] items = response.split(";");String responseSourceid = items[0].substring(items[0].indexOf("=")+1);String position = items[1].substring(items[1].indexOf("=")+1);if(sourceid==null){//如果是第一次上传文件，在数据库中不存在该文件所绑定的资源id，入库service.save(responseSourceid, file);}RandomAccessFile fileOutStream = new RandomAccessFile(file, "r");fileOutStream.seek(Integer.valueOf(position));byte[] buffer = new byte[1024];int len = -1;int length = Integer.valueOf(position);while( (len = fileOutStream.read(buffer)) != -1){outStream.write(buffer, 0, len);length += len;//累加已经上传的数据长度Message msg = new Message();msg.getData().putInt("length", length);handler.sendMessage(msg);}if(length == file.length()) service.delete(file);fileOutStream.close();outStream.close();           inStream.close();           socket.close();       } catch (Exception e) {                             Toast.makeText(MainActivity.this, R.string.error, 1).show();       }}}).start();}}

DBOpenHelper.java

import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;public class DBOpenHelper extends SQLiteOpenHelper {public DBOpenHelper(Context context) {super(context, "itcast.db", null, 1);}@Overridepublic void onCreate(SQLiteDatabase db) {db.execSQL("CREATE TABLE IF NOT EXISTS uploadlog (_id integer primary key autoincrement, path varchar(20), sourceid varchar(20))");}@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {// TODO Auto-generated method stub}}

UpLoadLogService.java

import java.io.File;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;public class UploadLogService {private DBOpenHelper dbOpenHelper;public UploadLogService(Context context){dbOpenHelper = new DBOpenHelper(context);}public String getBindId(File file){SQLiteDatabase db = dbOpenHelper.getReadableDatabase();Cursor cursor = db.rawQuery("select sourceid from uploadlog where path=?", new String[]{file.getAbsolutePath()});if(cursor.moveToFirst()){return cursor.getString(0);}return null;}public void save(String sourceid, File file){SQLiteDatabase db = dbOpenHelper.getWritableDatabase();db.execSQL("insert into uploadlog(path,sourceid) values(?,?)", new Object[]{file.getAbsolutePath(), sourceid});}public void delete(File file){SQLiteDatabase db = dbOpenHelper.getWritableDatabase();db.execSQL("delete from uploadlog where path=?", new Object[]{file.getAbsolutePath()});} }

四.多线程断点续传.

MainActivity.java

import java.io.File;import cn.itcast.net.download.DownloadProgressListener;import cn.itcast.net.download.FileDownloader;import android.app.Activity;import android.os.Bundle;import android.os.Environment;import android.os.Handler;import android.os.Message;import android.view.View;import android.widget.Button;import android.widget.EditText;import android.widget.ProgressBar;import android.widget.TextView;import android.widget.Toast;public class MainActivity extends Activity {    private EditText pathText;    private TextView resultView;    private Button downloadButton;    private Button stopbutton;    private ProgressBar progressBar;    //hanlder的作用是用于往创建Hander对象所在的线程所绑定的消息队列发送消息    private Handler handler = new UIHander();        private final class UIHander extends Handler{public void handleMessage(Message msg) {switch (msg.what) {case 1:int size = msg.getData().getInt("size");progressBar.setProgress(size);float num = (float)progressBar.getProgress() / (float)progressBar.getMax();int result = (int)(num * 100);resultView.setText(result+ "%");if(progressBar.getProgress() == progressBar.getMax()){Toast.makeText(getApplicationContext(), R.string.success, 1).show();}break;case -1:Toast.makeText(getApplicationContext(), R.string.error, 1).show();break;}}    }        @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);                pathText = (EditText) this.findViewById(R.id.path);        resultView = (TextView) this.findViewById(R.id.resultView);        downloadButton = (Button) this.findViewById(R.id.downloadbutton);        stopbutton = (Button) this.findViewById(R.id.stopbutton);        progressBar = (ProgressBar) this.findViewById(R.id.progressBar);        ButtonClickListener listener = new ButtonClickListener();        downloadButton.setOnClickListener(listener);        stopbutton.setOnClickListener(listener);    }    private final class ButtonClickListener implements View.OnClickListener{public void onClick(View v) {switch (v.getId()) {case R.id.downloadbutton:String path = pathText.getText().toString();if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){File saveDir = Environment.getExternalStorageDirectory();download(path, saveDir);}else{Toast.makeText(getApplicationContext(), R.string.sdcarderror, 1).show();}downloadButton.setEnabled(false);stopbutton.setEnabled(true);break;case R.id.stopbutton:exit();downloadButton.setEnabled(true);stopbutton.setEnabled(false);break;}}/*由于用户的输入事件(点击button, 触摸屏幕....)是由主线程负责处理的，如果主线程处于工作状态，此时用户产生的输入事件如果没能在5秒内得到处理，系统就会报“应用无响应”错误。所以在主线程里不能执行一件比较耗时的工作，否则会因主线程阻塞而无法处理用户的输入事件，导致“应用无响应”错误的出现。耗时的工作应该在子线程里执行。*/private DownloadTask task;/*** 退出下载*/public void exit(){if(task!=null) task.exit();}private void download(String path, File saveDir) {//运行在主线程task = new DownloadTask(path, saveDir);new Thread(task).start();}/** UI控件画面的重绘(更新)是由主线程负责处理的，如果在子线程中更新UI控件的值，更新后的值不会重绘到屏幕上* 一定要在主线程里更新UI控件的值，这样才能在屏幕上显示出来，不能在子线程中更新UI控件的值*/private final class DownloadTask implements Runnable{private String path;private File saveDir;private FileDownloader loader;public DownloadTask(String path, File saveDir) {this.path = path;this.saveDir = saveDir;}/*** 退出下载*/public void exit(){if(loader!=null) loader.exit();}public void run() {try {loader = new FileDownloader(getApplicationContext(), path, saveDir, 3);progressBar.setMax(loader.getFileSize());//设置进度条的最大刻度loader.download(new DownloadProgressListener() {public void onDownloadSize(int size) {Message msg = new Message();msg.what = 1;msg.getData().putInt("size", size);handler.sendMessage(msg);}});} catch (Exception e) {e.printStackTrace();handler.sendMessage(handler.obtainMessage(-1));}} }    }        }

