8276447: Deprecate finalization-related methods for removal

Reviewed-by: rriggs, alanb, lancea, darcy, mchung, serb, smarks, prr

src/java.base/share/classes/java/lang/Runtime.java

@@ -707,8 +707,17 @@ public class Runtime {
      * The method {@link System#runFinalization()} is the conventional
      * and convenient means of invoking this method.
      *
+     * @deprecated Finalization has been deprecated for removal.  See
+     * {@link java.lang.Object#finalize} for background information and details
+     * about migration options.
+     * <p>
+     * When running in a JVM in which finalization has been disabled or removed,
+     * no objects will be pending finalization, so this method does nothing.
+     *
      * @see     java.lang.Object#finalize()
+     * @jls 12.6 Finalization of Class Instances
      */
+    @Deprecated(since="18", forRemoval=true)
     public void runFinalization() {
         SharedSecrets.getJavaLangRefAccess().runFinalization();
     }