Cleanup base directory selection, use Context.getExternalFilesDirs and request WRITE_EXTERNAL_STORAGE permission, use AndroidX and raise minSdkVersion to 14. Use File instead of plain Strings for paths in some places, use try-with-resources, and some other small improvements.

brouter-core/src/main/java/btools/router/RoutingEngine.java

@@ -41,7 +41,7 @@ public class RoutingEngine extends Thread
 
   private volatile boolean terminated;
 
-  protected String segmentDir;
+  protected File segmentDir;
   private String outfileBase;
   private String logfileBase;
   private boolean infoLogEnabled;
@@ -64,7 +64,7 @@ public class RoutingEngine extends Thread
 
   private boolean directWeaving = !Boolean.getBoolean( "disableDirectWeaving" );
 
-  public RoutingEngine( String outfileBase, String logfileBase, String segmentDir,
+  public RoutingEngine( String outfileBase, String logfileBase, File segmentDir,
           List<OsmNodeNamed> waypoints, RoutingContext rc )
   {
     this.segmentDir = segmentDir;

brouter-core/src/main/java/btools/router/RoutingHelper.java

@@ -11,20 +11,20 @@ import btools.mapaccess.StorageConfigHelper;
 
 public final class RoutingHelper
 {
-    public static File getAdditionalMaptoolDir( String segmentDir )
+    public static File getAdditionalMaptoolDir( File segmentDir )
     {
     	return StorageConfigHelper.getAdditionalMaptoolDir(segmentDir);
     }
 
-    public static File getSecondarySegmentDir( String segmentDir )
+    public static File getSecondarySegmentDir( File segmentDir )
     {
     	return StorageConfigHelper.getSecondarySegmentDir(segmentDir);
     }
     
     
-    public static boolean hasDirectoryAnyDatafiles( String segmentDir )
+    public static boolean hasDirectoryAnyDatafiles( File segmentDir )
     {
-        if ( hasAnyDatafiles( new File( segmentDir ) ) )
+        if ( hasAnyDatafiles( segmentDir ) )
         {
         	return true;
         }

brouter-mapaccess/src/main/java/btools/mapaccess/NodesCache.java

@@ -56,10 +56,10 @@ public final class NodesCache
     return "collecting=" + garbageCollectionEnabled + " noGhosts=" + ghostCleaningDone + " cacheSum=" + cacheSum + " cacheSumClean=" + cacheSumClean + " ghostSum=" + ghostSum + " ghostWakeup=" + ghostWakeup ;
   }
 
-  public NodesCache( String segmentDir, BExpressionContextWay ctxWay, boolean forceSecondaryData, long maxmem, NodesCache oldCache, boolean detailed )
+  public NodesCache( File segmentDir, BExpressionContextWay ctxWay, boolean forceSecondaryData, long maxmem, NodesCache oldCache, boolean detailed )
   {
     this.maxmemtiles = maxmem / 8;
-    this.segmentDir = new File( segmentDir );
+    this.segmentDir = segmentDir;
     this.nodesMap = new OsmNodesMap();
     this.nodesMap.maxmem = (2L*maxmem) / 3L;
     this.expCtxWay = ctxWay;
@@ -77,7 +77,7 @@ public final class NodesCache
     first_file_access_name = null;
 
     if ( !this.segmentDir.isDirectory() )
-      throw new RuntimeException( "segment directory " + segmentDir + " does not exist" );
+      throw new RuntimeException( "segment directory " + segmentDir.getAbsolutePath () + " does not exist" );
 
     if ( oldCache != null )
     {

brouter-mapaccess/src/main/java/btools/mapaccess/StorageConfigHelper.java

@@ -11,21 +11,21 @@ import java.io.FileReader;
 
 public class StorageConfigHelper
 {
-  public static File getSecondarySegmentDir( String segmentDir )
+  public static File getSecondarySegmentDir( File segmentDir )
   {
     return getStorageLocation( segmentDir, "secondary_segment_dir=" );
   }
 
-  public static File getAdditionalMaptoolDir( String segmentDir )
+  public static File getAdditionalMaptoolDir( File segmentDir )
   {
     return getStorageLocation( segmentDir, "additional_maptool_dir=" );
   }
 
