안드로이드 갤러리에 있는 JPG 이미지 파일을 PC의 자바 서버 프로그램으로 전송하는 예제입니다.
최근들어 관련 질문이 많아져서 만들어봤습니다. 참고하세요.
기존 포스팅의 코드를 수정해서 사용해야 합니다. 우선 다음 포스팅을 해본 후 이번 포스팅을 이어서 진행하세요.
최초 작성 - 2018. 9. 13
실행 결과
1. 자바 서버 프로그램을 먼저 실행해둡니다.
[Thu Sep 13 13:01:05 KST 2018] Local Bluetooth device...
BlueCove version 2.1.1-SNAPSHOT on winsock
[Thu Sep 13 13:01:06 KST 2018] address: F8633F2710E0
[Thu Sep 13 13:01:06 KST 2018] name: WEBNAUTES-PC
[Thu Sep 13 13:01:06 KST 2018] Opened connection successful.
[Thu Sep 13 13:01:06 KST 2018] Server is now running.
[Thu Sep 13 13:01:06 KST 2018] wait for client requests... |
2. 안드로이드 앱에서 연결합니다.
3. IMAGE 버튼을 선택합니다.
4. 갤러리에서 전송할 이미지를 선택합니다.
5. 전송이 완료되었습니다.
6. 서버에서도 전송결과를 확인할 수 있습니다.
[Thu Sep 13 13:02:07 KST 2018] Me : 에코 서버에 접속하셨습니다.
[Thu Sep 13 13:02:07 KST 2018] Me : 보내신 문자를 에코해드립니다.
[Thu Sep 13 13:02:07 KST 2018] ready
[Thu Sep 13 13:02:21 KST 2018] D013FDEE432E: [Start28874]
[Thu Sep 13 13:02:21 KST 2018] start recv image 28874
read 1011/28874 bytes.
read 2022/28874 bytes.
read 3033/28874 bytes.
read 4096/28874 bytes.
read 5107/28874 bytes.
read 6118/28874 bytes.
read 7129/28874 bytes.
read 8140/28874 bytes.
read 9151/28874 bytes.
read 10162/28874 bytes.
read 11173/28874 bytes.
read 12184/28874 bytes.
read 13195/28874 bytes.
read 14206/28874 bytes.
read 15217/28874 bytes.
read 16228/28874 bytes.
read 17239/28874 bytes.
read 18250/28874 bytes.
read 19261/28874 bytes.
read 20272/28874 bytes.
read 21283/28874 bytes.
read 22294/28874 bytes.
read 23305/28874 bytes.
read 24316/28874 bytes.
read 25327/28874 bytes.
read 26338/28874 bytes.
read 27349/28874 bytes.
read 28360/28874 bytes.
read 28874/28874 bytes.
[Thu Sep 13 13:02:21 KST 2018] end
[Thu Sep 13 13:02:21 KST 2018] Me : recv Image
[Thu Sep 13 13:02:21 KST 2018] ready |
7. 서버 프로그램 폴더에서 전송받은 이미지를 확인할 수 있습니다.
안드로이드 코드 수정
갤러리에서 이미지 파일을 가져오는 코드와 런타임 퍼미션 코드를 추가합니다.
1. 메니페스트 파일에 다음 권한을 추가합니다.
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> |
2. build.gradle에 com.android.support:design를 추가합니다. 퍼미션 관련 코드에서 Snackbar를 사용하기 위해 필요합니다.
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'com.android.support:appcompat-v7:27.1.1'
implementation 'com.android.support.constraint:constraint-layout:1.1.2'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
implementation 'com.android.support:design:27.1.1'
} |
3. 레이아웃 파일 activity_main.xml에 이미지 전송을 위한 버튼을 추가합니다. Snackbar를 사용하기 위해 레이아웃에 id도 추가해야 합니다.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:paddingBottom="10dp"
android:paddingTop="10dp"
android:id="@+id/layout_main"
android:layout_width="match_parent"
android:layout_height="match_parent">
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
<LinearLayout
android:weightSum="1"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<EditText
android:id="@+id/input_string_edittext"
android:hint="input text here"
android:layout_weight="0.6"
android:layout_width="0dp"
android:layout_height="wrap_content"/>
<Button
android:id="@+id/send_button"
android:layout_weight="0.2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Send" />
<Button
android:id="@+id/send_image_button"
android:layout_weight="0.2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="Image" />
</LinearLayout>
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
4. MainActivity.java 파일에 갤러리로부터 파일을 가져와 전송하는 코드를 추가합니다.
public class MainActivity extends AppCompatActivity
implements ActivityCompat.OnRequestPermissionsResultCallback {
private final int REQUEST_BLUETOOTH_ENABLE = 100;
private final int GET_GALLERY_IMAGE = 200;
private View mLayout; // Snackbar 사용하기 위해서는 View가 필요합니다.
