load country boundaries asynchronously, only block main thread when t…

…he boundaries are needed now but loading is not complete yet (#416)
streetcomplete · Jul 26, 2017 · f0e80f9 · f0e80f9
1 parent b185135
commit f0e80f9
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Showing 4 changed files with 62 additions and 59 deletions.
diff --git a/app/src/androidTest/java/de/westnordost/streetcomplete/data/meta/CountryBoundariesTest.java b/app/src/androidTest/java/de/westnordost/streetcomplete/data/meta/CountryBoundariesTest.java
@@ -1,9 +1,9 @@
 package de.westnordost.streetcomplete.data.meta;
 
+import com.vividsolutions.jts.geom.GeometryCollection;
+
 import junit.framework.TestCase;
 
-import java.io.ByteArrayInputStream;
-import java.io.UnsupportedEncodingException;
 import java.util.Arrays;
 import java.util.Collections;
 
@@ -25,14 +25,8 @@ public class CountryBoundariesTest extends TestCase
 
 	public void setUp()
 	{
-		try
-		{
-			countryBoundaries = new CountryBoundaries(new ByteArrayInputStream(testGeoJson.getBytes("UTF-8")));
-		}
-		catch (UnsupportedEncodingException e)
-		{
-			throw new RuntimeException(e);
-		}
+		countryBoundaries = new CountryBoundaries(
+				(GeometryCollection) new GeoJsonReader().read(testGeoJson));
 	}
 
 	public void testIsIn()

diff --git a/app/src/main/java/de/westnordost/streetcomplete/data/meta/CountryBoundaries.java b/app/src/main/java/de/westnordost/streetcomplete/data/meta/CountryBoundaries.java
@@ -10,9 +10,6 @@
 import com.vividsolutions.jts.index.SpatialIndex;
 import com.vividsolutions.jts.index.strtree.STRtree;
 
-import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -34,14 +31,13 @@ public class CountryBoundaries
 	private final Map<String, Geometry> geometriesByIsoCodes;
 	private final Map<Geometry, Double> geometrySizeCache;
 
-	public CountryBoundaries(InputStream is)
+	public CountryBoundaries(GeometryCollection countriesBoundaries)
 	{
 		long time = System.currentTimeMillis();
 		index = new STRtree();
 		geometrySizeCache = new HashMap<>(400);
 		geometriesByIsoCodes = new HashMap<>(400);
 
-		GeometryCollection countriesBoundaries = (GeometryCollection) load(is);
 		for(int i = 0; i < countriesBoundaries.getNumGeometries(); ++i)
 		{
 			Geometry countryBoundary = countriesBoundaries.getGeometryN(i);
@@ -151,39 +147,4 @@ else if(props.containsKey(ISO3166_2))
 		}
 		return result;
 	}
-
-	private String readToString(InputStream is) throws IOException
-	{
-		try
-		{
-			ByteArrayOutputStream result = new ByteArrayOutputStream();
-			byte[] buffer = new byte[1024];
-			int length;
-			while ((length = is.read(buffer)) != -1)
-			{
-				result.write(buffer, 0, length);
-			}
-			return result.toString("UTF-8");
-		}
-		finally
-		{
-			if(is != null) try
-			{
-				is.close();
-			}
-			catch (IOException e) { }
-		}
-	}
-
-	private Geometry load(InputStream is)
-	{
-		try
-		{
-			return new GeoJsonReader().read(readToString(is));
-		}
-		catch (IOException e)
-		{
-			throw new RuntimeException(e);
-		}
-	}
 }
diff --git a/app/src/main/java/de/westnordost/streetcomplete/data/meta/CountryInfos.java b/app/src/main/java/de/westnordost/streetcomplete/data/meta/CountryInfos.java
@@ -14,6 +14,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.Future;
 
 import javax.inject.Inject;
 
@@ -22,13 +23,13 @@ public class CountryInfos
 	private static final String BASEPATH = "country_metadata";
 
 	private final AssetManager assetManager;
-	private final CountryBoundaries countryBoundaries;
+	private final Future<CountryBoundaries> countryBoundaries;
 
 	private CountryInfo defaultCountryInfo;
 
 	private Map<String, CountryInfo> countryInfoMap;
 
-	@Inject public CountryInfos(AssetManager assetManager, CountryBoundaries countryBoundaries)
+	@Inject public CountryInfos(AssetManager assetManager, Future<CountryBoundaries> countryBoundaries)
 	{
 		this.assetManager = assetManager;
 		this.countryBoundaries = countryBoundaries;
@@ -38,8 +39,15 @@ public class CountryInfos
 	/** Get the info by location */
 	public CountryInfo get(double longitude, double latitude)
 	{
-		List<String> countryCodesIso3166 = countryBoundaries.getIsoCodes(longitude, latitude);
-		return get(countryCodesIso3166);
+		try
+		{
+			List<String> countryCodesIso3166 = countryBoundaries.get().getIsoCodes(longitude, latitude);
+			return get(countryCodesIso3166);
+		}
+		catch (Exception e)
+		{
+			throw new RuntimeException(e);
+		}
 	}
 
 	/** Get the info by a list of country codes sorted by size. I.e. DE-NI,DE,EU gets the info

diff --git a/app/src/main/java/de/westnordost/streetcomplete/data/meta/MetadataModule.java b/app/src/main/java/de/westnordost/streetcomplete/data/meta/MetadataModule.java
@@ -2,7 +2,14 @@
 
 import android.content.res.AssetManager;
 
+import com.vividsolutions.jts.geom.GeometryCollection;
+
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
+import java.util.concurrent.Callable;
+import java.util.concurrent.Future;
+import java.util.concurrent.FutureTask;
 
 import javax.inject.Singleton;
 
@@ -13,20 +20,53 @@
 public class MetadataModule
 {
 	@Provides @Singleton public static CountryInfos countryInfos(
-			AssetManager assetManager, CountryBoundaries countryBoundaries)
+			AssetManager assetManager, Future<CountryBoundaries> countryBoundaries)
 	{
 		return new CountryInfos(assetManager, countryBoundaries);
 	}
 
-	@Provides @Singleton public static CountryBoundaries countryBoundaries(AssetManager assetManager)
+	@Provides public static GeoJsonReader geoJsonReader()
+	{
+		return new GeoJsonReader();
+	}
+
+	@Provides @Singleton public static Future<CountryBoundaries> countryBoundariesFuture(
+			final AssetManager assetManager, final GeoJsonReader geoJsonReader)
+	{
+		FutureTask<CountryBoundaries> ft = new FutureTask<>(new Callable<CountryBoundaries>()
+		{
+			@Override public CountryBoundaries call() throws Exception
+			{
+				InputStream is = assetManager.open("countryBoundaries.json");
+				return new CountryBoundaries(
+						(GeometryCollection) geoJsonReader.read(readToString(is)));
+			}
+		});
+		// start creating (=loading) CountryBoundaries asynchronously
+		new Thread(ft).start();
+		return ft;
+	}
+
+	private static String readToString(InputStream is) throws IOException
 	{
 		try
 		{
-			return new CountryBoundaries(assetManager.open("countryBoundaries.json"));
+			ByteArrayOutputStream result = new ByteArrayOutputStream();
+			byte[] buffer = new byte[1024];
+			int length;
+			while ((length = is.read(buffer)) != -1)
+			{
+				result.write(buffer, 0, length);
+			}
+			return result.toString("UTF-8");
 		}
-		catch (IOException e)
+		finally
 		{
-			throw new RuntimeException(e);
+			if(is != null) try
+			{
+				is.close();
+			}
+			catch (IOException e) { }
 		}
 	}
 }