--- old/test/jdk/com/sun/jndi/dns/lib/DNSTestUtils.java	2018-03-22 09:58:53.000000000 +0800
+++ new/test/jdk/com/sun/jndi/dns/lib/DNSTestUtils.java	2018-03-22 09:58:52.000000000 +0800
@@ -24,6 +24,7 @@
 import javax.naming.Context;
 import javax.naming.NamingException;
 import javax.naming.directory.Attributes;
+import java.io.Closeable;
 import java.io.PrintStream;
 import java.net.DatagramSocket;
 import java.nio.file.Files;
@@ -149,6 +150,19 @@
         }
     }
 
+    /*
+     * Clean up given closable resource
+     */
+    public static void cleanupClosableRes(Closeable res) {
+        if (res != null) {
+            try {
+                res.close();
+            } catch (Exception e) {
+                // ignore
+            }
+        }
+    }
+
     private static void extractProperty(String propString,
             Hashtable<Object, Object> env) {
         int index;
@@ -243,4 +257,21 @@
             throw new RuntimeException("Check schema failed.");
         }
     }
+
+    public static String getRootUrl(Hashtable<Object, Object> env) {
+        return (String) env.get(TEST_DNS_ROOT_URL);
+    }
+
+    /*
+     * Assemble a fully-qualified domain name from the base component and the
+     * domain name.
+     */
+    public static String buildFqdn(String base, Hashtable<Object, Object> env,
+            boolean primary) {
+        String domain = (String) (primary ?
+                env.get("DNS_DOMAIN") :
+                env.get("FOREIGN_DOMAIN"));
+
+        return base + "." + domain;
+    }
 }