diff --git a/core/java/android/content/res/ApkAssets.java b/core/java/android/content/res/ApkAssets.java
index f3783e4..224ff14c 100644
--- a/core/java/android/content/res/ApkAssets.java
+++ b/core/java/android/content/res/ApkAssets.java
@@ -334,13 +334,14 @@
         }
     }
 
+    @Nullable
     CharSequence getStringFromPool(int idx) {
         if (mStringBlock == null) {
             return null;
         }
 
         synchronized (this) {
-            return mStringBlock.get(idx);
+            return mStringBlock.getSequence(idx);
         }
     }
 
diff --git a/core/java/android/content/res/AssetManager.java b/core/java/android/content/res/AssetManager.java
index 13433dc..d50404e 100644
--- a/core/java/android/content/res/AssetManager.java
+++ b/core/java/android/content/res/AssetManager.java
@@ -550,7 +550,9 @@
                     outValue.changingConfigurations);
 
             if (outValue.type == TypedValue.TYPE_STRING) {
-                outValue.string = getPooledStringForCookie(cookie, outValue.data);
+                if ((outValue.string = getPooledStringForCookie(cookie, outValue.data)) == null) {
+                    return false;
+                }
             }
             return true;
         }
@@ -731,7 +733,9 @@
                     outValue.changingConfigurations);
 
             if (outValue.type == TypedValue.TYPE_STRING) {
-                outValue.string = getPooledStringForCookie(cookie, outValue.data);
+                if ((outValue.string = getPooledStringForCookie(cookie, outValue.data)) == null) {
+                    return false;
+                }
             }
             return true;
         }
@@ -833,6 +837,7 @@
         }
     }
 
+    @Nullable
     CharSequence getPooledStringForCookie(int cookie, int id) {
         // Cookies map to ApkAssets starting at 1.
         return getApkAssets()[cookie - 1].getStringFromPool(id);
diff --git a/core/java/android/content/res/StringBlock.java b/core/java/android/content/res/StringBlock.java
index 8f3f77b..5bc235f 100644
--- a/core/java/android/content/res/StringBlock.java
+++ b/core/java/android/content/res/StringBlock.java
@@ -16,6 +16,8 @@
 
 package android.content.res;
 
+import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.graphics.Color;
 import android.graphics.Paint;
@@ -86,8 +88,19 @@
                 + ": " + nativeGetSize(mNative));
     }
 
+    /**
+     * @deprecated use {@link #getSequence(int)} which can return null when a string cannot be found
+     *             due to incremental installation.
+     */
+    @Deprecated
     @UnsupportedAppUsage
     public CharSequence get(int idx) {
+        CharSequence seq = getSequence(idx);
+        return seq == null ? "" : seq;
+    }
+
+    @Nullable
+    public CharSequence getSequence(int idx) {
         synchronized (this) {
             if (mStrings != null) {
                 CharSequence res = mStrings[idx];
@@ -108,6 +121,9 @@
                 }
             }
             String str = nativeGetString(mNative, idx);
+            if (str == null) {
+                return null;
+            }
             CharSequence res = str;
             int[] style = nativeGetStyle(mNative, idx);
             if (localLOGV) Log.v(TAG, "Got string: " + str);
@@ -133,6 +149,9 @@
                     }
 
                     String styleTag = nativeGetString(mNative, styleId);
+                    if (styleTag == null) {
+                        return null;
+                    }
 
                     if (styleTag.equals("b")) {
                         mStyleIDs.boldId = styleId;
@@ -161,8 +180,10 @@
 
                 res = applyStyles(str, style, mStyleIDs);
             }
-            if (mStrings != null) mStrings[idx] = res;
-            else mSparseStrings.put(idx, res);
+            if (res != null) {
+                if (mStrings != null) mStrings[idx] = res;
+                else mSparseStrings.put(idx, res);
+            }
             return res;
         }
     }
@@ -203,6 +224,7 @@
         private int marqueeId = -1;
     }
 
+    @Nullable
     private CharSequence applyStyles(String str, int[] style, StyleIDs ids) {
         if (style.length == 0)
             return str;
@@ -260,6 +282,9 @@
                                Spannable.SPAN_INCLUSIVE_INCLUSIVE);
             } else {
                 String tag = nativeGetString(mNative, type);
+                if (tag == null) {
+                    return null;
+                }
 
                 if (tag.startsWith("font;")) {
                     String sub;
diff --git a/core/java/android/content/res/TypedArray.java b/core/java/android/content/res/TypedArray.java
index 2a349e9..d6f55d6 100644
--- a/core/java/android/content/res/TypedArray.java
+++ b/core/java/android/content/res/TypedArray.java
@@ -1376,6 +1376,7 @@
         return true;
     }
 
