1 files changed, 38 insertions, 8 deletions

diff --git a/core/java/android/util/SparseArray.java b/core/java/android/util/SparseArray.java
index aa5ca3530621..0a15db227823 100644
--- a/core/java/android/util/SparseArray.java
+++ b/core/java/android/util/SparseArray.java
@@ -16,10 +16,11 @@
 
 package android.util;
 
+import android.annotation.UnsupportedAppUsage;
+
 import com.android.internal.util.ArrayUtils;
 import com.android.internal.util.GrowingArrayUtils;
 
-import android.annotation.UnsupportedAppUsage;
 import libcore.util.EmptyArray;
 
 /**
@@ -56,11 +57,11 @@ public class SparseArray<E> implements Cloneable {
     private static final Object DELETED = new Object();
     private boolean mGarbage = false;
 
-    @UnsupportedAppUsage
+    @UnsupportedAppUsage(maxTargetSdk = 28) // Use keyAt(int)
     private int[] mKeys;
-    @UnsupportedAppUsage
+    @UnsupportedAppUsage(maxTargetSdk = 28) // Use valueAt(int), setValueAt(int, E)
     private Object[] mValues;
-    @UnsupportedAppUsage
+    @UnsupportedAppUsage(maxTargetSdk = 28) // Use size()
     private int mSize;
 
     /**
@@ -168,9 +169,16 @@ public class SparseArray<E> implements Cloneable {
      * Removes the mapping at the specified index.
      *
      * <p>For indices outside of the range <code>0...size()-1</code>,
-     * the behavior is undefined.</p>
+     * the behavior is undefined for apps targeting {@link android.os.Build.VERSION_CODES#P} and
+     * earlier, and an {@link ArrayIndexOutOfBoundsException} is thrown for apps targeting
+     * {@link android.os.Build.VERSION_CODES#Q} and later.</p>
      */
     public void removeAt(int index) {
+        if (index >= mSize && UtilConfig.sThrowExceptionForUpperArrayOutOfBounds) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            // Check if exception should be thrown outside of the critical path.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
         if (mValues[index] != DELETED) {
             mValues[index] = DELETED;
             mGarbage = true;
@@ -276,9 +284,16 @@ public class SparseArray<E> implements Cloneable {
      * key.</p>
      *
      * <p>For indices outside of the range <code>0...size()-1</code>,
-     * the behavior is undefined.</p>
+     * the behavior is undefined for apps targeting {@link android.os.Build.VERSION_CODES#P} and
+     * earlier, and an {@link ArrayIndexOutOfBoundsException} is thrown for apps targeting
+     * {@link android.os.Build.VERSION_CODES#Q} and later.</p>
      */
     public int keyAt(int index) {
+        if (index >= mSize && UtilConfig.sThrowExceptionForUpperArrayOutOfBounds) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            // Check if exception should be thrown outside of the critical path.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
         if (mGarbage) {
             gc();
         }
@@ -298,10 +313,17 @@ public class SparseArray<E> implements Cloneable {
      * associated with the largest key.</p>
      *
      * <p>For indices outside of the range <code>0...size()-1</code>,
-     * the behavior is undefined.</p>
+     * the behavior is undefined for apps targeting {@link android.os.Build.VERSION_CODES#P} and
+     * earlier, and an {@link ArrayIndexOutOfBoundsException} is thrown for apps targeting
+     * {@link android.os.Build.VERSION_CODES#Q} and later.</p>
      */
     @SuppressWarnings("unchecked")
     public E valueAt(int index) {
+        if (index >= mSize && UtilConfig.sThrowExceptionForUpperArrayOutOfBounds) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            // Check if exception should be thrown outside of the critical path.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
         if (mGarbage) {
             gc();
         }
@@ -314,9 +336,17 @@ public class SparseArray<E> implements Cloneable {
      * value for the <code>index</code>th key-value mapping that this
      * SparseArray stores.
      *
-     * <p>For indices outside of the range <code>0...size()-1</code>, the behavior is undefined.</p>
+     * <p>For indices outside of the range <code>0...size()-1</code>, the behavior is undefined for
+     * apps targeting {@link android.os.Build.VERSION_CODES#P} and earlier, and an
+     * {@link ArrayIndexOutOfBoundsException} is thrown for apps targeting
+     * {@link android.os.Build.VERSION_CODES#Q} and later.</p>
      */
     public void setValueAt(int index, E value) {
+        if (index >= mSize && UtilConfig.sThrowExceptionForUpperArrayOutOfBounds) {
+            // The array might be slightly bigger than mSize, in which case, indexing won't fail.
+            // Check if exception should be thrown outside of the critical path.
+            throw new ArrayIndexOutOfBoundsException(index);
+        }
         if (mGarbage) {
             gc();
         }