-  private static File getStorageLocation( String segmentDir, String tag )
+  private static File getStorageLocation( File segmentDir, String tag )
   {
     File res = null;
     BufferedReader br = null;
-    String configFile = segmentDir + "/storageconfig.txt";
+    File configFile = new File (segmentDir, "storageconfig.txt");
     try
     {
       br = new BufferedReader( new FileReader( configFile ) );
@@ -38,7 +38,7 @@ public class StorageConfigHelper
         if ( line.startsWith( tag ) )
         {
           String path = line.substring( tag.length() ).trim();
-          res = path.startsWith( "/" ) ? new File( path ) : new File( new File( segmentDir ), path );
+          res = path.startsWith( "/" ) ? new File( path ) : new File( segmentDir, path );
           if ( !res.exists() ) res = null;
           break;
         }

brouter-routing-app/build.gradle

@@ -7,7 +7,7 @@ android {
 
     defaultConfig {
         applicationId "btools.routingapp"
-        minSdkVersion 10
+        minSdkVersion 14
         targetSdkVersion 29
         versionCode 41
         versionName "1.6.1"
@@ -27,6 +27,7 @@ android {
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
 
+    implementation 'androidx.appcompat:appcompat:1.1.0'
     implementation project(':brouter-mapaccess')
     implementation project(':brouter-core')
     implementation project(':brouter-expressions')

brouter-routing-app/src/main/java/btools/routingapp/BInstallerView.java

@@ -58,7 +58,7 @@ public class BInstallerView extends View
     private boolean tilesVisible = false;
     
     private long availableSize;
-    private String baseDir;
+    private File baseDir;
     
     private boolean isDownloading = false;
     private volatile boolean downloadCanceled = false;
@@ -207,7 +207,7 @@ public class BInstallerView extends View
     
     private void deleteRawTracks()
     {
-      File modeDir = new File( baseDir + "/brouter/modes" );
+      File modeDir = new File( baseDir, "brouter/modes" );
       String[] fileNames = modeDir.list();
       if ( fileNames == null ) return;
       for( String fileName : fileNames )
@@ -224,9 +224,9 @@ public class BInstallerView extends View
     {
       clearTileSelection( MASK_INSTALLED_RD5 | MASK_CURRENT_RD5 );
 
-      scanExistingFiles( new File( baseDir + "/brouter/segments4" ) );
+      scanExistingFiles( new File( baseDir, "brouter/segments4" ) );
       
-      File secondary = RoutingHelper.getSecondarySegmentDir( baseDir + "/brouter/segments4" );
+      File secondary = RoutingHelper.getSecondarySegmentDir( new File ( baseDir, "brouter/segments4" ) );
       if ( secondary != null )
       {
           scanExistingFiles( secondary );
@@ -235,7 +235,7 @@ public class BInstallerView extends View
       availableSize = -1;
       try
       {
-        StatFs stat = new StatFs(baseDir);
+        StatFs stat = new StatFs(baseDir.getAbsolutePath ());
         availableSize = (long)stat.getAvailableBlocks()*stat.getBlockSize();
       }
       catch (Exception e) { /* ignore */ }
@@ -472,7 +472,7 @@ float tx, ty;
         int tidx = gridPos2Tileindex( ix, iy );
         if ( ( tileStatus[tidx] & MASK_DELETED_RD5 ) != 0 )
         {
-          new File( baseDir + "/brouter/segments4/" + baseNameForTile( tidx ) + ".rd5").delete();
+          new File( baseDir, "brouter/segments4/" + baseNameForTile( tidx ) + ".rd5").delete();
         }
       }
     }
@@ -667,7 +667,7 @@ float tx, ty;
               OutputStream output = null;
               HttpURLConnection connection = null;
               String surl = sUrls[0];
-              String fname = null;
+              File fname = null;
               File tmp_file = null;
               try
               {
@@ -676,17 +676,16 @@ float tx, ty;
                     int slidx = surl.lastIndexOf( "segments4/" );
                     String name = surl.substring( slidx+10 );
                     String surlBase = surl.substring( 0, slidx+10 );
-                    fname = baseDir + "/brouter/segments4/" + name;
+                    fname = new File (baseDir, "brouter/segments4/" + name);
 
                     boolean delta = true;
 
-                    File targetFile = new File( fname );
+                    if ( fname.exists() )
-                    if ( targetFile.exists() )
                     {
                       updateProgress( "Calculating local checksum.." );
                     
                       // first check for a delta file
-                      String md5 = Rd5DiffManager.getMD5( targetFile );
+                      String md5 = Rd5DiffManager.getMD5( fname );
                       String surlDelta = surlBase + "diff/" + name.replace( ".rd5", "/" + md5 + ".rd5diff" );
                       
                       URL urlDelta = new URL(surlDelta);
@@ -728,7 +727,7 @@ float tx, ty;
                     // download the file
                     input = connection.getInputStream();
                     
