안 드 로 이 드 네 이 티 브 구현 다 중 스 레 드 정지점 인 스 턴 스 코드 다운로드
본문 을 통 해 당신 은 배 울 수 있 습 니 다.
데 모 는 TV 에서 실행 되 고 있 으 니 그림 에 표 시 된 문 제 는 고민 하지 마 세 요.
파일 다운로드 데모 가 완료 되 었 습 니 다.업로드 와 설명 이 없습니다.오늘 보 여 드 리 고 설명해 드 리 겠 습 니 다.순수한 것 으로 파일 을 다운로드 할 수 있 습 니 다.안 드 로 이 드 의 기본 적 인 문 제 를 더 많이 이해 해 주 셨 으 면 합 니 다.
우리 의 사고방식:하나의 데이터베이스,두 개의 테이블,하 나 는 네트워크 데 이 터 를 저장 하 는 데 사용 되 고,하 나 는 로 컬 다운로드 의 진 도 를 저장 하 는 데 사용 된다.다운로드 단 추 를 눌 렀 을 때 DownloadService 를 시작 하여 비교 한 후 다운로드 합 니 다.
데모 의 디 렉 터 리 구조 부터 살 펴 보 겠 습 니 다.
모든 절 차 는 코드 에 매우 상세 한 설명 이 있 습 니 다.반드시 코드 를 봐 야 합 니 다(다음은 추출 한 몇 가지 중요 한 설명 입 니 다)!
데이터베이스 구축 및 DAO
/**
* Created by Administrator on 2017/3/6 0006.
*/
public class DownLoadDBHelper extends SQLiteOpenHelper {
/**
* DownLoadDBHelper ，
*
*
* ：
* download_info
* localdownload_info
*
*/
public static String DATABASE_NAME = "downloadFILES.db";
public static String TABLE_DOWNLOAD_INFO = "download_info";
public static String TABLE_LOCALDOWNLOAD_INFO = "localdownload_info";
private static int version = 1;
public DownLoadDBHelper(Context context) {
super(context, DATABASE_NAME, null, version);
}
@Override
public void onCreate(SQLiteDatabase db) {
/* , , sqlite */
db.execSQL("create table " + TABLE_DOWNLOAD_INFO + "(" + "id integer PRIMARY KEY AUTOINCREMENT," +
"thread_id integer," + "start_position integer," + "end_position integer," + " completed_size integer," + "url varchar(100))");
db.execSQL("create table " + TABLE_LOCALDOWNLOAD_INFO + "(" + "id integer PRIMARY KEY AUTOINCREMENT," + "name varchar(50)," +
"url varchar(100)," + "completedSize integer," + "fileSize integer," + "status integer)");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
/* ， ， ， onUpgrade
* onUpgrade ， 。
* */
String sql = "drop table if exists " + TABLE_DOWNLOAD_INFO + "";
String sqlOne = "drop table if exists " + TABLE_LOCALDOWNLOAD_INFO + "";
db.execSQL(sql);
db.execSQL(sqlOne);
onCreate(db);// ， 。 ，
}
}
/**
* Created by ShanCanCan on 2017/3/6 0006.
