diff --git a/src/java.base/share/classes/java/io/ObjectInput.java b/src/java.base/share/classes/java/io/ObjectInput.java
index d13301ba472..4f6bf226f42 100644
--- a/src/java.base/share/classes/java/io/ObjectInput.java
+++ b/src/java.base/share/classes/java/io/ObjectInput.java
@@ -51,7 +51,7 @@ public interface ObjectInput extends DataInput, AutoCloseable {
      * @exception IOException If any of the usual Input/Output
      * related exceptions occur.
      */
-    public Object readObject()
+    public @Nullable Object readObject()
         throws ClassNotFoundException, IOException;
 
     /**
diff --git a/src/java.base/share/classes/java/io/ObjectInputStream.java b/src/java.base/share/classes/java/io/ObjectInputStream.java
index 912c3123b2c..3eb2f2e8273 100644
--- a/src/java.base/share/classes/java/io/ObjectInputStream.java
+++ b/src/java.base/share/classes/java/io/ObjectInputStream.java
@@ -421,7 +421,7 @@ protected ObjectInputStream() throws IOException, SecurityException {
      *          stream instead of objects.
      * @throws  IOException Any of the usual Input/Output related exceptions.
      */
-    public final Object readObject()
+    public final @Nullable Object readObject()
         throws IOException, ClassNotFoundException
     {
         if (enableOverride) {
@@ -467,7 +467,7 @@ public final Object readObject()
      * @see #readObject()
      * @since 1.2
      */
-    protected Object readObjectOverride()
+    protected @Nullable Object readObjectOverride()
         throws IOException, ClassNotFoundException
     {
         return null;
@@ -522,7 +522,7 @@ protected Object readObjectOverride()
      * @throws  IOException if an I/O error occurs during deserialization
      * @since   1.4
      */
-    public Object readUnshared() throws IOException, ClassNotFoundException {
+    public @Nullable Object readUnshared() throws IOException, ClassNotFoundException {
         // if nested read, passHandle contains handle of enclosing object
         int outerHandle = passHandle;
         try {
@@ -1167,7 +1167,7 @@ public String readUTF() throws IOException {
      * @return the serialization filter for the stream; may be null
      * @since 9
      */
-    public final ObjectInputFilter getObjectInputFilter() {
+    public final @Nullable ObjectInputFilter getObjectInputFilter() {
         return serialFilter;
     }
 
@@ -1240,7 +1240,7 @@ public final ObjectInputFilter getObjectInputFilter() {
      *       is not {@code null} and is not the process-wide filter
      * @since 9
      */
-    public final void setObjectInputFilter(ObjectInputFilter filter) {
+    public final void setObjectInputFilter(@Nullable ObjectInputFilter filter) {
         SecurityManager sm = System.getSecurityManager();
         if (sm != null) {
             sm.checkPermission(ObjectStreamConstants.SERIAL_FILTER_PERMISSION);
diff --git a/src/java.base/share/classes/java/io/ObjectOutputStream.java b/src/java.base/share/classes/java/io/ObjectOutputStream.java
index a578e7f942c..c1ad0cbd88e 100644
--- a/src/java.base/share/classes/java/io/ObjectOutputStream.java
+++ b/src/java.base/share/classes/java/io/ObjectOutputStream.java
@@ -373,7 +373,7 @@ public final void writeObject(@Nullable Object obj) throws IOException {
      * @see #writeObject(Object)
      * @since 1.2
      */
-    protected void writeObjectOverride(Object obj) throws IOException {
+    protected void writeObjectOverride(@Nullable Object obj) throws IOException {
     }
 
     /**