+    @Nullable
     private CharSequence loadStringValueAt(int index) {
         final int[] data = mData;
         final int cookie = data[index + STYLE_ASSET_COOKIE];
diff --git a/core/java/android/content/res/XmlBlock.java b/core/java/android/content/res/XmlBlock.java
index b0291ce..53dfed3 100644
--- a/core/java/android/content/res/XmlBlock.java
+++ b/core/java/android/content/res/XmlBlock.java
@@ -19,6 +19,7 @@
 import static android.content.res.Resources.ID_NULL;
 
 import android.annotation.AnyRes;
+import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.os.Build;
@@ -161,9 +162,10 @@
         public int getDepth() {
             return mDepth;
         }
+        @Nullable
         public String getText() {
             int id = nativeGetText(mParseState);
-            return id >= 0 ? mStrings.get(id).toString() : null;
+            return id >= 0 ? getSequenceString(mStrings.getSequence(id)) : null;
         }
         public int getLineNumber() {
             return nativeGetLineNumber(mParseState);
@@ -189,25 +191,29 @@
             }
             return chars;
         }
+        @Nullable
         public String getNamespace() {
             int id = nativeGetNamespace(mParseState);
-            return id >= 0 ? mStrings.get(id).toString() : "";
+            return id >= 0 ? getSequenceString(mStrings.getSequence(id)) : "";
         }
+        @Nullable
         public String getName() {
             int id = nativeGetName(mParseState);
-            return id >= 0 ? mStrings.get(id).toString() : null;
+            return id >= 0 ? getSequenceString(mStrings.getSequence(id)) : null;
         }
+        @NonNull
         public String getAttributeNamespace(int index) {
             int id = nativeGetAttributeNamespace(mParseState, index);
             if (DEBUG) System.out.println("getAttributeNamespace of " + index + " = " + id);
-            if (id >= 0) return mStrings.get(id).toString();
+            if (id >= 0) return getSequenceString(mStrings.getSequence(id));
             else if (id == -1) return "";
             throw new IndexOutOfBoundsException(String.valueOf(index));
         }
+        @NonNull
         public String getAttributeName(int index) {
             int id = nativeGetAttributeName(mParseState, index);
             if (DEBUG) System.out.println("getAttributeName of " + index + " = " + id);
-            if (id >= 0) return mStrings.get(id).toString();
+            if (id >= 0) return getSequenceString(mStrings.getSequence(id));
             throw new IndexOutOfBoundsException(String.valueOf(index));
         }
         public String getAttributePrefix(int index) {
@@ -220,10 +226,11 @@
         public int getAttributeCount() {
             return mEventType == START_TAG ? nativeGetAttributeCount(mParseState) : -1;
         }
+        @NonNull
         public String getAttributeValue(int index) {
             int id = nativeGetAttributeStringValue(mParseState, index);
             if (DEBUG) System.out.println("getAttributeValue of " + index + " = " + id);
-            if (id >= 0) return mStrings.get(id).toString();
+            if (id >= 0) return getSequenceString(mStrings.getSequence(id));
 
             // May be some other type...  check and try to convert if so.
             int t = nativeGetAttributeDataType(mParseState, index);
@@ -390,7 +397,7 @@
             int v = nativeGetAttributeData(mParseState, idx);
             if (t == TypedValue.TYPE_STRING) {
                 return XmlUtils.convertValueToList(
-                    mStrings.get(v), options, defaultValue);
+                    mStrings.getSequence(v), options, defaultValue);
             }
             return v;
         }
@@ -444,14 +451,15 @@
             }
             throw new RuntimeException("not a float!");
         }
-
+        @Nullable
         public String getIdAttribute() {
             int id = nativeGetIdAttribute(mParseState);
-            return id >= 0 ? mStrings.get(id).toString() : null;
+            return id >= 0 ? getSequenceString(mStrings.getSequence(id)) : null;
         }
+        @Nullable
         public String getClassAttribute() {
             int id = nativeGetClassAttribute(mParseState);
-            return id >= 0 ? mStrings.get(id).toString() : null;
+            return id >= 0 ? getSequenceString(mStrings.getSequence(id)) : null;
         }
 
         public int getIdAttributeResourceValue(int defaultValue) {
@@ -463,6 +471,17 @@
             return nativeGetStyleAttribute(mParseState);
         }
 
+        private String getSequenceString(@Nullable CharSequence str) {
+            if (str == null) {
+                // A value of null retrieved from a StringPool indicates that retrieval of the
+                // string failed due to incremental installation. The presence of all the XmlBlock
+                // data is verified when it is created, so this exception must not be possible.
+                throw new IllegalStateException("Retrieving a string from the StringPool of an"
+                        + " XmlBlock should never fail");
+            }
+            return str.toString();
+        }
+
         public void close() {
             synchronized (mBlock) {
                 if (mParseState != 0) {
@@ -472,13 +491,14 @@
                 }
             }
         }
-        
+
         protected void finalize() throws Throwable {
             close();
         }
 
+        @Nullable
         /*package*/ final CharSequence getPooledString(int id) {
-            return mStrings.get(id);
+            return mStrings.getSequence(id);
         }
 
         @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
diff --git a/core/jni/android_util_StringBlock.cpp b/core/jni/android_util_StringBlock.cpp
index d94e084..dd7df26 100644
--- a/core/jni/android_util_StringBlock.cpp
+++ b/core/jni/android_util_StringBlock.cpp
@@ -72,7 +72,7 @@
     ResStringPool* osb = reinterpret_cast<ResStringPool*>(token);
     if (osb == NULL) {
         jniThrowNullPointerException(env, NULL);
-        return 0;
+        return NULL;
     }
 
     if (auto str8 = osb->string8At(idx); str8.has_value()) {
@@ -80,9 +80,11 @@
     }
 
     auto str = osb->stringAt(idx);
-    if (UNLIKELY(!str.has_value())) {
+    if (IsIOError(str)) {
+        return NULL;
+    } else if (UNLIKELY(!str.has_value())) {
         jniThrowException(env, "java/lang/IndexOutOfBoundsException", NULL);
-        return 0;
+        return NULL;
     }
 
     return env->NewString((const jchar*)str->data(), str->size());