Splitting implementation into 2 methods

dfu/src/main/java/no/nordicsemi/android/dfu/SecureDfuImpl.java

@@ -207,17 +207,75 @@ import no.nordicsemi.android.error.SecureDfuError;
 		// End
 
 		try {
+			sendInitPacket(gatt);
+			sendFirmware(gatt);
+
+			// The device will reset so we don't have to send Disconnect signal.
+			mProgressInfo.setProgress(DfuBaseService.PROGRESS_DISCONNECTING);
+			mService.waitUntilDisconnected();
+			mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_INFO, "Disconnected by the remote device");
+
+			// We are ready with DFU, the device is disconnected, let's close it and finalize the operation.
+			finalize(intent, false);
+		} catch (final UnknownResponseException e) {
+			final int error = DfuBaseService.ERROR_INVALID_RESPONSE;
+			loge(e.getMessage());
+			mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_ERROR, e.getMessage());
+			mService.terminateConnection(gatt, error);
+		} catch (final RemoteDfuException e) {
+			final int error = DfuBaseService.ERROR_REMOTE_MASK | e.getErrorNumber();
+			loge(e.getMessage());
+			mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_ERROR, String.format("Remote DFU error: %s", SecureDfuError.parse(error)));
+
+			try {
+				final ErrorMessage details = readLastError();
+				mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_ERROR, "Details: " + details.message + " (Code = " + details.code + ")");
+				logi("Error details: " + details.message + " (Code = " + details.code + ")");
+			} catch (final Exception e1) {
+				loge("Reading error details failed", e1);
+				mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_WARNING, "Reading error details failed");
+			}
+			mService.terminateConnection(gatt, error);
+		}
+	}
+
+	/**
+	 * This method does the following:
+	 * <ol>
+	 *     <li>Reads Command Object Info - this returns the maximum acceptable size of a command object, and the offset and CRC32 of the command
+	 *     that is already stored in the device (in case the DFU was started in a previous connection and disconnected before it has finished).</li>
+	 *     <li>If the offset received is greater than 0 and less or equal to the size of the Init file that is to be sent, it will compare the
+	 *     received CRC with the local one and, if they match:
+	 *     	<ul>
+	 *     	    <li>If offset < init file size - it will continue sending the Init file from the point it stopped before,</li>
+	 *     	    <li>If offset == init file size - it will send the Calculate Checksum request to obtain a CRC of a current object.
+	 *     	    <ul>
+	 *     	    	<li>If the received CRC is the same as above ones, it will send Execute command to execute the Init file, as it may have not been executed before.</li>
+	 *     	    	<li>If the received CRC is different, that means that the Data Object has already been created in the previous connection and this method will return.</li>
+	 *     	    </ul>
+	 *     	    </li>
+	 *     	</ul>
+	 *     </li>
+	 *     <li>If the CRCs don't match, or the received offset is > init file size, it create the Command Object and send the whole Init file as the previous one
+	 *     was different.</li>
+	 * </ol>
+	 * Sending of the Init packet is done without using PRNs (Packet Receipt Notifications), so they are disabled prior to sending the data.
+	 * @param gatt the target GATT device
+	 * @throws RemoteDfuException
+	 * @throws DeviceDisconnectedException
+	 * @throws DfuException
+	 * @throws UploadAbortedException
+	 * @throws UnknownResponseException
+	 */
+	private void sendInitPacket(final BluetoothGatt gatt) throws RemoteDfuException, DeviceDisconnectedException, DfuException, UploadAbortedException, UnknownResponseException {
 		final CRC32 crc32 = new CRC32(); // Used to calculate CRC32 of the Init packet
 		ObjectChecksum checksum;
-			ObjectInfo info;
-			byte[] response;
-			int status;
 