-                    tmp_file = new File( fname + ( delta ? "_diff" : "_tmp" ) );
+                    tmp_file = new File( fname.getAbsolutePath() + ( delta ? "_diff" : "_tmp" ) );
                     output = new FileOutputStream( tmp_file );
 
                     byte data[] = new byte[4096];
@@ -768,7 +767,7 @@ float tx, ty;
                       updateProgress( "Applying delta.." );
                       File diffFile = tmp_file;
                       tmp_file = new File( fname + "_tmp" );
-                      Rd5DiffTool.recoverFromDelta( targetFile, diffFile, tmp_file, this );
+                      Rd5DiffTool.recoverFromDelta( fname, diffFile, tmp_file, this );
                       diffFile.delete();
                     }
                     if (isDownloadCanceled())
@@ -781,9 +780,9 @@ float tx, ty;
                       String check_result = PhysicalFile.checkFileIntegrity( tmp_file );
                       if ( check_result != null ) return check_result;
 
-                      if ( !tmp_file.renameTo( targetFile ) )
+                      if ( !tmp_file.renameTo( fname ) )
                       {
-                        return "Could not rename to " + targetFile;
+                        return "Could not rename to " + fname.getAbsolutePath();
                       }
                       deleteRawTracks(); // invalidate raw-tracks after data update
                     }

brouter-routing-app/src/main/java/btools/routingapp/BRouterActivity.java

@@ -1,5 +1,6 @@
 package btools.routingapp;
 
+import java.io.File;
 import java.text.DecimalFormat;
 import java.util.ArrayList;
 import java.util.HashSet;
@@ -13,16 +14,22 @@ import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
+import android.content.pm.PackageManager;
 import android.net.ConnectivityManager;
 import android.os.Bundle;
+import android.os.Environment;
 import android.os.PowerManager;
 import android.os.PowerManager.WakeLock;
 import android.os.StatFs;
 import android.speech.tts.TextToSpeech.OnInitListener;
+import android.util.Log;
 import android.widget.EditText;
+
+import androidx.core.app.ActivityCompat;
+
 import btools.router.OsmNodeNamed;
 
-public class BRouterActivity extends Activity implements OnInitListener
+public class BRouterActivity extends Activity implements OnInitListener, ActivityCompat.OnRequestPermissionsResultCallback
 {
   private static final int DIALOG_SELECTPROFILE_ID = 1;
   private static final int DIALOG_EXCEPTION_ID = 2;
@@ -268,13 +275,14 @@ public class BRouterActivity extends Activity implements OnInitListener
         public void onClick( DialogInterface dialog, int whichButton )
         {
           String basedir = input.getText().toString();
-          mBRouterView.startSetup( basedir, true );
+          mBRouterView.startSetup( new File(basedir), true );
         }
       } );
       return builder.create();
     case DIALOG_SELECTBASEDIR_ID:
       builder = new AlertDialog.Builder( this );
-      builder.setTitle( "Select an SDCARD base dir:" );
+      builder.setTitle( "Choose brouter data base dir:" );
+      // builder.setMessage( message );
       builder.setSingleChoiceItems( basedirOptions, 0, new DialogInterface.OnClickListener()
       {
         @Override
@@ -428,7 +436,7 @@ public class BRouterActivity extends Activity implements OnInitListener
   private String[] availableProfiles;
   private String selectedProfile = null;
 
-  private List<String> availableBasedirs;
+  private List<File> availableBasedirs;
   private String[] basedirOptions;
   private int selectedBasedir;
 
@@ -484,22 +492,21 @@ public class BRouterActivity extends Activity implements OnInitListener
   }
 
   @SuppressWarnings("deprecation")
-  public void selectBasedir( List<String> items, String defaultBasedir, String message )
+  public void selectBasedir( ArrayList<File> items, String defaultBasedir, String message )
   {
     this.defaultbasedir = defaultBasedir;
     this.message = message;
-    availableBasedirs = new ArrayList<String>();
+    availableBasedirs = items;
     ArrayList<Long> dirFreeSizes = new ArrayList<Long>();
-    for ( String d : items )
+    for ( File f : items )
     {
       long size = 0L;
       try
       {
-        StatFs stat = new StatFs( d );
+        StatFs stat = new StatFs( f.getAbsolutePath() );
         size = (long) stat.getAvailableBlocks() * stat.getBlockSize();
       }
       catch (Exception e) { /* ignore */ }
-      availableBasedirs.add( d );
       dirFreeSizes.add( Long.valueOf( size ) );
     }
 