*/
public class Dao {
/*
* DAO ， 。
* DAO ， DAO ，
* ， ， ， ， 。
* DAO 。
* */
private static Dao dao;
private static DownLoadDBHelper dbHelper;
public static final byte[] Lock = new byte[0]; //
public static final byte[] file_Lock = new byte[0];
public Dao() {// ，
}
public static synchronized Dao getInstance(Context context) {// demo +
if (dao == null) {
dao = new Dao();
dbHelper = new DownLoadDBHelper(context);
}
return dao;
}
/* public static synchronized Dao getInstance(Context context) {// demo + ，99%
if (dao == null) { //
dao = new Dao();
dbHelper = new DownLoadDBHelper(context);
}
return dao;
}*/
/*************************************** Dao 、 、 、 *********************************************************/
/**
* ，
*
* @param url
* @return
*/
public boolean isExist(String url) {
SQLiteDatabase database = dbHelper.getReadableDatabase(); // app
String sql = "select count(*) from " + TABLE_LOCALDOWNLOAD_INFO + " where url=?"; // ,
Cursor cursor = database.rawQuery(sql, new String[]{url});
/**
*
* @Cursor
* Cursor 。
* moveToFirst() 。
* 。
* 。
* Cursor 。
* 。
* Cursor ，
* ：close(),moveToFirst(),moveToNext(),moveToLast(),moveToPrevious(),getColumnCount() 。
*
* @rawQuery
* rawQuery SQL ， ，
* “？” String[]
* cursor ，cursor ，cursor 。 ！！！
*
* */
cursor.moveToFirst();
int count = cursor.getInt(0);
cursor.close();
return count > 0;
}
/**
*
*
* @param url
* @return
*/
public boolean isFirstDownload(String url) {
SQLiteDatabase database = dbHelper.getReadableDatabase();
String sql = "select count(*) from " + TABLE_DOWNLOAD_INFO + " where url=?";
Cursor cursor = database.rawQuery(sql, new String[]{url});
cursor.moveToFirst();
int count = cursor.getInt(0);
cursor.close();
return count == 0;
}
/**
* list
*
* @param infos
* @param context
*/
public void saveInfos(List<DownLoadInfo> infos, Context context) {
/**
* （Transaction） ， 。
* ， ， 。
* ，SQL Server ，
* 。
*
* ： （ Atomicity ）、 （ Consistency ）、
* （ Isolation ） （ Durability ）。 ACID 。
*
* */
synchronized (Lock) {
SQLiteDatabase database = dbHelper.getWritableDatabase();
database.beginTransaction();//
try {// ，
for (DownLoadInfo info : infos) {//for
String sql = "insert into " + TABLE_DOWNLOAD_INFO + "(thread_id,start_position, end_position, completed_size, url) values (?,?,?,?,?)";
Object[] bindArgs = {info.getThreadId(), info.getStartPosition(), info.getEndPosition(), info.getCompletedSize(), info.getUrl()};
database.execSQL(sql, bindArgs);
}
database.setTransactionSuccessful();//
} catch (SQLException e) {
e.printStackTrace();
} finally {
database.endTransaction();//
}
}
}
/**
*
*
* @param urlstr
* @return List<DownloadInfo> ,
*/
public List<DownLoadInfo> getInfos(String urlstr) {
List<DownLoadInfo> list = new ArrayList<DownLoadInfo>();
SQLiteDatabase database = dbHelper.getReadableDatabase();
String sql = "select thread_id, start_position, end_position, completed_size, url from " + TABLE_DOWNLOAD_INFO + " where url=?";
Cursor cursor = database.rawQuery(sql, new String[]{urlstr});
while (cursor.moveToNext()) {// cursor ， ，
DownLoadInfo info = new DownLoadInfo(cursor.getInt(0), cursor.getInt(1), cursor.getInt(2), cursor.getInt(3), cursor.getString(4));
list.add(info);
}
cursor.close();
return list;
}
/**
* , ，
*
* @param fileStatus
**/
public void insertFileStatus(FileStatus fileStatus) {
synchronized (file_Lock) {// ，
SQLiteDatabase database = dbHelper.getWritableDatabase();
database.beginTransaction();
try {
String sql = "insert into " + TABLE_LOCALDOWNLOAD_INFO + " (name,url,completedSize,fileSize,status) values(?,?,?,?,?)";
Object[] bindArgs = {fileStatus.getName(), fileStatus.getUrl(), fileStatus.getCompletedSize(), fileStatus.getFileSize(), fileStatus.getStatus()};
database.execSQL(sql, bindArgs);
database.setTransactionSuccessful();
} catch (SQLException e) {
e.printStackTrace();
} finally {
database.endTransaction();
}
}
}
/**
* @param context
* @param compeletedSize
* @param threadId
* @param urlstr ，
*/
public void updataInfos(int threadId, int compeletedSize, String urlstr, Context context) {
synchronized (Lock) {
String sql = "update " + TABLE_DOWNLOAD_INFO + "set completed_size = ? where thread_id =? and url=?";
String localSql = "update " + TABLE_LOCALDOWNLOAD_INFO + "set completedSize = (select sum(completed_size) from " +
