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nmea $GPRMC support added
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Lukas Vacek committed Mar 6, 2015
1 parent b4a2460 commit ca4d4ec
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Showing 4 changed files with 210 additions and 3 deletions.
8 changes: 8 additions & 0 deletions .idea/inspectionProfiles/Project_Default.xml
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7 changes: 6 additions & 1 deletion app/src/main/java/github/luv/mockgeofix/CommandDispatcher.java
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Original file line number Diff line number Diff line change
Expand Up @@ -50,7 +50,12 @@ protected void _dispatch(SocketChannel client, String command) {
if ( passwordCommand.passwordRequired() && (! passwordCommand.loggedIn(client)) ) {
ResponseWriter.notLoggedIn(client);
} else {
geoCommand.execute(client, command);
try {
geoCommand.execute(client, command);
} catch (Throwable ex) {
// anything goes wrong, just ignore this command
Log.e(TAG, "error during executing geo command: "+ex.toString());
}
}
} else if (cmd.equals("help")) {
helpCommand.execute(client, command);
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11 changes: 10 additions & 1 deletion app/src/main/java/github/luv/mockgeofix/MockLocationProvider.java
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Expand Up @@ -46,12 +46,15 @@ static public void simulate(double longitude, double latitude, double altitude,
getInstance()._simulate(longitude, latitude, altitude, satellites);
}

@SuppressWarnings("UnusedDeclaration")
static public void simulate(Location location) {
getInstance()._verifyInitiated();
getInstance()._simulate(location);
}

static public Location getLocation() {
return new Location(locationProviderName);
}

protected void _init(Context context) {
if (mContext != null) {
throw new AssertionError(TAG+".init called twice!");
Expand Down Expand Up @@ -93,6 +96,12 @@ protected void _simulate(double longitude, double latitude, double altitude, int
}

protected void _simulate(Location location) {
if (!location.hasAccuracy()) {
location.setAccuracy(accuracy);
}
if (!location.hasAltitude()) {
location.setAltitude(0);
}
try {
Method locationJellyBeanFixMethod = Location.class.getMethod("makeComplete");
if (locationJellyBeanFixMethod != null) {
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187 changes: 186 additions & 1 deletion app/src/main/java/github/luv/mockgeofix/command/GeoNmeaCommand.java
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Original file line number Diff line number Diff line change
@@ -1,17 +1,202 @@
package github.luv.mockgeofix.command;

import android.annotation.SuppressLint;
import android.content.Context;
import android.location.Location;
import android.util.Log;

import java.nio.channels.SocketChannel;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;

import github.luv.mockgeofix.MockLocationProvider;
import github.luv.mockgeofix.util.ResponseWriter;

public class GeoNmeaCommand implements Command {
Context mContext;
String TAG = "GeoNmeaCommand";

GeoNmeaCommand(Context context) {
mContext = context;
}

@Override
public void execute(SocketChannel client, String command) {
String[] args = command.split(" ");
String[] nmeaFields;

try {
nmeaFields = args[2].split(",");
} catch (IndexOutOfBoundsException ex) {
ResponseWriter.writeLine(client,
"KO: NMEA sentence missing, try 'help geo nmea'");
return;
}

String type;
try {
type = nmeaFields[0];
} catch (IndexOutOfBoundsException ex) {
// ok because that's what the emulator does as well
ResponseWriter.ok(client);
return;
}

if (type.equals("$GPRMC")) {
processGPRMC(client, nmeaFields, command);
} else if (type.equals("$GPGGA")) {
processGPGGA(client, nmeaFields, command);
} else {
// ok because that's what the emulator does as well
ResponseWriter.ok(client);
}
}

public void processGPRMC(SocketChannel client, String[] nmeaFields, String command) {
// example: $GPRMC,081836,A,3751.65,S,14507.36,E,000.0,360.0,130998,011.3,E*62
/* example fields:
225446 Time of fix 22:54:46 UTC
A Status A=active or V=Void
4916.45,N Latitude 49 deg. 16.45 min North
12311.12,W Longitude 123 deg. 11.12 min West
000.5 Speed over ground, Knots
054.7 Track angle in degrees, True
191194 Date of fix 19 November 1994
020.3,E Magnetic variation 20.3 deg East
optional field: mode indicator
(can be A=autonomous, D=differential, E=Estimated, N=not valid, S=Simulator)
*68 mandatory checksum
*/