@@ -510,7 +517,7 @@ public class BRouterActivity extends Activity implements OnInitListener
     {
       basedirOptions[bdidx++] = availableBasedirs.get( idx ) + " (" + df.format( dirFreeSizes.get( idx ) / 1024. / 1024. / 1024. ) + " GB free)";
     }
-    basedirOptions[bdidx] = "Other";
+    basedirOptions[bdidx] = "Enter path manually";
 
     showDialog( DIALOG_SELECTBASEDIR_ID );
   }
@@ -644,4 +651,15 @@ public class BRouterActivity extends Activity implements OnInitListener
   public void onInit( int i )
   {
   }
+
+  @Override
+  public void onRequestPermissionsResult (int requestCode, String[] permissions, int[] grantResults) {
+    if (requestCode == 0) {
+      if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
+        mBRouterView.startSetup(null, true);
+      } else {
+        mBRouterView.init();
+      }
+    }
+  }
 }

brouter-routing-app/src/main/java/btools/routingapp/BRouterService.java

@@ -11,6 +11,7 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.ByteArrayOutputStream;
+import java.nio.charset.StandardCharsets;
 import java.util.zip.GZIPOutputStream;
 import java.util.ArrayList;
 
@@ -58,7 +59,7 @@ public class BRouterService extends Service
         if ( configInput != null ) try { configInput.close(); } catch (Exception ee) {}
       }
       worker.baseDir = baseDir;
-      worker.segmentDir = baseDir + "/brouter/segments4";
+      worker.segmentDir = new File (baseDir, "brouter/segments4" );
 
       String remoteProfile = params.getString( "remoteProfile" );
 
@@ -85,9 +86,9 @@ public class BRouterService extends Service
           try
           {
             ByteArrayOutputStream baos = new ByteArrayOutputStream();
-            baos.write( "z64".getBytes("UTF-8") ); // marker prefix
+            baos.write( "z64".getBytes(StandardCharsets.UTF_8) ); // marker prefix
             OutputStream os = new GZIPOutputStream( baos );
-            byte[] ab = gpxMessage.getBytes("UTF-8");
+            byte[] ab = gpxMessage.getBytes(StandardCharsets.UTF_8);
             gpxMessage = null;
             os.write( ab );
             ab = null;

brouter-routing-app/src/main/java/btools/routingapp/BRouterView.java

@@ -12,6 +12,7 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 import java.util.Set;
 import java.util.StringTokenizer;
@@ -19,16 +20,24 @@ import java.util.TreeMap;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipInputStream;
 
+import android.Manifest;
 import android.app.Activity;
 import android.content.Context;
+import android.content.pm.PackageManager;
 import android.content.res.AssetManager;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Paint;
 import android.os.Environment;
 import android.util.DisplayMetrics;
+import android.util.Log;
 import android.view.View;
 import android.widget.Toast;
+
+import androidx.core.app.ActivityCompat;
+import androidx.core.content.ContextCompat;
+import androidx.core.os.EnvironmentCompat;
+
 import btools.expressions.BExpressionContextWay;
 import btools.expressions.BExpressionMetaData;
 import btools.mapaccess.OsmNode;
@@ -57,10 +66,11 @@ public class BRouterView extends View
   private List<OsmNodeNamed> nogoVetoList;
   private OsmTrack rawTrack;
 
-  private String modesDir;
+  private File retryBaseDir;
-  private String tracksDir;
+  private File modesDir;
-  private String segmentDir;
+  private File tracksDir;
-  private String profileDir;
+  private File segmentDir;
+  private File profileDir;
   private String profilePath;
   private String profileName;
   private String sourceHint;
@@ -104,14 +114,13 @@ public class BRouterView extends View
       imgh = metrics.heightPixels;
 
       // get base dir from private file
-      String baseDir = ConfigHelper.getBaseDir( getContext() );
+      File baseDir = ConfigHelper.getBaseDir( getContext() );
       // check if valid
       boolean bdValid = false;
       if ( baseDir != null )
       {
-        File bd = new File( baseDir );
+        bdValid = baseDir.isDirectory();
-        bdValid = bd.isDirectory();
+        File brd = new File( baseDir, "brouter" );
-        File brd = new File( bd, "brouter" );
         if ( brd.isDirectory() )
         {
           startSetup( baseDir, false );
@@ -135,64 +144,59 @@ public class BRouterView extends View
     }
   }
 
