Index: /applications/editors/josm/plugins/photo_geotagging/src/org/openstreetmap/josm/plugins/photo_geotagging/GeotaggingAction.java
===================================================================
--- /applications/editors/josm/plugins/photo_geotagging/src/org/openstreetmap/josm/plugins/photo_geotagging/GeotaggingAction.java	(revision 35776)
+++ /applications/editors/josm/plugins/photo_geotagging/src/org/openstreetmap/josm/plugins/photo_geotagging/GeotaggingAction.java	(revision 35777)
@@ -209,5 +209,5 @@
 
         private boolean canceled = false;
-        private Boolean override_backup = null;
+        Boolean override_backup = null;
 
         private File fileFrom;
Index: /applications/editors/josm/plugins/photo_geotagging/test/unit/org/openstreetmap/josm/plugins/photo_geotagging/GeotaggingActionTest.java
===================================================================
--- /applications/editors/josm/plugins/photo_geotagging/test/unit/org/openstreetmap/josm/plugins/photo_geotagging/GeotaggingActionTest.java	(revision 35777)
+++ /applications/editors/josm/plugins/photo_geotagging/test/unit/org/openstreetmap/josm/plugins/photo_geotagging/GeotaggingActionTest.java	(revision 35777)
@@ -0,0 +1,56 @@
+package org.openstreetmap.josm.plugins.photo_geotagging;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.StandardCopyOption;
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.Test;
+import org.openstreetmap.josm.TestUtils;
+import org.openstreetmap.josm.data.coor.LatLon;
+import org.openstreetmap.josm.gui.layer.geoimage.ImageEntry;
+import org.openstreetmap.josm.plugins.photo_geotagging.GeotaggingAction.GeoTaggingRunnable;
+
+public class GeotaggingActionTest {
+
+    @Test
+    public void testProcessEntries() throws IOException {
+        File original = new File(TestUtils.getTestDataRoot(), "_DSC1234.jpg");
+        assertTrue(original.exists());
+
+        File copy = new File(TestUtils.getTestDataRoot(), "_DSC1234.copy.jpg");
+        if (copy.exists()) copy.delete();
+        //this method will actually override the file, so use a copy:
+        Files.copy(original.toPath(), copy.toPath(), StandardCopyOption.REPLACE_EXISTING);
+
+        ImageEntry entry = new ImageEntry(copy);
+        entry.setPos(new LatLon(1, 2));
+        List<ImageEntry> list = Arrays.asList(entry);
+
+        GeoTaggingRunnable runnable = new GeotaggingAction.GeoTaggingRunnable(list, true, 0);
+        //this causes some warnings from the PleaseWaitRunnable because not all resources are available
+        //but that's irrelevant to the test
+        runnable.getProgressMonitor().beginTask("test");
+        runnable.override_backup = true;
+        assertEquals(1, runnable.processEntries(list, false).size());
+        assertEquals(0, runnable.processEntries(list, true).size());
+        //test if overriding backup works:
+        assertEquals(0, runnable.processEntries(list, true).size());
+
+        runnable = new GeotaggingAction.GeoTaggingRunnable(list, false, 0);
+        runnable.getProgressMonitor().beginTask("test");
+        //file is now "repaired" from operation above and lossless writing should work:
+        assertEquals(0, runnable.processEntries(list, false).size());
+        assertEquals(0, runnable.processEntries(list, true).size());
+
+        File backup = new File(TestUtils.getTestDataRoot(), "_DSC1234.copy.jpg_");
+        assertTrue(backup.exists());
+        backup.delete();
+        copy.delete();
+    }
+}