1 files changed, 19 insertions, 2 deletions

diff --git a/core/java/android/util/ArrayMap.java b/core/java/android/util/ArrayMap.java
index 436cb4ff7072..e2af6f5ed102 100644
--- a/core/java/android/util/ArrayMap.java
+++ b/core/java/android/util/ArrayMap.java
@@ -16,12 +16,12 @@
 
 package android.util;
 
-import libcore.util.EmptyArray;
-
 import android.annotation.UnsupportedAppUsage;
 
 import com.android.internal.util.ArrayUtils;
 
+import libcore.util.EmptyArray;
+
 import java.util.Collection;
 import java.util.ConcurrentModificationException;
 import java.util.Map;
@@ -453,6 +453,10 @@ public final class ArrayMap<K, V> implements Map<K, V> {
      * @return Returns the key stored at the given index.
      */
     public K keyAt(int index) {
+        if (index >= mSize) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
         return (K)mArray[index << 1];
     }
 
@@ -462,6 +466,10 @@ public final class ArrayMap<K, V> implements Map<K, V> {
      * @return Returns the value stored at the given index.
      */
     public V valueAt(int index) {
+        if (index >= mSize) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
         return (V)mArray[(index << 1) + 1];
     }
 
@@ -472,6 +480,10 @@ public final class ArrayMap<K, V> implements Map<K, V> {
      * @return Returns the previous value at the given index.
      */
     public V setValueAt(int index, V value) {
+        if (index >= mSize) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
         index = (index << 1) + 1;
         V old = (V)mArray[index];
         mArray[index] = value;
@@ -665,6 +677,11 @@ public final class ArrayMap<K, V> implements Map<K, V> {
      * @return Returns the value that was stored at this index.
      */
     public V removeAt(int index) {
+        if (index >= mSize) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
+
         final Object old = mArray[(index << 1) + 1];
         final int osize = mSize;
         final int nsize;