Gating OutOfBoundsException on targetSdkVersion.

Apps targeting Pie or older will get the old undefined behavior. Apps
targeting Q or newer will get the OutOfBoundsException.

Bug: 118339123
Test: atest CtsUtilTestCases
Change-Id: Ibf5467aadec4a2f76ee180e963afeaf5a8a013a2

1 files changed, 14 insertions, 2 deletions

diff --git a/core/java/android/util/ArraySet.java b/core/java/android/util/ArraySet.java
index 4bd43d05ae61..610641d6f962 100644
--- a/core/java/android/util/ArraySet.java
+++ b/core/java/android/util/ArraySet.java
@@ -356,11 +356,17 @@ public final class ArraySet<E> implements Collection<E>, Set<E> {
 
     /**
      * Return the value at the given index in the array.
+     *
+     * <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>
+     *
      * @param index The desired index, must be between 0 and {@link #size()}-1.
      * @return Returns the value stored at the given index.
      */
     public E valueAt(int index) {
-        if (index >= mSize) {
+        if (index >= mSize && UtilConfig.sThrowExceptionForUpperArrayOutOfBounds) {
             // The array might be slightly bigger than mSize, in which case, indexing won't fail.
             throw new ArrayIndexOutOfBoundsException(index);
         }
@@ -527,11 +533,17 @@ public final class ArraySet<E> implements Collection<E>, Set<E> {
 
     /**
      * Remove the key/value mapping at the given index.
+     *
+     * <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>
+     *
      * @param index The desired index, must be between 0 and {@link #size()}-1.
      * @return Returns the value that was stored at this index.
      */
     public E removeAt(int index) {
-        if (index >= mSize) {
+        if (index >= mSize && UtilConfig.sThrowExceptionForUpperArrayOutOfBounds) {
             // The array might be slightly bigger than mSize, in which case, indexing won't fail.
             throw new ArrayIndexOutOfBoundsException(index);
         }