-  public void startSetup( String baseDir, boolean storeBasedir )
+  public void startSetup( File baseDir, boolean storeBasedir )
   {
-    cor = null;
+    if (baseDir == null) {
-    try
+      baseDir = retryBaseDir;
-    {
+      retryBaseDir = null;
-      File fbd = new File( baseDir );
-      if ( !fbd.isDirectory() )
-      {
-        throw new IllegalArgumentException( "Base-directory " + baseDir + " is not a directory " );
-      }
-      if ( storeBasedir )
-      {
-        // Android 4.4 patch: try extend the basedir if not valid
-        File td = new File( fbd, "brouter" );
-        try
-        {
-          td.mkdir();
-        }
-        catch (Exception e) {}
-        if ( !td.isDirectory() )
-        {
-          File td1 = new File( fbd, "Android/data/btools/routingapp" );
-          try
-          {
-            td1.mkdirs();
-          }
-          catch (Exception e){}
-          td = new File( td1, "brouter" );
-          try
-          {
-            td.mkdir();
-          }
-          catch (Exception e) {}
-          if ( td.isDirectory() )
-            fbd = td1;
     }
 
+    if ( storeBasedir )
+    {
+      File td = new File( baseDir, "brouter" );
+      try
+      {
+        td.mkdirs();
+      }
+      catch (Exception e) {
+        Log.d ("BRouterView", "Error creating base directory: " + e.getMessage());
+        e.printStackTrace();
+      }
+
+      if ( !td.isDirectory() ) {
+        if (ContextCompat.checkSelfPermission (getContext(), Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED) {
+          retryBaseDir = baseDir;
+          ActivityCompat.requestPermissions ((BRouterActivity) getContext(), new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 0);
+        } else {
+          ( (BRouterActivity) getContext() ).selectBasedir( getStorageDirectories (), guessBaseDir(), "Cannot access " + baseDir.getAbsolutePath () + "; select another");
+        }
+        return;
+      }
       ConfigHelper.writeBaseDir( getContext(), baseDir );
     }
-      String basedir = fbd.getAbsolutePath();
+    try
+    {
+      cor = null;
+
+      String basedir = baseDir.getAbsolutePath();
       AppLogger.log( "using basedir: " + basedir );
 
       String version = "v1.6.1";
 
       // create missing directories
-      assertDirectoryExists( "project directory", basedir + "/brouter", null, null );
+      assertDirectoryExists( "project directory", new File (basedir, "brouter"), null, null );
-      segmentDir = basedir + "/brouter/segments4";
+      segmentDir = new File (basedir, "/brouter/segments4");
       if ( assertDirectoryExists( "data directory", segmentDir, "segments4.zip", null ) )
       {
         ConfigMigration.tryMigrateStorageConfig(
               new File( basedir + "/brouter/segments3/storageconfig.txt" ),
               new File( basedir + "/brouter/segments4/storageconfig.txt" ) );
       }
-      profileDir = basedir + "/brouter/profiles2";
+      profileDir = new File (basedir, "brouter/profiles2");
       assertDirectoryExists( "profile directory", profileDir, "profiles2.zip", version );
-      modesDir = basedir + "/brouter/modes";
+      modesDir = new File (basedir, "/brouter/modes");
       assertDirectoryExists( "modes directory", modesDir, "modes.zip", version );
-      assertDirectoryExists( "readmes directory", basedir + "/brouter/readmes", "readmes.zip", version );
+      assertDirectoryExists( "readmes directory", new File (basedir, "brouter/readmes"), "readmes.zip", version );
 
       int deviceLevel =  android.os.Build.VERSION.SDK_INT;
       int targetSdkVersion = getContext().getApplicationInfo().targetSdkVersion;
@@ -219,17 +223,18 @@ public class BRouterView extends View
 
       if ( cor.tracksdir != null )
       {
-        tracksDir = cor.basedir + cor.tracksdir;
+        tracksDir = new File (cor.basedir, cor.tracksdir);
         assertDirectoryExists( "track directory", tracksDir, null, null );
 
         // output redirect: look for a pointerfile in tracksdir
-        File tracksDirPointer = new File( tracksDir + "/brouter.redirect" );
+        File tracksDirPointer = new File( tracksDir, "brouter.redirect" );
         if ( tracksDirPointer.isFile() )
         {
-          tracksDir = readSingleLineFile( tracksDirPointer );
+          String tracksDirStr = readSingleLineFile( tracksDirPointer );
-          if ( tracksDir == null )
+          if ( tracksDirStr == null )
             throw new IllegalArgumentException( "redirect pointer file is empty: " + tracksDirPointer );
-          if ( !( new File( tracksDir ).isDirectory() ) )
+          tracksDir = new File (tracksDirStr);
+          if ( !( tracksDir.isDirectory() ) )
             throw new IllegalArgumentException( "redirect pointer file " + tracksDirPointer + " does not point to a directory: " + tracksDir );
         }
         else
@@ -248,10 +253,10 @@ public class BRouterView extends View
       }
       if ( tracksDir == null )
       {
-        tracksDir = basedir + "/brouter"; // fallback
+        tracksDir = new File (basedir, "router"); // fallback
       }
 
