Exporter: rather crash than hide lifecycle errors.

Part of #1187.

src/main/java/de/dennisguse/opentracks/io/file/exporter/CSVTrackExporter.java

@@ -153,25 +153,19 @@ public class CSVTrackExporter implements TrackExporter {
     }
 
     public void close() {
-        if (printWriter != null) {
         printWriter.flush();
         printWriter = null;
     }
-    }
 
     public void writeHeader(List<Column> columns) {
-        if (printWriter != null) {
         String columnNames = columns.stream().map(c -> c.columnName).reduce((s, s2) -> s + "," + s2).orElseThrow(() -> new RuntimeException("No columns defined"));
         printWriter.println("#" + columnNames);
     }
-    }
 
     public void writeTrackPoint(List<Column> columns, TrackPoint trackPoint) {
-        if (printWriter != null) {
         String columnNames = columns.stream().map(c -> c.extractor.apply(trackPoint)).reduce((s, s2) -> s + "," + s2).orElseThrow(() -> new RuntimeException("No columns defined"));
         printWriter.println(columnNames);
     }
-    }
 
     private static class Column {
         final String columnName;

src/main/java/de/dennisguse/opentracks/io/file/exporter/GPXTrackExporter.java

@@ -199,15 +199,12 @@ public class GPXTrackExporter implements TrackExporter {
     }
 
     public void close() {
-        if (printWriter != null) {
         printWriter.flush();
         printWriter = null;
     }
-    }
 
 
     public void writeHeader() {
-        if (printWriter != null) {
         printWriter.println("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
         printWriter.println("<gpx");
         printWriter.println("version=\"1.1\"");
@@ -229,13 +226,10 @@ public class GPXTrackExporter implements TrackExporter {
                 + " http://www.cluetrust.com/Schemas http://www.cluetrust.com/Schemas/gpxdata10.xsd"
                 + " http://opentracksapp.com/xmlschemas/v1 http://opentracksapp.com/xmlschemas/OpenTracks_v1.xsd\">");
     }
-    }
 
     public void writeFooter() {
-        if (printWriter != null) {
         printWriter.println("</gpx>");
     }
-    }
 
     private void writeMarkers(Track track) throws InterruptedException {
         try (Cursor cursor = contentProviderUtils.getMarkerCursor(track.getId(), null, -1)) {
@@ -254,7 +248,6 @@ public class GPXTrackExporter implements TrackExporter {
     }
 
     public void writeMarker(ZoneOffset zoneOffset, Marker marker) {
-        if (printWriter != null) {
         printWriter.println("<wpt " + formatLocation(marker.getLatitude(), marker.getLongitude()) + ">");
         if (marker.hasAltitude()) {
             printWriter.println("<ele>" + ALTITUDE_FORMAT.format(marker.getAltitude().toM()) + "</ele>");
@@ -265,10 +258,8 @@ public class GPXTrackExporter implements TrackExporter {
         printWriter.println("<type>" + StringUtils.formatCData(marker.getCategory()) + "</type>");
         printWriter.println("</wpt>");
     }
-    }
 
     public void writeBeginTrack(Track track) {
-        if (printWriter != null) {
         printWriter.println("<trk>");
         printWriter.println("<name>" + StringUtils.formatCData(track.getName()) + "</name>");
         printWriter.println("<desc>" + StringUtils.formatCData(track.getDescription()) + "</desc>");
@@ -291,13 +282,10 @@ public class GPXTrackExporter implements TrackExporter {
 
         printWriter.println("</extensions>");
     }
-    }
 
     public void writeEndTrack() {
-        if (printWriter != null) {
         printWriter.println("</trk>");
     }
-    }
 
     public void writeOpenSegment() {
         printWriter.println("<trkseg>");
@@ -310,8 +298,6 @@ public class GPXTrackExporter implements TrackExporter {
     public Distance writeTrackPoint(ZoneOffset zoneOffset, TrackPoint trackPoint, List<TrackPoint> sensorPoints, Distance trackDistance) {
         Distance cumulativeDistance = null;
 