private TextView mConnectionStatus;
|
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mLayout = findViewById(R.id.layout_main); |
Button sendButton = (Button)findViewById(R.id.send_button);
sendButton.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
String sendMessage = mInputEditText.getText().toString();
if ( sendMessage.length() > 0 ) {
sendMessage(sendMessage);
}
}
});
Button sendImageButton = (Button)findViewById(R.id.send_image_button);
sendImageButton.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
Intent intent = new Intent(Intent.ACTION_PICK);
intent.setData(android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
intent.setType("image/*");
startActivityForResult(intent, GET_GALLERY_IMAGE);
}
});
mConnectionStatus = (TextView)findViewById(R.id.connection_status_textview); |
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if(requestCode == REQUEST_BLUETOOTH_ENABLE){
if (resultCode == RESULT_OK){
//BlueTooth is now Enabled
showPairedDevicesListDialog();
}
if(resultCode == RESULT_CANCELED){
showQuitDialog( "You need to enable bluetooth");
}
}else if ( requestCode == GET_GALLERY_IMAGE){
sendPicture(data.getData()); }
}
private void sendPicture(Uri imgUri) {
String imagePath = getRealPathFromURI(imgUri); Log.e(TAG, imagePath);
File file = new File(imagePath);
sendMessage("Start"+file.length());
try
{
FileInputStream fis = new FileInputStream(imagePath);
byte[] buffer = new byte[4096];
int totalSize = fis.available();
int readSize = 0;
while ( (readSize=fis.read(buffer)) > 0) {
mConnectedTask.mOutputStream.write(buffer, 0, readSize);
}
fis.close();
;
}
catch (Exception e)
{
e.printStackTrace();
}
mConversationArrayAdapter.insert("Me: " + "Send Image" , 0);
}
private String getRealPathFromURI(Uri contentUri) {
String[] proj = {MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(contentUri, proj, null, null, null);
cursor.moveToFirst();
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
return cursor.getString(column_index);
} |
5. 안드로이드 6.0 이상의 경우 이미지에 접근하기 위해 런타임 퍼미션도 필요합니다. 코드 설명은 다음 포스팅을 참고하세요.
Button sendImageButton = (Button)findViewById(R.id.send_image_button);
sendImageButton.setOnClickListener(new View.OnClickListener(){
public void onClick(View v){
Intent intent = new Intent(Intent.ACTION_PICK);
intent.setData(android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
intent.setType("image/*");
startActivityForResult(intent, GET_GALLERY_IMAGE);
}
});
int writeExternalStoragePermission = ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE);
if ( writeExternalStoragePermission != PackageManager.PERMISSION_GRANTED){
if (ActivityCompat.shouldShowRequestPermissionRationale(this, REQUIRED_PERMISSIONS[0])) {
Snackbar.make(mLayout, "이 앱을 실행하려면 카메라와 외부 저장소 접근 권한이 필요합니다.",
Snackbar.LENGTH_INDEFINITE).setAction("확인", new View.OnClickListener() {
@Override
public void onClick(View view) {
ActivityCompat.requestPermissions( MainActivity.this, REQUIRED_PERMISSIONS,
PERMISSIONS_REQUEST_CODE);
}
}).show();
} else {
ActivityCompat.requestPermissions( this, REQUIRED_PERMISSIONS,
PERMISSIONS_REQUEST_CODE);
}
}
mConnectionStatus = (TextView)findViewById(R.id.connection_status_textview); |
else { Log.d(TAG, "Initialisation successful.");
showPairedDevicesListDialog(); } }
private static final int PERMISSIONS_REQUEST_CODE = 100;
String[] REQUIRED_PERMISSIONS = {Manifest.permission.WRITE_EXTERNAL_STORAGE};
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grandResults) {
if ( requestCode == PERMISSIONS_REQUEST_CODE && grandResults.length == REQUIRED_PERMISSIONS.length) {
boolean check_result = true;
for (int result : grandResults) {
if (result != PackageManager.PERMISSION_GRANTED) {
check_result = false;
break;
}
}
if ( check_result ) {
;
}
else {
if (ActivityCompat.shouldShowRequestPermissionRationale(this, REQUIRED_PERMISSIONS[0])) {
Snackbar.make(mLayout, "퍼미션이 거부되었습니다. 앱을 다시 실행하여 퍼미션을 허용해주세요. ",
Snackbar.LENGTH_INDEFINITE).setAction("확인", new View.OnClickListener() {
@Override
public void onClick(View view) {
finish();
}
}).show();
}else {
Snackbar.make(mLayout, "퍼미션이 거부되었습니다. 설정(앱 정보)에서 퍼미션을 허용해야 합니다. ",
Snackbar.LENGTH_INDEFINITE).setAction("확인", new View.OnClickListener() {
@Override
public void onClick(View view) {
finish();
}
}).show();
}
}
}
}
@Override
protected void onDestroy() { |
자바 전체 코드
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.DataInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Reader;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.Date;
