Optimize getHashMapFromPropsReadableMap in SurfaceMountingManager (facebook#54358)

Summary:
Pull Request resolved: facebook#54358

Improved the performance of getHashMapFromPropsReadableMap by replacing the iterator-based approach with direct key lookups. The function now directly checks for "transform" and "opacity" keys using hasKey() and getType() instead of iterating through all entries in the ReadableMap.

This optimization reduces the time complexity from O(n) to O(1) for the two specific keys we need, eliminating unnecessary iterations through irrelevant entries. Additionally, the ArrayList for transform is now pre-sized with the correct capacity to avoid reallocations.

Changelog: [Internal]

Reviewed By: christophpurrer

Differential Revision: D85967272

fbshipit-source-id: 7da60aa6383dd8b5b830f201d5bc66c7ab984572

Author: Nick Lefever

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/SurfaceMountingManager.java

@@ -60,7 +60,6 @@
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.Iterator;
 import java.util.LinkedList;
 import java.util.Map;
 import java.util.Queue;
@@ -71,6 +70,8 @@ public class SurfaceMountingManager {
   public static final String TAG = SurfaceMountingManager.class.getSimpleName();
 
   private static final boolean SHOW_CHANGED_VIEW_HIERARCHIES = ReactBuildConfig.DEBUG && false;
+  private static final String PROP_TRANSFORM = "transform";
+  private static final String PROP_OPACITY = "opacity";
 
   private volatile boolean mIsStopped = false;
   private volatile boolean mRootViewAttached = false;
@@ -700,7 +701,7 @@ private static void overridePropsReadableMap(
       String propKey = entry.getKey();
       if (outputReadableMap.hasKey(propKey)) {
         Object propValue = entry.getValue();
-        if (propKey.equals("transform")) {
+        if (propKey.equals(PROP_TRANSFORM)) {
           assert (outputReadableMap.getType(propKey) == ReadableType.Array
               && propValue instanceof ArrayList);
           WritableArray array = new WritableNativeArray();
@@ -720,7 +721,7 @@ private static void overridePropsReadableMap(
             }
           }
           outputReadableMap.putArray(propKey, array);
-        } else if (propKey.equals("opacity")) {
+        } else if (propKey.equals(PROP_OPACITY)) {
           assert (outputReadableMap.getType(propKey) == ReadableType.Number
               && propValue instanceof Number);
           outputReadableMap.putDouble(propKey, ((Number) propValue).doubleValue());
@@ -732,25 +733,26 @@ private static void overridePropsReadableMap(
   private static Map<String, Object> getHashMapFromPropsReadableMap(ReadableMap readableMap) {
     HashMap<String, Object> outputMap = new HashMap<>();
 
-    Iterator<Map.Entry<String, Object>> iter = readableMap.getEntryIterator();
-    while (iter.hasNext()) {
-      Map.Entry<String, Object> entry = iter.next();
-      String propKey = entry.getKey();
-      Object propValue = entry.getValue();
-      if (propKey.equals("transform") && propValue instanceof ReadableArray) {
-        ArrayList<HashMap<String, Object>> arrayList = new ArrayList<>();
-        for (int i = 0; i < ((ReadableArray) propValue).size(); i++) {
-          ReadableMap map = ((ReadableArray) propValue).getMap(i);
+    if (readableMap.hasKey(PROP_TRANSFORM)
+        && readableMap.getType(PROP_TRANSFORM) == ReadableType.Array) {
+      ReadableArray transformArray = readableMap.getArray(PROP_TRANSFORM);
+      if (transformArray != null) {
+        ArrayList<HashMap<String, Object>> arrayList = new ArrayList<>(transformArray.size());
+        for (int i = 0; i < transformArray.size(); i++) {
+          ReadableMap map = transformArray.getMap(i);
           if (map != null) {
             arrayList.add(map.toHashMap());
           }
         }
-        outputMap.put(propKey, arrayList);
-      } else if (propKey.equals("opacity") && propValue instanceof Number) {
-        outputMap.put(propKey, ((Number) propValue).doubleValue());
+        outputMap.put(PROP_TRANSFORM, arrayList);
       }
     }
 
+    if (readableMap.hasKey(PROP_OPACITY)
+        && readableMap.getType(PROP_OPACITY) == ReadableType.Number) {
+      outputMap.put(PROP_OPACITY, readableMap.getDouble(PROP_OPACITY));
+    }
+
     return outputMap;
   }