TABLE_DOWNLOAD_INFO + "where url=? group by url ) where url=?";
Object[] bindArgs = {compeletedSize, threadId, urlstr};
Object[] localArgs = {urlstr, urlstr};
SQLiteDatabase database = dbHelper.getWritableDatabase();
database.beginTransaction();
try {
database.execSQL(sql, bindArgs);
database.execSQL(localSql, localArgs);
database.setTransactionSuccessful();
} catch (SQLException e) {
e.printStackTrace();
} finally {
database.endTransaction();
}
}
}
/**
* @param url ，0 ，1 ,2
**/
public void updateFileStatus(String url) {
synchronized (file_Lock) {
String sql = "update " + TABLE_LOCALDOWNLOAD_INFO + " set status = ? where url = ?";
Object[] bindArgs = {1, url};
SQLiteDatabase database = dbHelper.getWritableDatabase();
database.beginTransaction();
try {
database.execSQL(sql, bindArgs);
database.setTransactionSuccessful();
} catch (SQLException e) {
e.printStackTrace();
} finally {
database.endTransaction();
}
}
}
/**
* @return List<FileStatus>
* ， ，
**/
public List<FileStatus> getFileStatus() {
List<FileStatus> list = new ArrayList<FileStatus>();
SQLiteDatabase database = dbHelper.getReadableDatabase();
//String sql = "slect * from " + TABLE_LOCALDOWNLOAD_INFO + ""; // ，
String sql = "select name, url, status, completedSize, fileSize from " + TABLE_LOCALDOWNLOAD_INFO + "";
Cursor cursor = database.rawQuery(sql, null);
while (cursor.moveToNext()) {
FileStatus fileState = new FileStatus(cursor.getString(0), cursor.getString(1), cursor.getInt(2), cursor.getInt(3), cursor.getInt(4));
list.add(fileState);
}
cursor.close();
return list;
}
/**
* @param url
* @param completeSize
* @param status
**/
public void updateFileDownStatus(int completeSize, int status, String url) {
synchronized (file_Lock) {
String sql = "update " + TABLE_LOCALDOWNLOAD_INFO + " set completedSize = ?,status = ? where url = ?";
SQLiteDatabase database = dbHelper.getWritableDatabase();
database.beginTransaction();
try {
Object[] bindArgs = {completeSize, status, url};
database.execSQL(sql, bindArgs);
database.delete(TABLE_DOWNLOAD_INFO, "url = ?", new String[]{url});
database.setTransactionSuccessful();
} catch (SQLException e) {
e.printStackTrace();
} finally {
database.endTransaction();
}
}
}
/**
* @param url
**/
public String getFileName(String url) {
String result = "";
String sql = "select name from " + TABLE_LOCALDOWNLOAD_INFO + " where url = ?";
SQLiteDatabase database = dbHelper.getReadableDatabase();
Cursor cursor = database.rawQuery(sql, new String[]{url});
if (cursor.moveToNext()) {
result = cursor.getString(0);
}
cursor.close();
return result;
}
/**
* ， ，
*
*
* @param url
*/
public void deleteFile(String url) {
SQLiteDatabase database = dbHelper.getWritableDatabase();
database.beginTransaction();
try {
database.delete(TABLE_DOWNLOAD_INFO, " url = ?", new String[]{url});
database.delete(TABLE_LOCALDOWNLOAD_INFO, " url = ?", new String[]{url});
database.setTransactionSuccessful();
} catch (Exception e) {
e.printStackTrace();
} finally {
database.endTransaction();
}
}
/**
*
*
* @close
*/
public void closeDB() {
dbHelper.close();
}
}
@SuppressLint("HandlerLeak")
public class DownloadService extends Service
{
public IBinder binder = new MyBinder();
public class MyBinder extends Binder
{
public DownloadService getService()
{
return DownloadService.this;
}
}
@Override
public IBinder onBind(Intent intent)
{
return binder;
}
public static int number = 0;
//
public final String savePath = "/mnt/sdcard/MultiFileDownload/";
//
public static List<FileStatus> list = new ArrayList<FileStatus>();
public static Map<String, String> localDownList = new HashMap<String, String>();
//
public static Map<String, Downloader> downloaders = new HashMap<String, Downloader>();
//
private Map<String, Integer> completeSizes = new HashMap<String, Integer>();
//
private Map<String, Integer> fileSizes = new HashMap<String, Integer>();
private Downloader downloader;
private int threadCount = 5;
private Dao dao;
private DownLoadCallback loadCallback;
private FileStatus mFileStatus = null;
private Handler handler = new Handler()
{
@Override
public void handleMessage(Message msg)
{
super.handleMessage(msg);
if (msg.what == 1)
{
String url = (String) msg.obj;