-      String[] fileNames = new File( profileDir ).list();
+      String[] fileNames = profileDir.list();
       ArrayList<String> profiles = new ArrayList<String>();
 
       boolean lookupsFound = false;
@@ -387,7 +392,7 @@ public class BRouterView extends View
     {
       if ( wp.name.equals( waypoint ) )
       {
-        if ( wp.ilat != 0 || wp.ilat != 0 )
+        if ( wp.ilat != 0 || wp.ilon != 0 )
         {
           int nwp = wpList.size();
           if ( nwp == 0 || wpList.get( nwp-1 ) != wp )
@@ -513,10 +518,10 @@ public class BRouterView extends View
       OsmNode prev = null;
       for ( OsmNode n : wpList )
       {
-        maxlon = n.ilon > maxlon ? n.ilon : maxlon;
+        maxlon = Math.max(n.ilon, maxlon);
-        minlon = n.ilon < minlon ? n.ilon : minlon;
+        minlon = Math.min(n.ilon, minlon);
-        maxlat = n.ilat > maxlat ? n.ilat : maxlat;
+        maxlat = Math.max(n.ilat, maxlat);
-        minlat = n.ilat < minlat ? n.ilat : minlat;
+        minlat = Math.min(n.ilat, minlat);
         if ( prev != null )
         {
           plain_distance += n.calcDistance( prev );
@@ -536,7 +541,7 @@ public class BRouterView extends View
 
       scaleLon = imgw / ( difflon * 1.5 );
       scaleLat = imgh / ( difflat * 1.5 );
-      scaleMeter2Pixel = scaleLon < scaleLat ? scaleLon : scaleLat;
+      scaleMeter2Pixel = Math.min(scaleLon, scaleLat);
       scaleLon = scaleMeter2Pixel*dlon2m;
       scaleLat = scaleMeter2Pixel*dlat2m;
 
@@ -570,18 +575,16 @@ public class BRouterView extends View
     }
   }
 
-  private boolean assertDirectoryExists( String message, String path, String assetZip, String versionTag )
+  private boolean assertDirectoryExists( String message, File path, String assetZip, String versionTag )
   {
-    File f = new File( path );
+    boolean exists = path.exists();
-
-    boolean exists = f.exists();
     if ( !exists )
     {
-      f.mkdirs();
+      path.mkdirs();
     }
     if ( versionTag != null )
     {
-      File vtag = new File( f, versionTag );
+      File vtag = new File( path, versionTag );
       try
       {
         exists = !vtag.createNewFile();
@@ -606,7 +609,7 @@ public class BRouterView extends View
             if ( ze == null )
               break;
             String name = ze.getName();
-            File outfile = new File( f, name );
+            File outfile = new File( path, name );
             outfile.getParentFile().mkdirs();
             FileOutputStream fos = new FileOutputStream( outfile );
 
@@ -629,7 +632,7 @@ public class BRouterView extends View
 
       }
     }
-    if ( !f.exists() || !f.isDirectory() )
+    if ( !path.exists() || !path.isDirectory() )
       throw new IllegalArgumentException( message + ": " + path + " cannot be created" );
     return false;
   }
@@ -1071,76 +1074,29 @@ public class BRouterView extends View
 
   private String readSingleLineFile( File f )
   {
-    BufferedReader br = null;
+    try (  FileInputStream fis = new FileInputStream (f);
-    try
+           InputStreamReader isr = new InputStreamReader (fis);
-    {
+           BufferedReader br = new BufferedReader (isr)) {
-      br = new BufferedReader( new InputStreamReader( new FileInputStream( f ) ) );
       return br.readLine();
     }
     catch (Exception e)
     {
       return null;
     }
-    finally
-    {
-      if ( br != null )
-        try
-        {
-          br.close();
-        }
-        catch (Exception ee)
-        {
   }
+
+  private ArrayList<File> getStorageDirectories () {
+    ArrayList<File> list = new ArrayList<File>(Arrays.asList(getContext().getExternalFilesDirs(null)));
+    ArrayList<File> res = new ArrayList<File>();
+
+    for (File f : list) {
+      if (f != null) {
+        if (EnvironmentCompat.getStorageState(f).equals(Environment.MEDIA_MOUNTED))
+          res.add (f);
       }
     }
 