String strTime, strStatus, strLatitude, strLatitudeQual, strLongitude, strLongitudeQual,
strSpeed, strTrackAngle, strDate;
try {
strTime = nmeaFields[1];
strStatus = nmeaFields[2];
strLatitude = nmeaFields[3];
strLatitudeQual = nmeaFields[4];
strLongitude = nmeaFields[5];
strLongitudeQual = nmeaFields[6];
strSpeed = nmeaFields[7];
strTrackAngle = nmeaFields[8];
strDate = nmeaFields[9];
} catch (IndexOutOfBoundsException ex) {
// ok because that's what the emulator does as well
Log.i(TAG, "Ignoring Nmea sentence: too few fields: "+command);
ResponseWriter.ok(client);
return;
}

if (!checkChecksum(command)) {
ResponseWriter.ok(client);
Log.i(TAG, "Ignoring Nmea sentence: invalid checksum: "+command);
return;
}

if (strStatus.toLowerCase().equals("v")) {
ResponseWriter.ok(client);
Log.i(TAG, "Ignoring Nmea sentence: Status is 'V' (void): "+command);
return;
}

long timestamp;
double latitude;
double longitude;
float speed;
float bearing;
try {
timestamp = convertTimeAndDate(strTime, strDate);
} catch(ParseException ex) {
ResponseWriter.ok(client);
Log.i(TAG, "Ignoring Nmea sentence: Can't parse date or time: "+command);
return;
}

try {
latitude = convertLatitude(strLatitude, strLatitudeQual);
longitude = convertLongitude(strLongitude, strLongitudeQual);
} catch(NumberFormatException ex) {
ResponseWriter.ok(client);
Log.i(TAG, "Ignoring Nmea sentence: Can't parse latitude or longitude: "+command);
return;
}

try {
speed = Float.valueOf(strSpeed) * (float)0.51444;
} catch(NumberFormatException ex) {
ResponseWriter.ok(client);
Log.i(TAG, "Ignoring Nmea sentence: Can't parse speed: "+command);
return;
}

try {
// this might be completely wrong
bearing = Float.valueOf(strTrackAngle);
} catch(NumberFormatException ex) {
ResponseWriter.ok(client);
Log.i(TAG, "Ignoring Nmea sentence: Can't parse track angle: "+command);
return;
}

Location location = MockLocationProvider.getLocation();
location.setTime(timestamp);
location.setLatitude(latitude);
location.setLongitude(longitude);
location.setSpeed(speed);
location.setBearing(bearing);

MockLocationProvider.simulate(location);
Log.d(TAG, "nmea sentence processed (lat, long: "+String.valueOf(latitude)+
" , "+String.valueOf(longitude)+")");

ResponseWriter.ok(client);
}

public void processGPGGA(SocketChannel client, String[] nmeaFields, String command) {
ResponseWriter.writeLine(client, "KO: Not Implemented Yet");
}

public boolean checkChecksum(String command) {
int from = command.indexOf("$");
int to = command.indexOf("*");
if (from == -1 || to == -1) {
return false;
}
String checkString = command.substring(from+1,to);
String checksum = command.substring(to+1);
int sum = 0;
for (int i=0; i<checkString.length(); i++) {
sum ^= (int)( checkString.charAt(i) );
}
String hexsum = Integer.toHexString(sum);
return hexsum.toLowerCase().equals(checksum.toLowerCase());
}

public long convertTimeAndDate(String time, String date) throws ParseException {
// UTC time, in milliseconds since January 1, 1970.

// suppressed because we set the timezone using setTimeZone in next step
@SuppressLint("SimpleDateFormat") SimpleDateFormat sf = new SimpleDateFormat("HHmmss ddMMyy");
sf.setTimeZone(TimeZone.getTimeZone("UTC"));
Date d = sf.parse(time+" "+date);
return d.getTime();
}

public double convertLatitude(String strLatitude, String qual) throws NumberFormatException {
double lat = Double.valueOf(strLatitude) / 100;
if (qual.equals("S")) {
lat *= -1;
}
return lat;
}

public double convertLongitude(String strLongitude, String qual) throws NumberFormatException {
double longitude = Double.valueOf(strLongitude) / 100;
if (qual.equals("W")) {
longitude *= -1;
}
return longitude;
}
}
}

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