import javax.bluetooth.BluetoothStateException;
import javax.bluetooth.LocalDevice;
import javax.bluetooth.RemoteDevice;
import javax.bluetooth.UUID;
import javax.microedition.io.Connector;
import javax.microedition.io.StreamConnection;
import javax.microedition.io.StreamConnectionNotifier;
public class Server{
public static void main(String[] args){
log("Local Bluetooth device...\n");
LocalDevice local = null;
try {
local = LocalDevice.getLocalDevice();
} catch (BluetoothStateException e2) {
}
log( "address: " + local.getBluetoothAddress() );
log( "name: " + local.getFriendlyName() );
Runnable r = new ServerRunable();
Thread thread = new Thread(r);
thread.start();
}
private static void log(String msg) {
System.out.println("["+(new Date()) + "] " + msg);
}
}
class ServerRunable implements Runnable{
//UUID for SPP
final UUID uuid = new UUID("0000110100001000800000805F9B34FB", false);
final String CONNECTION_URL_FOR_SPP = "btspp://localhost:"
+ uuid +";name=SPP Server";
private StreamConnectionNotifier mStreamConnectionNotifier = null;
private StreamConnection mStreamConnection = null;
private int count = 0;
private boolean recvImage = false;
@Override
public void run() {
try {
mStreamConnectionNotifier = (StreamConnectionNotifier) Connector
.open(CONNECTION_URL_FOR_SPP);
log("Opened connection successful.");
} catch (IOException e) {
log("Could not open connection: " + e.getMessage());
return;
}
log("Server is now running.");
while(true){
log("wait for client requests...");
try {
mStreamConnection = mStreamConnectionNotifier.acceptAndOpen();
} catch (IOException e1) {
log("Could not open connection: " + e1.getMessage() );
}
count++;
log("현재 접속 중인 클라이언트 수: " + count);
new Receiver(mStreamConnection).start();
}
}
class Receiver extends Thread {
private InputStream mInputStream = null;
private OutputStream mOutputStream = null;
private String mRemoteDeviceString = null;
private StreamConnection mStreamConnection = null;
Receiver(StreamConnection streamConnection){
mStreamConnection = streamConnection;
try {
mInputStream = mStreamConnection.openInputStream();
mOutputStream = mStreamConnection.openOutputStream();
log("Open streams...");
} catch (IOException e) {
log("Couldn't open Stream: " + e.getMessage());
Thread.currentThread().interrupt();
return;
}
try {
RemoteDevice remoteDevice
= RemoteDevice.getRemoteDevice(mStreamConnection);
mRemoteDeviceString = remoteDevice.getBluetoothAddress();
log("Remote device");
log("address: "+ mRemoteDeviceString);
} catch (IOException e1) {
log("Found device, but couldn't connect to it: " + e1.getMessage());
return;
}
log("Client is connected...");
}
@Override
public void run() {
try {
Reader mReader = new BufferedReader(new InputStreamReader
( mInputStream, Charset.forName(StandardCharsets.UTF_8.name())));
boolean isDisconnected = false;
StringBuilder imageStringBuilder = null;
Sender("에코 서버에 접속하셨습니다.");
Sender( "보내신 문자를 에코해드립니다.");
while(true){
log("ready");
StringBuilder stringBuilder = new StringBuilder();
int c = 0;
while ( '\n' != (char)( c = mReader.read()) ) {
if ( c == -1){
log("Client has been disconnected");
count--;
log("현재 접속 중인 클라이언트 수: " + count);
isDisconnected = true;
Thread.currentThread().interrupt();
break;
}
stringBuilder.append((char) c);
}
if ( isDisconnected ) break;
String recvMessage = stringBuilder.toString();
log( mRemoteDeviceString + ": [" + recvMessage +"]" );
if (recvMessage.matches("Start.*")) {
recvImage = true;
log("start recv image "+ recvMessage.substring(5));
int size = Integer.parseInt(recvMessage.substring(5));
DataInputStream dis = new DataInputStream(mInputStream);
FileOutputStream fos = new FileOutputStream("testfile.jpg");
byte[] buffer = new byte[4096];
int read = 0;
int totalRead = 0;
while((read = dis.read(buffer)) > 0) {
totalRead += read;
System.out.println("read " + totalRead + "/" + size + " bytes.");
fos.write(buffer, 0, read);
if ( totalRead >= size) break;
}
log("end");
fos.flush();
fos.close();
recvImage = false;
recvMessage = "recv Image";
}
if (recvImage == false )
Sender(recvMessage);
}
} catch (IOException e) {
log("Receiver closed" + e.getMessage());
}
}
void Sender(String msg){
PrintWriter printWriter = new PrintWriter(new BufferedWriter
(new OutputStreamWriter(mOutputStream,
Charset.forName(StandardCharsets.UTF_8.name()))));
printWriter.write(msg+"\n");
printWriter.flush();
log( "Me : " + msg );
}
}
private static void log(String msg) {
System.out.println("["+(new Date()) + "] " + msg);
}
}
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