src/java.base/share/classes/java/util/PriorityQueue.java

*** 85,94 ****
--- 85,95 ----
   */
  @SuppressWarnings("unchecked")
  public class PriorityQueue<E> extends AbstractQueue<E>
      implements java.io.Serializable {
  
+     @java.io.Serial
      private static final long serialVersionUID = -7720805057305804111L;
  
      private static final int DEFAULT_INITIAL_CAPACITY = 11;
  
      /**
*** 753,762 ****
--- 754,764 ----
       * @throws java.io.IOException if an I/O error occurs
       * @serialData The length of the array backing the instance is
       *             emitted (int), followed by all of its elements
       *             (each an {@code Object}) in the proper order.
       */
+     @java.io.Serial
      private void writeObject(java.io.ObjectOutputStream s)
          throws java.io.IOException {
          // Write out element count, and any hidden stuff
          s.defaultWriteObject();
  
*** 776,785 ****
--- 778,788 ----
       * @param s the stream
       * @throws ClassNotFoundException if the class of a serialized object
       *         could not be found
       * @throws java.io.IOException if an I/O error occurs
       */
+     @java.io.Serial
      private void readObject(java.io.ObjectInputStream s)
          throws java.io.IOException, ClassNotFoundException {
          // Read in size, and any hidden stuff
          s.defaultReadObject();