DBOpenHelper.java

import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;public class DBOpenHelper extends SQLiteOpenHelper {private static final String DBNAME = "itcast.db";private static final int VERSION = 1;public DBOpenHelper(Context context) {super(context, DBNAME, null, VERSION);}@Overridepublic void onCreate(SQLiteDatabase db) {db.execSQL("CREATE TABLE IF NOT EXISTS filedownlog (id integer primary key autoincrement, downpath varchar(100), threadid INTEGER, downlength INTEGER)");}@Overridepublic void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {db.execSQL("DROP TABLE IF EXISTS filedownlog");onCreate(db);}}

FileService.java

import java.util.HashMap;import java.util.Map;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;/** * 业务bean * */public class FileService {private DBOpenHelper openHelper;public FileService(Context context) {openHelper = new DBOpenHelper(context);}/*** 获取每条线程已经下载的文件长度* @param path* @return*/public Map<Integer, Integer> getData(String path){SQLiteDatabase db = openHelper.getReadableDatabase();Cursor cursor = db.rawQuery("select threadid, downlength from filedownlog where downpath=?", new String[]{path});Map<Integer, Integer> data = new HashMap<Integer, Integer>();while(cursor.moveToNext()){data.put(cursor.getInt(0), cursor.getInt(1));}cursor.close();db.close();return data;}/*** 保存每条线程已经下载的文件长度* @param path* @param map*/public void save(String path,  Map<Integer, Integer> map){//int threadid, int positionSQLiteDatabase db = openHelper.getWritableDatabase();db.beginTransaction();try{for(Map.Entry<Integer, Integer> entry : map.entrySet()){db.execSQL("insert into filedownlog(downpath, threadid, downlength) values(?,?,?)",new Object[]{path, entry.getKey(), entry.getValue()});}db.setTransactionSuccessful();}finally{db.endTransaction();}db.close();}/*** 实时更新每条线程已经下载的文件长度* @param path* @param map*/public void update(String path, int threadId, int pos){SQLiteDatabase db = openHelper.getWritableDatabase();db.execSQL("update filedownlog set downlength=? where downpath=? and threadid=?",new Object[]{pos, path, threadId});db.close();}/*** 当文件下载完成后，删除对应的下载记录* @param path*/public void delete(String path){SQLiteDatabase db = openHelper.getWritableDatabase();db.execSQL("delete from filedownlog where downpath=?", new Object[]{path});db.close();}}

DownloadProgressListener.java

public interface DownloadProgressListener {public void onDownloadSize(int size);}