-        if (printWriter != null) {
-
         printWriter.println("<trkpt " + formatLocation(trackPoint.getLatitude(), trackPoint.getLongitude()) + ">");
 
         if (trackPoint.hasAltitude()) {
@@ -370,7 +356,7 @@ public class GPXTrackExporter implements TrackExporter {
         }
 
         printWriter.println("</trkpt>");
-        }
+
         if (cumulativeDistance != null) {
             return cumulativeDistance;
         }

src/main/java/de/dennisguse/opentracks/io/file/exporter/KMLTrackExporter.java

@@ -212,14 +212,11 @@ public class KMLTrackExporter implements TrackExporter {
 
     @VisibleForTesting
     void close() {
-        if (printWriter != null) {
         printWriter.flush();
         printWriter = null;
     }
-    }
 
     private void writeHeader(List<Track> tracks) {
-        if (printWriter != null) {
         printWriter.println(
                 """
                         <?xml version="1.0" encoding="UTF-8"?>
@@ -252,25 +249,19 @@ public class KMLTrackExporter implements TrackExporter {
 
         printWriter.println("</Schema>");
     }
-    }
 
     private void writeFooter() {
-        if (printWriter != null) {
         printWriter.println("</Document>");
         printWriter.println("</kml>");
     }
-    }
 
     private void writeBeginMarkers(Track track) {
-        if (printWriter != null) {
         printWriter.println("<Folder>");
         printWriter.println("<name>" + StringUtils.formatCData(context.getString(R.string.track_markers, track.getName())) + "</name>");
         printWriter.println("<open>1</open>");
     }
-    }
 
     private void writeMarker(Marker marker, ZoneOffset zoneOffset) {
-        if (printWriter != null) {
         boolean existsPhoto = MarkerUtils.buildInternalPhotoFile(context, marker.getTrackId(), marker.getPhotoURI()) != null;
         if (marker.hasPhoto() && exportPhotos && existsPhoto) {
             float heading = getHeading(marker.getTrackId(), marker.getLocation());
@@ -279,30 +270,22 @@ public class KMLTrackExporter implements TrackExporter {
             writePlacemark(marker.getName(), marker.getCategory(), marker.getDescription(), marker.getLocation(), zoneOffset);
         }
     }
-    }
 
     private void writeEndMarkers() {
-        if (printWriter != null) {
         printWriter.println("</Folder>");
     }
-    }
 
     private void writeMultiTrackBegin() {
-        if (printWriter != null) {
         printWriter.println("<Folder id=\"tracks\">");
         printWriter.println("<name>" + context.getString(R.string.generic_tracks) + "</name>");
         printWriter.println("<open>1</open>");
     }
-    }
 
     private void writeMultiTrackEnd() {
-        if (printWriter != null) {
         printWriter.println("</Folder>");
     }
-    }
 
     private void writeBeginTrack(Track track) {
-        if (printWriter != null) {
         printWriter.println("<Placemark>");
 
         printWriter.println("<name>" + StringUtils.formatCData(track.getName()) + "</name>");
@@ -316,19 +299,15 @@ public class KMLTrackExporter implements TrackExporter {
         printWriter.println("<altitudeMode>absolute</altitudeMode>");
         printWriter.println("<interpolate>1</interpolate>");
     }
-    }
 
 
     private void writeEndTrack() {
-        if (printWriter != null) {
         printWriter.println("</MultiTrack>");
         printWriter.println("</Placemark>");
     }
-    }
 
     @VisibleForTesting
     void writeOpenSegment() {
-        if (printWriter != null) {
         printWriter.println("<Track>");
         speedList.clear();
         distanceList.clear();
@@ -340,11 +319,9 @@ public class KMLTrackExporter implements TrackExporter {
         accuracyHorizontal.clear();
         accuracyVertical.clear();
     }
-    }
 
     @VisibleForTesting
     void writeCloseSegment() {
-        if (printWriter != null) {
         printWriter.println("<ExtendedData>");
         printWriter.println("<SchemaData schemaUrl=\"#" + SCHEMA_ID + "\">");
         if (speedList.stream().anyMatch(Objects::nonNull)) {
@@ -378,11 +355,9 @@ public class KMLTrackExporter implements TrackExporter {
         printWriter.println("</ExtendedData>");
         printWriter.println("</Track>");
     }
-    }
 
     @VisibleForTesting
     void writeTrackPoint(ZoneOffset zoneOffset, TrackPoint trackPoint) {
-        if (printWriter != null) {
         printWriter.println("<when>" + getTime(zoneOffset, trackPoint.getLocation()) + "</when>");
 
         if (trackPoint.hasLocation()) {
@@ -402,7 +377,6 @@ public class KMLTrackExporter implements TrackExporter {
         accuracyHorizontal.add(trackPoint.hasHorizontalAccuracy() ? (float) trackPoint.getHorizontalAccuracy().toM() : null);
         accuracyVertical.add(trackPoint.hasVerticalAccuracy() ? (float) trackPoint.getVerticalAccuracy().toM() : null);
     }
-    }
 
     /**
      * Writes the simple array data.