-  private List<String> getStorageDirectories()
+//    res.add(getContext().getFilesDir());
-  {
-    ArrayList<String> res = new ArrayList<String>();
-    
-    // check write access on internal sd
-    try
-    {
-      File sd = Environment.getExternalStorageDirectory();
-      File testDir = new File( sd, "brouter" );
-      boolean didExist = testDir.isDirectory();
-      if ( !didExist )
-      {
-        testDir.mkdir();
-      }
-      File testFile = new File( testDir, "test" + System.currentTimeMillis() );
-      testFile.createNewFile();
-      if ( testFile.exists() )
-      {
-        testFile.delete();
-        res.add( sd.getPath() );
-      }
-      if ( !didExist )
-      {
-        testDir.delete();
-      }
-    }
-    catch( Throwable t )
-    {
-      // ignore
-    }
-    
-
-    try
-    {
-      Method method = Context.class.getDeclaredMethod("getExternalFilesDirs", new Class[]{ String.class } );
-      File[] paths = (File[])method.invoke( getContext(), new Object[1] );
-      for( File path : paths )
-      {
-        res.add( path.getPath() );
-      }
-    }
-    catch( Exception e )
-    {
-      res.add( e.toString() );
-      res.add( Environment.getExternalStorageDirectory().getPath() );
-    }
     return res;
   }
-
 }

brouter-routing-app/src/main/java/btools/routingapp/BRouterWorker.java

@@ -17,7 +17,7 @@ import btools.router.RoutingEngine;
 public class BRouterWorker
 {
   public String baseDir;
-  public String segmentDir;
+  public File segmentDir;
   public String profileName;
   public String profilePath;
   public String rawTrackPath;

brouter-routing-app/src/main/java/btools/routingapp/ConfigHelper.java

@@ -6,59 +6,35 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
+import java.io.File;
 
 import android.content.Context;
 
 public class ConfigHelper
 {
-  public static String getBaseDir( Context ctx )
+  public static File getBaseDir( Context ctx )
   {
     // get base dir from private file
-    InputStream configInput = null;
+
-    try
+    try (InputStream configInput = ctx.openFileInput( "config15.dat" );
-    {
+         InputStreamReader isr = new InputStreamReader( configInput );
-      configInput = ctx.openFileInput( "config15.dat" );
+         BufferedReader br = new BufferedReader(isr)) {
-      BufferedReader br = new BufferedReader( new InputStreamReader( configInput ) );
+      return new File ( br.readLine() );
-      return br.readLine();
     }
     catch (Exception e)
     {
       return null;
     }
-    finally
-    {
-      if ( configInput != null )
-      {
-        try
-        {
-          configInput.close();
-        }
-        catch (Exception ee)
-        {
-        }
-      }
-    }
   }
 
-  public static void writeBaseDir( Context ctx, String baseDir )
+  public static void writeBaseDir( Context ctx, File baseDir )
   {
-    BufferedWriter bw = null;
+    try (OutputStream configOutput = ctx.openFileOutput( "config15.dat", Context.MODE_PRIVATE );
-    try
+         OutputStreamWriter osw = new OutputStreamWriter( configOutput );
-    {
+         BufferedWriter bw = new BufferedWriter( osw)) {
-      OutputStream configOutput = ctx.openFileOutput( "config15.dat", Context.MODE_PRIVATE );
+      bw.write( baseDir.getAbsolutePath () );
-      bw = new BufferedWriter( new OutputStreamWriter( configOutput ) );
-      bw.write( baseDir );
       bw.write( '\n' );
     }
     catch (Exception e){ /* ignore */ }
-    finally
-    {
-      if ( bw != null )
-        try
-        {
-          bw.close();
-        }
-        catch (Exception ee) { /* ignore */ }
-    }
   }
 }

brouter-routing-app/src/main/java/btools/routingapp/ConfigMigration.java

@@ -87,17 +87,17 @@ public class ConfigMigration
     }
   }
 
-  public static File saveAdditionalMaptoolDir( String segmentDir, String value )
+  public static File saveAdditionalMaptoolDir( File segmentDir, String value )
   {
     return saveStorageLocation( segmentDir, "additional_maptool_dir=", value );
   }
 
