Pool dynamic

Reviewed By: ahmedre

Differential Revision: D4398446

fbshipit-source-id: ff528b7b52a2b1521627c0fca17b7ee2b18102de

ReactAndroid/src/main/java/com/facebook/react/bridge/DynamicFromArray.java

@@ -9,51 +9,92 @@
 
 package com.facebook.react.bridge;
 
+import javax.annotation.Nullable;
+
+import android.support.v4.util.Pools;
+
 /**
  * Implementation of Dynamic wrapping a ReadableArray.
  */
 public class DynamicFromArray implements Dynamic {
+  private static final Pools.SimplePool<DynamicFromArray> sPool = new Pools.SimplePool<>(10);
 
-  private final ReadableArray mArray;
-  private final int mIndex;
+  private @Nullable ReadableArray mArray;
+  private int mIndex = -1;
 
-  public DynamicFromArray(ReadableArray array, int index) {
-    mArray = array;
-    mIndex = index;
+  // This is a pools object. Hide the constructor.
+  private DynamicFromArray() {}
+
+  public static DynamicFromArray create(ReadableArray array, int index) {
+    DynamicFromArray dynamic = sPool.acquire();
+    if (dynamic == null) {
+      dynamic = new DynamicFromArray();
+    }
+    dynamic.mArray = array;
+    dynamic.mIndex = index;
+    return dynamic;
+  }
+
+  @Override
+  public void recycle() {
+    mArray = null;
+    mIndex = -1;
+    sPool.release(this);
   }
 
   @Override
   public boolean asBoolean() {
+    if (mArray == null) {
+      throw new IllegalStateException("This dynamic value has been recycled");
+    }
     return mArray.getBoolean(mIndex);
   }
 
   @Override
   public double asDouble() {
+    if (mArray == null) {
+      throw new IllegalStateException("This dynamic value has been recycled");
+    }
     return mArray.getDouble(mIndex);
   }
 
   @Override
   public int asInt() {
+    if (mArray == null) {
+      throw new IllegalStateException("This dynamic value has been recycled");
+    }
     return mArray.getInt(mIndex);
   }
 
   @Override
   public String asString() {
+    if (mArray == null) {
+      throw new IllegalStateException("This dynamic value has been recycled");
+    }
     return mArray.getString(mIndex);
   }
 
   @Override
   public ReadableArray asArray() {
+    if (mArray == null) {
+      throw new IllegalStateException("This dynamic value has been recycled");
+    }
     return mArray.getArray(mIndex);
   }
 
   @Override
   public ReadableMap asMap() {
+    if (mArray == null) {
+      throw new IllegalStateException("This dynamic value has been recycled");
+    }
     return mArray.getMap(mIndex);
   }
 
   @Override
   public ReadableType getType() {
+    if (mArray == null) {
+      throw new IllegalStateException("This dynamic value has been recycled");
+    }
     return mArray.getType(mIndex);
   }
 }