 		// First, read the Command Object Info. This give information about the maximum command size and whether there is already
 		// one saved from a previous connection. It offset and CRC returned are not equal zero, we can compare it with the current init file
 		// and skip sending it for the second time.
 		logi("Sending Read Command Object Info command (Op Code = 6, Type = 1)");
-			info = readObjectInfo(OBJECT_COMMAND);
+		final ObjectInfo info = readObjectInfo(OBJECT_COMMAND);
 		mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION, String.format(Locale.US, "Command object info received (Max size = %d, Offset = %d, CRC = %08X)", info.maxSize, info.offset, info.CRC32));
 		if (mInitPacketSizeInBytes > info.maxSize) {
 			// Ignore this. DFU target will send an error if init packet is too large after sending the 'Create object' command
@@ -227,7 +285,7 @@ import no.nordicsemi.android.error.SecureDfuError;
 		// and resume sending the init packet, or even skip sending it if the whole file was sent before.
 		boolean skipSendingInitPacket = false;
 		boolean resumeSendingInitPacket = false;
-			if (info.offset > 0) {
+		if (info.offset > 0 && info.offset <= mInitPacketSizeInBytes) {
 			try {
 				// Read the same number of bytes from the current init packet to calculate local CRC32
 				final byte[] buffer = new byte[info.offset];
@@ -251,7 +309,7 @@ import no.nordicsemi.android.error.SecureDfuError;
 					}
 				} else {
 					// A different Init packet was sent before, or the error occurred while sending.
-						// We have to send the while Init packet again.
+					// We have to send the whole Init packet again.
 					mInitPacketStream.reset();
 					crc32.reset();
 				}
@@ -352,7 +410,18 @@ import no.nordicsemi.android.error.SecureDfuError;
 				// It looks like we have started sending the Data already, let's continue
 			}
 		}
+	}
 
+	/**
+	 * This method enables
+	 * @param gatt the target GATT device
+	 * @throws RemoteDfuException
+	 * @throws DeviceDisconnectedException
+	 * @throws DfuException
+	 * @throws UploadAbortedException
+	 * @throws UnknownResponseException
+	 */
+	private void sendFirmware(final BluetoothGatt gatt) throws RemoteDfuException, DeviceDisconnectedException, DfuException, UploadAbortedException, UnknownResponseException {
 		// Send the number of packets of firmware before receiving a receipt notification
 		final int numberOfPacketsBeforeNotification = mPacketsBeforeNotification;
 		if (numberOfPacketsBeforeNotification > 0) {
@@ -366,7 +435,7 @@ import no.nordicsemi.android.error.SecureDfuError;
 
 		logi("Sending Read Data Object Info command (Op Code = 6, Type = 2)");
 		mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION, "Reading data object info...");
-			info = readObjectInfo(OBJECT_DATA);
+		final ObjectInfo info = readObjectInfo(OBJECT_DATA);
 		mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION, String.format(Locale.US, "Data object info received (Max size = %d, Offset = %d, CRC = %08X)", info.maxSize, info.offset, info.CRC32));
 		mProgressInfo.setMaxObjectSizeInBytes(info.maxSize);
 
@@ -442,7 +511,7 @@ import no.nordicsemi.android.error.SecureDfuError;
 
 			// Calculate Checksum
 			logi("Sending Calculate Checksum command (Op Code = 3)");
-				checksum = readChecksum();
+			final ObjectChecksum checksum = readChecksum();
 			mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION, String.format(Locale.US, "Checksum received (Offset = %d, CRC = %08X)", checksum.offset, checksum.CRC32));
 			logi(String.format(Locale.US, "Checksum received (Offset = %d, CRC = %08X)", checksum.offset, checksum.CRC32));
 
@@ -481,34 +550,6 @@ import no.nordicsemi.android.error.SecureDfuError;
 		final long endTime = SystemClock.elapsedRealtime();
 		logi("Transfer of " + mProgressInfo.getBytesSent() + " bytes has taken " + (endTime - startTime) + " ms");
 		mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION, "Upload completed in " + (endTime - startTime) + " ms");
-
-			// The device will reset so we don't have to send Disconnect signal.
-			mProgressInfo.setProgress(DfuBaseService.PROGRESS_DISCONNECTING);
-			mService.waitUntilDisconnected();
-			mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_INFO, "Disconnected by the remote device");
-
-			// We are ready with DFU, the device is disconnected, let's close it and finalize the operation.
-			finalize(intent, false);
-		} catch (final UnknownResponseException e) {
-			final int error = DfuBaseService.ERROR_INVALID_RESPONSE;
-			loge(e.getMessage());
-			mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_ERROR, e.getMessage());
-			mService.terminateConnection(gatt, error);
-		} catch (final RemoteDfuException e) {
-			final int error = DfuBaseService.ERROR_REMOTE_MASK | e.getErrorNumber();
-			loge(e.getMessage());
-			mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_ERROR, String.format("Remote DFU error: %s", SecureDfuError.parse(error)));
-
-			try {
-				final ErrorMessage details = readLastError();
-				mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_ERROR, "Details: " + details.message + " (Code = " + details.code + ")");
-				logi("Error details: " + details.message + " (Code = " + details.code + ")");
-			} catch (final Exception e1) {
-				loge("Reading error details failed", e1);
-				mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_WARNING, "Reading error details failed");
-			}
-			mService.terminateConnection(gatt, error);
-		}
 	}
 
 	/**