[android] - add binding integration for RasterDEMSource, add example

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/sources/RasterDemSource.java

@@ -0,0 +1,93 @@
+package com.mapbox.mapboxsdk.style.sources;
+
+import android.support.annotation.Nullable;
+import android.support.annotation.UiThread;
+
+import java.net.URL;
+
+/**
+ * A raster DEM source. Currently only supports Mapbox Terrain RGB (mapbox://mapbox.terrain-rgb)
+ *
+ * @see <a href="https://www.mapbox.com/mapbox-gl-js/style-spec/#sources-raster-dem">The style specification</a>
+ */
+@UiThread
+public class RasterDemSource extends Source {
+  public static final int DEFAULT_TILE_SIZE = 512;
+
+  /**
+   * Internal use
+   *
+   * @param nativePtr - pointer to native peer
+   */
+  private RasterDemSource(long nativePtr) {
+    super(nativePtr);
+  }
+
+  /**
+   * Create the raster dem source from an URL
+   *
+   * @param id  the source id
+   * @param url the source url
+   */
+  public RasterDemSource(String id, URL url) {
+    this(id, url.toExternalForm());
+  }
+
+  /**
+   * Create the raster dem source from an URL
+   *
+   * @param id  the source id
+   * @param url the source url
+   */
+  public RasterDemSource(String id, String url) {
+    initialize(id, url, DEFAULT_TILE_SIZE);
+  }
+
+  /**
+   * Create the raster source from an URL with a specific tile size
+   *
+   * @param id       the source id
+   * @param url      the source url
+   * @param tileSize the tile size
+   */
+  public RasterDemSource(String id, String url, int tileSize) {
+    initialize(id, url, tileSize);
+  }
+
+  /**
+   * Create the raster dem source from a {@link TileSet}
+   *
+   * @param id      the source id
+   * @param tileSet the {@link TileSet}
+   */
+  public RasterDemSource(String id, TileSet tileSet) {
+    initialize(id, tileSet.toValueObject(), DEFAULT_TILE_SIZE);
+  }
+
+  /**
+   * Create the raster source from a {@link TileSet} with a specific tile size
+   *
+   * @param id       the source id
+   * @param tileSet  the {@link TileSet}
+   * @param tileSize tje tile size
+   */
+  public RasterDemSource(String id, TileSet tileSet, int tileSize) {
+    initialize(id, tileSet.toValueObject(), tileSize);
+  }
+
+  /**
+   * @return The url or null
+   */
+  @Nullable
+  public String getUrl() {
+    return nativeGetUrl();
+  }
+
+  protected native void initialize(String layerId, Object payload, int tileSize);
+
+  @Override
+  protected native void finalize() throws Throwable;
+
+  protected native String nativeGetUrl();
+
+}