DownLoadThread.java

import java.io.File;import java.io.InputStream;import java.io.RandomAccessFile;import java.net.HttpURLConnection;import java.net.URL;import android.util.Log;public class DownloadThread extends Thread {private static final String TAG = "DownloadThread";private File saveFile;private URL downUrl;private int block;/* 下载开始位置  */private int threadId = -1;private int downLength;private boolean finish = false;private FileDownloader downloader;public DownloadThread(FileDownloader downloader, URL downUrl, File saveFile, int block, int downLength, int threadId) {this.downUrl = downUrl;this.saveFile = saveFile;this.block = block;this.downloader = downloader;this.threadId = threadId;this.downLength = downLength;}@Overridepublic void run() {if(downLength < block){//未下载完成try {HttpURLConnection http = (HttpURLConnection) downUrl.openConnection();http.setConnectTimeout(5 * 1000);http.setRequestMethod("GET");http.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*");http.setRequestProperty("Accept-Language", "zh-CN");http.setRequestProperty("Referer", downUrl.toString()); http.setRequestProperty("Charset", "UTF-8");int startPos = block * (threadId - 1) + downLength;//开始位置int endPos = block * threadId -1;//结束位置http.setRequestProperty("Range", "bytes=" + startPos + "-"+ endPos);//设置获取实体数据的范围http.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");http.setRequestProperty("Connection", "Keep-Alive");InputStream inStream = http.getInputStream();byte[] buffer = new byte[1024];int offset = 0;print("Thread " + this.threadId + " start download from position "+ startPos);RandomAccessFile threadfile = new RandomAccessFile(this.saveFile, "rwd");threadfile.seek(startPos);while (!downloader.getExit() && (offset = inStream.read(buffer, 0, 1024)) != -1) {threadfile.write(buffer, 0, offset);downLength += offset;downloader.update(this.threadId, downLength);downloader.append(offset);}threadfile.close();inStream.close();print("Thread " + this.threadId + " download finish");this.finish = true;} catch (Exception e) {this.downLength = -1;print("Thread "+ this.threadId+ ":"+ e);}}}private static void print(String msg){Log.i(TAG, msg);}/*** 下载是否完成* @return*/public boolean isFinish() {return finish;}/*** 已经下载的内容大小* @return 如果返回值为-1,代表下载失败*/public long getDownLength() {return downLength;}}