-  private static File saveStorageLocation( String segmentDir, String tag, String value )
+  private static File saveStorageLocation( File segmentDir, String tag, String value )
   {
     File res = null;
     BufferedReader br = null;
     BufferedWriter bw = null;
-    String configFile = segmentDir + "/storageconfig.txt";
+    File configFile = new File (segmentDir, "storageconfig.txt");
     List<String> lines = new ArrayList<String>();
     try
     {

brouter-routing-app/src/main/java/btools/routingapp/CoordinateReader.java

@@ -149,12 +149,12 @@ public abstract class CoordinateReader
   protected abstract void readPointmap() throws Exception;
   
 
-  public static CoordinateReader obtainValidReader( String basedir, String segmentDir ) throws Exception
+  public static CoordinateReader obtainValidReader( String basedir, File segmentDir ) throws Exception
   {
     return obtainValidReader( basedir, segmentDir, false );
   }
 
-  public static CoordinateReader obtainValidReader( String basedir, String segmentDir, boolean nogosOnly ) throws Exception
+  public static CoordinateReader obtainValidReader( String basedir, File segmentDir, boolean nogosOnly ) throws Exception
   {
     CoordinateReader cor = null;
     ArrayList<CoordinateReader> rl = new ArrayList<CoordinateReader>();

brouter-server/src/main/java/btools/server/BRouter.java

@@ -6,6 +6,7 @@ import java.io.FileOutputStream;
 import java.net.URLDecoder;
 import java.util.ArrayList;
 import java.util.List;
+import java.io.File;
 
 import btools.router.OsmNodeNamed;
 import btools.router.RoutingContext;
@@ -75,7 +76,7 @@ public class BRouter
         wplist.add( from );
         wplist.add( to );
 
-        RoutingEngine re = new RoutingEngine( null, null, args[0], wplist, readRoutingContext(a2) );
+        RoutingEngine re = new RoutingEngine( null, null, new File (args[0]), wplist, readRoutingContext(a2) );
         re.doRun( maxRunningTime );
         if ( re.getErrorMessage() != null )
         {
@@ -111,7 +112,7 @@ public class BRouter
         SearchBoundary boundary = new SearchBoundary( wplist.get(0), searchRadius, direction/2 );
         rc.trafficOutputStream = dos;
         rc.inverseDirection = (direction & 1 ) != 0;
-        re = new RoutingEngine( "mytrack", "mylog", args[0], wplist, rc );
+        re = new RoutingEngine( "mytrack", "mylog", new File ( args[0] ), wplist, rc );
         re.boundary = boundary;
         re.airDistanceCostFactor = rc.trafficDirectionFactor;
         rc.countTraffic = true;
@@ -127,7 +128,7 @@ public class BRouter
     {
       wplist.add( readPosition( args, 3, "to" ) );
       RoutingContext rc = readRoutingContext(args);
-      re = new RoutingEngine( "mytrack", "mylog", args[0], wplist, rc );
+      re = new RoutingEngine( "mytrack", "mylog", new File ( args[0] ), wplist, rc );
       re.doRun( 0 );
       
     }

brouter-server/src/main/java/btools/server/RouteServer.java

@@ -294,7 +294,7 @@ public class RouteServer extends Thread implements Comparable<RouteServer>
         }
 
         ServiceContext serviceContext = new ServiceContext();
-        serviceContext.segmentDir = args[0];
+        serviceContext.segmentDir = new File ( args[0] );
         serviceContext.profileDir = args[1];
         System.setProperty( "profileBaseDir", serviceContext.profileDir );
         String dirs = args[2];

brouter-server/src/main/java/btools/server/ServiceContext.java

@@ -2,6 +2,7 @@ package btools.server;
 
 import java.util.List;
 import java.util.Map;
+import java.io.File;
 
 import btools.router.OsmNodeNamed;
 
@@ -10,7 +11,7 @@ import btools.router.OsmNodeNamed;
  */
 public class ServiceContext
 {
-  public String segmentDir;
+  public File segmentDir;
   public String profileDir;
   public String customProfileDir;
   public String sharedProfileDir;

brouter-server/src/test/java/btools/server/RouterTest.java

@@ -67,7 +67,7 @@ public class RouterTest
     RoutingEngine re = new RoutingEngine(
         wd + "/" + trackname,
         wd + "/" + trackname,
-        wd + "/../../../brouter-map-creator/target/test-classes/tmp/segments", wplist, rctx );
+        new File ( wd, "/../../../brouter-map-creator/target/test-classes/tmp/segments"), wplist, rctx );
     re.doRun( 0 );
     
     return re.getErrorMessage();