diff --git a/src/java.smartcardio/share/classes/javax/smartcardio/ATR.java b/src/java.smartcardio/share/classes/javax/smartcardio/ATR.java
index 49537c394e5..85cfa53a0db 100644
--- a/src/java.smartcardio/share/classes/javax/smartcardio/ATR.java
+++ b/src/java.smartcardio/share/classes/javax/smartcardio/ATR.java
@@ -25,6 +25,8 @@
 
 package javax.smartcardio;
 
+import java.io.IOException;
+import java.io.Serial;
 import java.util.*;
 
 /**
@@ -44,8 +46,10 @@ import java.util.*;
  */
 public final class ATR implements java.io.Serializable {
 
+    @Serial
     private static final long serialVersionUID = 6695383790847736493L;
 
+    /** ATR byte array. */
     private byte[] atr;
 
     private transient int startHistorical, nHistorical;
@@ -156,6 +160,13 @@ public final class ATR implements java.io.Serializable {
         return Arrays.hashCode(atr);
     }
 
+    /**
+     * Reconstitute this object from a stream.
+     *
+     * @param  in the {@code ObjectInputStream} from which data is read
+     * @throws IOException if an I/O error occurs
+     * @throws ClassNotFoundException if a serialized class cannot be loaded
+     */
     private void readObject(java.io.ObjectInputStream in)
             throws java.io.IOException, ClassNotFoundException {
         atr = (byte[])in.readUnshared();
diff --git a/src/java.smartcardio/share/classes/javax/smartcardio/CardPermission.java b/src/java.smartcardio/share/classes/javax/smartcardio/CardPermission.java
index b70de530cf1..02b0d6107fc 100644
--- a/src/java.smartcardio/share/classes/javax/smartcardio/CardPermission.java
+++ b/src/java.smartcardio/share/classes/javax/smartcardio/CardPermission.java
@@ -280,11 +280,24 @@ public class CardPermission extends Permission {
         return getName().hashCode() + 31 * mask;
     }
 
+    /**
+     * Saves this object to a stream.
+     *
+     * @param  s the {@code ObjectOutputStream} to which data is written
+     * @throws IOException if an I/O error occurs
+     */
     private void writeObject(ObjectOutputStream s) throws IOException {
         // Write out the actions. The superclass takes care of the name.
         s.defaultWriteObject();
     }
 
+    /**
+     * Reconstitute this object from a stream.
+     *
+     * @param  s the {@code ObjectInputStream} from which data is read
+     * @throws IOException if an I/O error occurs
+     * @throws ClassNotFoundException if a serialized class cannot be loaded
+     */
     private void readObject(ObjectInputStream s)
             throws IOException, ClassNotFoundException {
         // Read in the actions, then restore the mask.
diff --git a/src/java.smartcardio/share/classes/javax/smartcardio/CommandAPDU.java b/src/java.smartcardio/share/classes/javax/smartcardio/CommandAPDU.java
index 9f538913215..deaff4074d4 100644
--- a/src/java.smartcardio/share/classes/javax/smartcardio/CommandAPDU.java
+++ b/src/java.smartcardio/share/classes/javax/smartcardio/CommandAPDU.java
@@ -25,6 +25,7 @@
 
 package javax.smartcardio;
 
+import java.io.IOException;
 import java.util.Arrays;
 
 import java.nio.ByteBuffer;
@@ -596,6 +597,13 @@ public final class CommandAPDU implements java.io.Serializable {
         return Arrays.hashCode(apdu);
     }
 
+    /**
+     * Reconstitute this object from a stream.
+     *
+     * @param  in the {@code ObjectInputStream} from which data is read
+     * @throws IOException if an I/O error occurs
+     * @throws ClassNotFoundException if a serialized class cannot be loaded
+     */
     private void readObject(java.io.ObjectInputStream in)
             throws java.io.IOException, ClassNotFoundException {
         apdu = (byte[])in.readUnshared();
diff --git a/src/java.smartcardio/share/classes/javax/smartcardio/ResponseAPDU.java b/src/java.smartcardio/share/classes/javax/smartcardio/ResponseAPDU.java
index e9850da1fc3..3ed565ecb6b 100644
--- a/src/java.smartcardio/share/classes/javax/smartcardio/ResponseAPDU.java
+++ b/src/java.smartcardio/share/classes/javax/smartcardio/ResponseAPDU.java
@@ -25,6 +25,7 @@
 
 package javax.smartcardio;
 
+import java.io.IOException;
 import java.util.Arrays;
 
 /**
@@ -176,6 +177,13 @@ public final class ResponseAPDU implements java.io.Serializable {
         return Arrays.hashCode(apdu);
     }
 
+    /**
+     * Reconstitute this object from a stream.
+     *
+     * @param  in the {@code ObjectInputStream} from which data is read
+     * @throws IOException if an I/O error occurs
+     * @throws ClassNotFoundException if a serialized class cannot be loaded
+     */
     private void readObject(java.io.ObjectInputStream in)
             throws java.io.IOException, ClassNotFoundException {
         apdu = (byte[])in.readUnshared();
diff --git a/src/java.smartcardio/share/classes/javax/smartcardio/TerminalFactory.java b/src/java.smartcardio/share/classes/javax/smartcardio/TerminalFactory.java
index 21b8459c947..efd85d096a6 100644
--- a/src/java.smartcardio/share/classes/javax/smartcardio/TerminalFactory.java
+++ b/src/java.smartcardio/share/classes/javax/smartcardio/TerminalFactory.java
@@ -129,6 +129,9 @@ public final class TerminalFactory {
         defaultFactory = factory;
     }
 
+    /**
+     * A simple None Provider.
+     */
     private static final class NoneProvider extends Provider {
 
         private static final long serialVersionUID = 2745808869881593918L;