1 files changed, 22 insertions, 17 deletions

diff --git a/core/java/android/util/ArrayMap.java b/core/java/android/util/ArrayMap.java
index bdb1fdcb9ff8..92a5803b5ddb 100644
--- a/core/java/android/util/ArrayMap.java
+++ b/core/java/android/util/ArrayMap.java
@@ -67,7 +67,7 @@ public final class ArrayMap<K, V> implements Map<K, V> {
     /**
      * @hide Special immutable empty ArrayMap.
      */
-    public static final ArrayMap EMPTY = new ArrayMap(true);
+    public static final ArrayMap EMPTY = new ArrayMap<>(-1);
 
     /**
      * Caches of small array objects to avoid spamming garbage.  The cache
@@ -80,6 +80,7 @@ public final class ArrayMap<K, V> implements Map<K, V> {
     static Object[] mTwiceBaseCache;
     static int mTwiceBaseCacheSize;
 
+    final boolean mIdentityHashCode;
     int[] mHashes;
     Object[] mArray;
     int mSize;
@@ -236,30 +237,32 @@ public final class ArrayMap<K, V> implements Map<K, V> {
      * will grow once items are added to it.
      */
     public ArrayMap() {
-        mHashes = EmptyArray.INT;
-        mArray = EmptyArray.OBJECT;
-        mSize = 0;
+        this(0, false);
     }
 
     /**
      * Create a new ArrayMap with a given initial capacity.
      */
     public ArrayMap(int capacity) {
-        if (capacity == 0) {
-            mHashes = EmptyArray.INT;
-            mArray = EmptyArray.OBJECT;
-        } else {
-            allocArrays(capacity);
-        }
-        mSize = 0;
+        this(capacity, false);
     }
 
-    private ArrayMap(boolean immutable) {
+    /** {@hide} */
+    public ArrayMap(int capacity, boolean identityHashCode) {
+        mIdentityHashCode = identityHashCode;
+
         // If this is immutable, use the sentinal EMPTY_IMMUTABLE_INTS
         // instance instead of the usual EmptyArray.INT. The reference
         // is checked later to see if the array is allowed to grow.
-        mHashes = immutable ? EMPTY_IMMUTABLE_INTS : EmptyArray.INT;
-        mArray = EmptyArray.OBJECT;
+        if (capacity < 0) {
+            mHashes = EMPTY_IMMUTABLE_INTS;
+            mArray = EmptyArray.OBJECT;
+        } else if (capacity == 0) {
+            mHashes = EmptyArray.INT;
+            mArray = EmptyArray.OBJECT;
+        } else {
+            allocArrays(capacity);
+        }
         mSize = 0;
     }
 
@@ -336,7 +339,8 @@ public final class ArrayMap<K, V> implements Map<K, V> {
      * @return Returns the index of the key if it exists, else a negative integer.
      */
     public int indexOfKey(Object key) {
-        return key == null ? indexOfNull() : indexOf(key, key.hashCode());
+        return key == null ? indexOfNull()
+                : indexOf(key, mIdentityHashCode ? System.identityHashCode(key) : key.hashCode());
     }
 
     int indexOfValue(Object value) {
@@ -437,7 +441,7 @@ public final class ArrayMap<K, V> implements Map<K, V> {
             hash = 0;
             index = indexOfNull();
         } else {
-            hash = key.hashCode();
+            hash = mIdentityHashCode ? System.identityHashCode(key) : key.hashCode();
             index = indexOf(key, hash);
         }
         if (index >= 0) {
@@ -488,7 +492,8 @@ public final class ArrayMap<K, V> implements Map<K, V> {
      */
     public void append(K key, V value) {
         int index = mSize;
-        final int hash = key == null ? 0 : key.hashCode();
+        final int hash = key == null ? 0
+                : (mIdentityHashCode ? System.identityHashCode(key) : key.hashCode());
         if (index >= mHashes.length) {
             throw new IllegalStateException("Array is full");
         }