int length = msg.arg1;
int completeSize = completeSizes.get(url);
int fileSize = fileSizes.get(url);
completeSize += length;
completeSizes.put(url, completeSize);
synchronized (list)
{
for (int i = 0; i < list.size(); i++)
{
FileStatus fileStatus = list.get(i);
if (fileStatus.getUrl().equals(url))
{
if (completeSize == fileStatus.getFileSize())
{
System.out.println("----------- :"+fileStatus.getName()+":"+completeSize+"-----"+fileStatus.getFileSize());
list.set(i, new FileStatus(fileStatus.getName(), fileStatus.getUrl(), 1, completeSize, fileStatus.getFileSize()));
dao.updateFileDownStatus(completeSize, 1, url);
}
else
{
list.set(i, new FileStatus(fileStatus.getName(), fileStatus.getUrl(), 0, completeSize, fileStatus.getFileSize()));
}
mFileStatus = list.get(i);
}
}
this.postDelayed(new Runnable()
{
@Override
public void run()
{
if (loadCallback != null && mFileStatus != null)
{
loadCallback.refreshUI(mFileStatus);
}
}
}, 1000);
}
}
}
};
@Override
public void onCreate()
{
super.onCreate();
dao = Dao.getInstance(this);
list = dao.getFileStatus();
for (FileStatus fileStatus : list)
{
localDownList.put(fileStatus.getUrl(), fileStatus.getUrl());
}
Timer timer = new Timer();
timer.schedule(new TimerTask()
{
@Override
public void run()
{
number++;
}
}, 0, 1000);
}
public void download(final Button button, final String url, final String name, final Handler mHandler)
{
if (dao.isExist(url))
{
Toast.makeText(this, " ， ", Toast.LENGTH_SHORT).show();
return;
}
final String fileName = name + url.substring(url.lastIndexOf("."));
new Thread(new Runnable()
{
@Override
public void run()
{
downloader = downloaders.get(url);
if (downloader == null)
{
downloader = new Downloader(url, savePath, fileName, threadCount, DownloadService.this, handler);
downloaders.put(url, downloader);
}
if (downloader.isDownloading())
return;
LoadInfo loadInfo = downloader.getDownloaderInfors();
if(loadInfo != null)
{
FileStatus fileStatus = new FileStatus(fileName, url, 0, loadInfo.getComplete(), loadInfo.getFileSize());
dao.insertFileStatus(fileStatus);
completeSizes.put(url, loadInfo.getComplete());
fileSizes.put(url, fileStatus.getFileSize());
list.add(fileStatus);
localDownList.put(url, url);
downloader.download();
Message msg = new Message();
msg.what = 1;
msg.obj = button;
mHandler.sendMessage(msg);
}
else
{
Message msg = new Message();
msg.what = 2;
msg.obj = button;
mHandler.sendMessage(msg);
}
}
}).start();
}
//
public void Pause(Downloader downloader)
{
downloader.pause();
}
//
public void reDownload(final Button button, final String url, final String name, final Handler mHandler)
{
new Thread(new Runnable()
{
@Override
public void run()
{
String fileName = dao.getFileName(url);
downloader = downloaders.get(url);
if (downloader == null)
{
downloader = new Downloader(url, savePath, fileName, threadCount, DownloadService.this, handler);
downloaders.put(url, downloader);
}
if (downloader.isDownloading())
return;
LoadInfo loadInfo = downloader.getDownloaderInfors();
if(loadInfo != null && !fileName.equals(""))
{
if(!completeSizes.containsKey(url))
{
completeSizes.put(url, loadInfo.getComplete());
}
if(!fileSizes.containsKey(url))
{
fileSizes.put(url, loadInfo.getFileSize());
}
downloader.download();
Message msg = new Message();
msg.what = 1;
msg.obj = button;
mHandler.sendMessage(msg);
}
else
{
Message msg = new Message();
msg.what = 2;
msg.obj = button;
mHandler.sendMessage(msg);
}
}
}).start();
}
public void delete(final String url)
{
Downloader down = downloaders.get(url);
if(down != null)
{
down.pause();
}
handler.postDelayed(new Runnable()
{
@Override
public void run()
{
dao.deleteFile(url);
for (int i = 0; i < list.size(); i++)
{
FileStatus fileStatus = list.get(i);
if (fileStatus.getUrl().equals(url))
{
list.remove(i);
}
}
localDownList.remove(url);
downloaders.remove(url);
completeSizes.remove(url);
fileSizes.remove(url);
if(loadCallback != null)
{
loadCallback.deleteFile(url);
}
}
}, 1000);
}
public interface DownLoadCallback
{
public void refreshUI(FileStatus fileStatus);
public void deleteFile(String url);
}
public void setLoadCallback(DownLoadCallback loadCallback)
{
this.loadCallback = loadCallback;
}
}
/**
* Created by ShanCanCan on 2017/3/7 0007.
