--- /dev/null	2018-03-22 09:59:29.000000000 +0800
+++ new/test/jdk/com/sun/jndi/dns/lib/DNSTestBase.java	2018-03-22 09:59:29.000000000 +0800
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import javax.naming.directory.DirContext;
+import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.util.Hashtable;
+
+public abstract class DNSTestBase extends TestBase {
+    private DatagramSocket socket;
+    private Hashtable<Object, Object> env;
+    private DirContext ctx;
+
+    @Override public void initRes() throws Exception {
+        // Create socket on localhost only to avoid possible noise packet
+        socket = new DatagramSocket(0, InetAddress.getLoopbackAddress());
+    }
+
+    @Override public void initTest(String[] args) {
+        env = DNSTestUtils.initEnv(socket, this.getClass().getName(), args);
+    }
+
+    @Override public void cleanupTest() {
+        DNSTestUtils.cleanup(ctx);
+        DNSTestUtils.cleanupClosableRes(socket);
+    }
+
+    public Hashtable<Object, Object> env() {
+        if (env == null) {
+            throw new RuntimeException("Test had not been initialized");
+        }
+
+        return env;
+    }
+
+    public DirContext context() {
+        if (ctx == null) {
+            throw new RuntimeException("Context had not been initialized");
+        }
+
+        return ctx;
+    }
+
+    public void setContext(DirContext context) {
+        ctx = context;
+    }
+}