FileDownloader.java

import java.io.File;import java.io.RandomAccessFile;import java.net.HttpURLConnection;import java.net.URL;import java.util.LinkedHashMap;import java.util.Map;import java.util.UUID;import java.util.concurrent.ConcurrentHashMap;import java.util.regex.Matcher;import java.util.regex.Pattern;import cn.itcast.service.FileService;import android.content.Context;import android.util.Log;/** * 文件下载器 * try {FileDownloader loader = new FileDownloader(context, "http://browse.babasport.com/ejb3/ActivePort.exe",new File("D:\\androidsoft\\test"), 2);loader.getFileSize();//得到文件总大小loader.download(new DownloadProgressListener(){public void onDownloadSize(int size) {print("已经下载："+ size);} });} catch (Exception e) {e.printStackTrace();} */public class FileDownloader {private static final String TAG = "FileDownloader";private Context context;private FileService fileService;/* 停止下载 */private boolean exit;/* 已下载文件长度 */private int downloadSize = 0;/* 原始文件长度 */private int fileSize = 0;/* 线程数 */private DownloadThread[] threads;/* 本地保存文件 */private File saveFile;/* 缓存各线程下载的长度*/private Map<Integer, Integer> data = new ConcurrentHashMap<Integer, Integer>();/* 每条线程下载的长度 */private int block;/* 下载路径  */private String downloadUrl;/*** 获取线程数*/public int getThreadSize() {return threads.length;}/*** 退出下载*/public void exit(){this.exit = true;}public boolean getExit(){return this.exit;}/*** 获取文件大小* @return*/public int getFileSize() {return fileSize;}/*** 累计已下载大小* @param size*/protected synchronized void append(int size) {downloadSize += size;}/*** 更新指定线程最后下载的位置* @param threadId 线程id* @param pos 最后下载的位置*/protected synchronized void update(int threadId, int pos) {this.data.put(threadId, pos);this.fileService.update(this.downloadUrl, threadId, pos);}/*** 构建文件下载器* @param downloadUrl 下载路径* @param fileSaveDir 文件保存目录* @param threadNum 下载线程数*/public FileDownloader(Context context, String downloadUrl, File fileSaveDir, int threadNum) {try {this.context = context;this.downloadUrl = downloadUrl;fileService = new FileService(this.context);URL url = new URL(this.downloadUrl);if(!fileSaveDir.exists()) fileSaveDir.mkdirs();this.threads = new DownloadThread[threadNum];HttpURLConnection conn = (HttpURLConnection) url.openConnection();conn.setConnectTimeout(5*1000);conn.setRequestMethod("GET");conn.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*");conn.setRequestProperty("Accept-Language", "zh-CN");conn.setRequestProperty("Referer", downloadUrl); conn.setRequestProperty("Charset", "UTF-8");conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");conn.setRequestProperty("Connection", "Keep-Alive");conn.connect();printResponseHeader(conn);if (conn.getResponseCode()==200) {this.fileSize = conn.getContentLength();//根据响应获取文件大小if (this.fileSize <= 0) throw new RuntimeException("Unkown file size ");String filename = getFileName(conn);//获取文件名称this.saveFile = new File(fileSaveDir, filename);//构建保存文件Map<Integer, Integer> logdata = fileService.getData(downloadUrl);//获取下载记录if(logdata.size()>0){//如果存在下载记录for(Map.Entry<Integer, Integer> entry : logdata.entrySet())data.put(entry.getKey(), entry.getValue());//把各条线程已经下载的数据长度放入data中}if(this.data.size()==this.threads.length){//下面计算所有线程已经下载的数据总长度for (int i = 0; i < this.threads.length; i++) {this.downloadSize += this.data.get(i+1);}print("已经下载的长度"+ this.downloadSize);}//计算每条线程下载的数据长度this.block = (this.fileSize % this.threads.length)==0? this.fileSize / this.threads.length : this.fileSize / this.threads.length + 1;}else{throw new RuntimeException("server no response ");}} catch (Exception e) {print(e.toString());throw new RuntimeException("don't connection this url");}}/*** 获取文件名*/private String getFileName(HttpURLConnection conn) {String filename = this.downloadUrl.substring(this.downloadUrl.lastIndexOf('/') + 1);if(filename==null || "".equals(filename.trim())){//如果获取不到文件名称for (int i = 0;; i++) {String mine = conn.getHeaderField(i);if (mine == null) break;if("content-disposition".equals(conn.getHeaderFieldKey(i).toLowerCase())){Matcher m = Pattern.compile(".*filename=(.*)").matcher(mine.toLowerCase());if(m.find()) return m.group(1);}}filename = UUID.randomUUID()+ ".tmp";//默认取一个文件名}return filename;}/***  开始下载文件* @param listener 监听下载数量的变化,如果不需要了解实时下载的数量,可以设置为null* @return 已下载文件大小* @throws Exception*/public int download(DownloadProgressListener listener) throws Exception{try {RandomAccessFile randOut = new RandomAccessFile(this.saveFile, "rw");if(this.fileSize>0) randOut.setLength(this.fileSize);randOut.close();URL url = new URL(this.downloadUrl);if(this.data.size() != this.threads.length){//如果原先未曾下载或者原先的下载线程数与现在的线程数不一致this.data.clear();for (int i = 0; i < this.threads.length; i++) {this.data.put(i+1, 0);//初始化每条线程已经下载的数据长度为0}this.downloadSize = 0;}for (int i = 0; i < this.threads.length; i++) {//开启线程进行下载int downLength = this.data.get(i+1);if(downLength < this.block && this.downloadSize<this.fileSize){//判断线程是否已经完成下载,否则继续下载this.threads[i] = new DownloadThread(this, url, this.saveFile, this.block, this.data.get(i+1), i+1);this.threads[i].setPriority(7);this.threads[i].start();}else{this.threads[i] = null;}}fileService.delete(this.downloadUrl);//如果存在下载记录，删除它们，然后重新添加fileService.save(this.downloadUrl, this.data);boolean notFinish = true;//下载未完成while (notFinish) {// 循环判断所有线程是否完成下载Thread.sleep(900);notFinish = false;//假定全部线程下载完成for (int i = 0; i < this.threads.length; i++){if (this.threads[i] != null && !this.threads[i].isFinish()) {//如果发现线程未完成下载notFinish = true;//设置标志为下载没有完成if(this.threads[i].getDownLength() == -1){//如果下载失败,再重新下载this.threads[i] = new DownloadThread(this, url, this.saveFile, this.block, this.data.get(i+1), i+1);this.threads[i].setPriority(7);this.threads[i].start();}}} if(listener!=null) listener.onDownloadSize(this.downloadSize);//通知目前已经下载完成的数据长度}if(downloadSize == this.fileSize) fileService.delete(this.downloadUrl);//下载完成删除记录} catch (Exception e) {print(e.toString());throw new Exception("file download error");}return this.downloadSize;}/*** 获取Http响应头字段* @param http* @return*/public static Map<String, String> getHttpResponseHeader(HttpURLConnection http) {Map<String, String> header = new LinkedHashMap<String, String>();for (int i = 0;; i++) {String mine = http.getHeaderField(i);if (mine == null) break;header.put(http.getHeaderFieldKey(i), mine);}return header;}/*** 打印Http头字段* @param http*/public static void printResponseHeader(HttpURLConnection http){Map<String, String> header = getHttpResponseHeader(http);for(Map.Entry<String, String> entry : header.entrySet()){String key = entry.getKey()!=null ? entry.getKey()+ ":" : "";print(key+ entry.getValue());}}private static void print(String msg){Log.i(TAG, msg);}}