src/java.base/unix/classes/java/net/PlainDatagramSocketImpl.java

@@ -25,10 +25,11 @@
 package java.net;
 
 import java.io.IOException;
 import java.util.Set;
 import java.util.HashSet;
+import java.util.Iterator;
 import sun.net.ext.ExtendedSocketOptions;
 
 /*
  * On Unix systems we simply delegate to native methods.
  *

@@ -83,14 +84,28 @@
         }
     }
 
     protected Set<SocketOption<?>> supportedOptions() {
         HashSet<SocketOption<?>> options = new HashSet<>(super.supportedOptions());
-        options.addAll(extendedOptions.options());
+        options.addAll(filterSocketOption(extendedOptions.options()));
         return options;
     }
 
+    private Set<SocketOption<?>> filterSocketOption(Set<SocketOption<?>> options) {
+        Set<SocketOption<?>> opt = new HashSet<>(options);
+        final Iterator<SocketOption<?>> iterator = opt.iterator();
+        while (iterator.hasNext()) {
+            SocketOption<?> option = iterator.next();
+            // SO_QUICKACK is applicable for TCP Sockets only.
+            if (option.name().equals("SO_QUICKACK")) {
+                iterator.remove();
+                break;
+            }
+        }
+        return opt;
+    }
+
     protected void socketSetOption(int opt, Object val) throws SocketException {
         if (opt == SocketOptions.SO_REUSEPORT &&
             !supportedOptions().contains(StandardSocketOptions.SO_REUSEPORT)) {
             throw new UnsupportedOperationException("unsupported option");
         }