diff --git a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillExtrusionLayerTest.java b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillExtrusionLayerTest.java
index cdfd030f9..4b936a4c9 100644
--- a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillExtrusionLayerTest.java
+++ b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillExtrusionLayerTest.java
@@ -244,7 +244,7 @@ public class FillExtrusionLayerTest extends BaseLayerTest {
     assertNull(layer.getFillExtrusionPattern().getExpression());
 
     // Set and Get
-    Expression expression = string(Expression.get("undefined"));
+    Expression expression = image(string(Expression.get("undefined")));
     layer.setProperties(fillExtrusionPattern(expression));
     assertEquals(layer.getFillExtrusionPattern().getExpression(), expression);
   }
diff --git a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillLayerTest.java b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillLayerTest.java
index f6e3cc854..4e9dddc0a 100644
--- a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillLayerTest.java
+++ b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/FillLayerTest.java
@@ -319,7 +319,7 @@ public class FillLayerTest extends BaseLayerTest {
     assertNull(layer.getFillPattern().getExpression());
 
     // Set and Get
-    Expression expression = string(Expression.get("undefined"));
+    Expression expression = image(string(Expression.get("undefined")));
     layer.setProperties(fillPattern(expression));
     assertEquals(layer.getFillPattern().getExpression(), expression);
   }
diff --git a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/LineLayerTest.java b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/LineLayerTest.java
index 5e00890f7..4c8e70d3d 100644
--- a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/LineLayerTest.java
+++ b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/LineLayerTest.java
@@ -486,7 +486,7 @@ public class LineLayerTest extends BaseLayerTest {
     assertNull(layer.getLinePattern().getExpression());
 
     // Set and Get
-    Expression expression = string(Expression.get("undefined"));
+    Expression expression = image(string(Expression.get("undefined")));
     layer.setProperties(linePattern(expression));
     assertEquals(layer.getLinePattern().getExpression(), expression);
   }
diff --git a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/SymbolLayerTest.java b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/SymbolLayerTest.java
index c65e37019..02205b3c9 100644
--- a/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/SymbolLayerTest.java
+++ b/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/SymbolLayerTest.java
@@ -296,7 +296,7 @@ public class SymbolLayerTest extends BaseLayerTest {
     assertEquals(layer.getIconImage().getValue(), propertyValue);
 
     layer.setProperties(iconImage("{token}"));
-    assertEquals(layer.getIconImage().getExpression(), Expression.toString(Expression.get("token")));
+    assertEquals(layer.getIconImage().getExpression(), image(Expression.toString(Expression.get("token"))));
   }
 
   @Test
@@ -307,7 +307,7 @@ public class SymbolLayerTest extends BaseLayerTest {
     assertNull(layer.getIconImage().getExpression());
 
     // Set and Get
-    Expression expression = string(Expression.get("undefined"));
+    Expression expression = image(string(Expression.get("undefined")));
     layer.setProperties(iconImage(expression));
     assertEquals(layer.getIconImage().getExpression(), expression);
   }
diff --git a/scripts/generate-style-code.js b/scripts/generate-style-code.js
index ea68a059d..fd9490445 100755
--- a/scripts/generate-style-code.js
+++ b/scripts/generate-style-code.js
@@ -374,15 +374,11 @@ const lightJavaUnitTests = ejs.compile(fs.readFileSync('MapboxGLAndroidSDKTestAp
 writeIfModified(`MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/light/Light.java`, lightJava({properties: lightProperties}));
 writeIfModified(`MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/LightTest.java`, lightJavaUnitTests({properties: lightProperties}));
 
-// Java + JNI Layers (Peer model)
-const layerHpp = ejs.compile(fs.readFileSync('src/style/layers/layer.hpp.ejs', 'utf8'), {strict: true});
-const layerCpp = ejs.compile(fs.readFileSync('src/style/layers/layer.cpp.ejs', 'utf8'), {strict: true});
+// Java
 const layerJava = ejs.compile(fs.readFileSync('MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/layer.java.ejs', 'utf8'), {strict: true});
 const layerJavaUnitTests = ejs.compile(fs.readFileSync('MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/layer.junit.ejs', 'utf8'), {strict: true});
 
 for (const layer of layers) {
-  writeIfModified(`src/style/layers/${layer.type.replace('-', '_')}_layer.hpp`, layerHpp(layer));
-  writeIfModified(`src/style/layers/${layer.type.replace('-', '_')}_layer.cpp`, layerCpp(layer));
   writeIfModified(`MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/${camelize(layer.type)}Layer.java`, layerJava(layer));
   writeIfModified(`MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/${camelize(layer.type)}LayerTest.java`, layerJavaUnitTests(layer));
 }