*/
public class DownLoadUtil {
/**
*
* 1、
* 2、 , httpurlconnection
*/
private String downPath;//
private String savePath;//
private String fileName;//
private int threadCount;//
private Handler mHandler;
private Dao dao;
private Context context;
private int fileSize;//
private int range;
private List<DownLoadInfo> infos;//
private int state = INIT;
private static final int INIT = 1;// ： ， ，
private static final int DOWNLOADING = 2;
private static final int PAUSE = 3;
/**
* ， dao
*
* @param downPath
* @param savePath
* @param fileName
* @param threadCount
* @param context
* @param mHandler
*/
public DownLoadUtil(String downPath, String savePath, String fileName, int threadCount, Handler mHandler, Context context) {
this.downPath = downPath;
this.savePath = savePath;
this.fileName = fileName;
this.threadCount = threadCount;
this.mHandler = mHandler;
this.context = context;
dao = Dao.getInstance(context);
}
/**
* PAUSE
**/
public boolean isPause() {
return state == PAUSE;
}
/**
* DOWNLOADING
*/
public boolean isDownloading() {
return state == DOWNLOADING;
}
/**
* @param url ， dao
*/
private boolean isFirst(String url) {
return dao.isFirstDownload(url);
}
/**
*
*/
public LoadItemInfo getDownloadInfos() {
if (isFirst(downPath)) {
if (initFirst()) {// ， ,1. 2. ,
range = this.fileSize / this.threadCount;
infos = new ArrayList<DownLoadInfo>();
// ， ？ RandomAccessFile。 DownLoadInfo RandomAccessFile
for (int i = 0; i < this.threadCount - 1; i++) {
DownLoadInfo info = new DownLoadInfo(i, i * range, (i + 1) * range - 1, 0, downPath);
infos.add(info);
}
DownLoadInfo info = new DownLoadInfo(this.threadCount - 1, (this.threadCount - 1) * range, this.fileSize, 0, downPath);
infos.add(info);
dao.saveInfos(infos, this.context);
//(String urlDownload, int completePercent, int fileSize)
LoadItemInfo loadInfo = new LoadItemInfo(this.downPath, 0, this.fileSize);
return loadInfo;
} else {
return null;
}
} else {
// ， ？
infos = dao.getInfos(this.downPath);
if (infos != null && infos.size() > 0) {
int size = 0;
int completeSize = 0;
for (DownLoadInfo info : infos) {
completeSize += info.getCompletedSize();
size += info.getEndPosition() - info.getStartPosition() + this.threadCount - 1;
}
LoadItemInfo loadInfo = new LoadItemInfo(this.downPath, completeSize, size);
return loadInfo;
} else {
return null;
}
}
}
//
public void pause() {
state = PAUSE;
}
// , init
public void reset() {
state = INIT;
}
/**
* ，RandomAccessFile ， DataInputStream DataOutputStream ， ，
* getFilePointer( )， seek( )， length( )、skipBytes() 。
* ， ("r")， ("rw") ( C fopen( ) )。 。
*/
private boolean initFirst() {
boolean result = true;
HttpURLConnection conn = null;
RandomAccessFile randomFile = null;
URL url = null;
try {
url = new URL(downPath);
conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(5 * 1000);
conn.setRequestMethod("GET");
// http 200 206
if (conn.getResponseCode() == 200 || conn.getResponseCode() == 206) // (206)， GET
{
fileSize = conn.getContentLength();//
if (fileSize <= 0) {
//(" , ");
return false;
}
File dir = new File(savePath);
// ,
if (!dir.exists()) {
if (dir.mkdirs()) {
//("mkdirs success.");
}
}
File file = new File(this.savePath, this.fileName);
randomFile = new RandomAccessFile(file, "rwd");
randomFile.setLength(fileSize);//
randomFile.close();
conn.disconnect();
}
} catch (Exception e) {
e.printStackTrace();
result = false;
} finally {
if (randomFile != null) {
try {
randomFile.close();
} catch (IOException e) {
e.printStackTrace();
}
}
if (conn != null) {
conn.disconnect();
}
}
return result;
}
/**
*
*/
public void downLoad() {
if (infos != null) {
if (state == DOWNLOADING) {
return;
}
state = DOWNLOADING;//
for (DownLoadInfo info : infos) {// ？ RandomAccessFile
new DownLoadThread(info.getThreadId(), info.getStartPosition(), info.getEndPosition(), info.getCompletedSize(), info.getUrl(), this.context).start();
}
}
}
/**
* ，
*/
public class DownLoadThread extends Thread {
private int threadId;
private int startPostion;
private int endPostion;
private int compeletedSize;
private String url;
private Context context;
public static final int PROGRESS = 1;
public DownLoadThread(int threadId, int startPostion, int endPostion, int compeletedSize, String url, Context context) {// ，
this.threadId = threadId;
this.startPostion = startPostion;
this.endPostion = endPostion;
this.compeletedSize = compeletedSize;
this.url = url;
this.context = context;
}
//
@Override
public void run() {
HttpURLConnection conn = null;
RandomAccessFile randomAccessFile = null;
InputStream inStream = null;
File file = new File(savePath, fileName);
URL url = null;
try {
url = new URL(this.url);
conn = (HttpURLConnection) url.openConnection();
constructConnection(conn);
if (conn.getResponseCode() == 200 || conn.getResponseCode() == 206) {
randomAccessFile = new RandomAccessFile(file, "rwd");
randomAccessFile.seek(this.startPostion + this.compeletedSize);//RandomAccessFile ，
inStream = conn.getInputStream();
byte buffer[] = new byte[4096];// 4096 ？ ， apk 4096，
int length = 0;
while ((length = inStream.read(buffer, 0, buffer.length)) != -1) {
randomAccessFile.write(buffer, 0, length);
compeletedSize += length;
//
dao.updataInfos(threadId, compeletedSize, this.url, this.context);
// ，
Message message = Message.obtain();
message.what = PROGRESS;
message.obj = this.url;
message.arg1 = length;
mHandler.sendMessage(message);// DownloadService
if (state == PAUSE) {
//("-----pause-----");
return;
}
}
// ("------------ :" + this.threadId + " ");
}
} catch (IOException e) {
e.printStackTrace();
//("----- -----"); ，
} finally {// ， ，
try {
if (inStream != null) {
inStream.close();
}
if (randomAccessFile != null) {
randomAccessFile.close();
}
if (conn != null) {
conn.disconnect();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
*
*
* @param conn
*/
private void constructConnection(HttpURLConnection conn) throws IOException {
conn.setConnectTimeout(5 * 1000);// 5
conn.setRequestMethod("GET");// GET ， post conn.setDoOutput(true); conn.setDoInput(true);
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", this.url);
conn.setRequestProperty("Charset", "UTF-8");
int startPositionNew = this.startPostion + this.compeletedSize;
//
conn.setRequestProperty("Range", "bytes=" + startPositionNew + "-" + this.endPostion);
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();
}
}
}
이상 이 바로 본 고의 모든 내용 입 니 다.여러분 의 학습 에 도움 이 되 고 저 희 를 많이 응원 해 주 셨 으 면 좋 겠 습 니 다.
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