--- /dev/null	2018-07-30 10:53:35.000000000 +0800
+++ new/test/jdk/com/sun/jndi/dns/EnvTests/ProviderUrlGen.java	2018-07-30 10:53:35.000000000 +0800
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2002, 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.
+ */
+
+/*
+ * @test
+ * @bug 8208279
+ * @summary If DNS name resolution is configured normally for SWAN on the local
+ *          machine, construct a context using the configured servers and verify
+ *          that a PROVIDER_URL property is generated for the context.
+ *          If DNS is not configured, or if JDK version is earlier than 1.4.1,
+ *          then this test is a no-op (it passes without doing anything).
+ * @library ../lib/
+ * @modules jdk.naming.dns/com.sun.jndi.dns
+ *          java.base/sun.security.util
+ * @run main ProviderUrlGen
+ */
+
+import javax.naming.Context;
+import javax.naming.directory.InitialDirContext;
+
+public class ProviderUrlGen extends DNSTestBase {
+
+    public ProviderUrlGen() {
+        setLocalServer(false);
+    }
+
+    public static void main(String[] args) throws Exception {
+        if (!isPlatformServersAvailable()) {
+            DNSTestUtils.debug("DNS not configured. There's nothing to test.");
+            return;
+        }
+
+        new ProviderUrlGen().run(args);
+    }
+
+    @Override public void runTest() throws Exception {
+        initContext();
+
+        String providerUrl = (String) context().getEnvironment()
+                .get(Context.PROVIDER_URL);
+
+        if (providerUrl == null) {
+            throw new RuntimeException("Failed: PROVIDER_URL not set");
+        }
+
+        DNSTestUtils.debug("PROVIDER_URL = \"" + providerUrl + "\"");
+
+        // We don't know exactly what providerUrl's value should be.
+        // Check that it is a space-separated list of one or more URLs
+        // of the form "dns://xxxxxx".
+
+        String[] urls = providerUrl.split(" ");
+        if (urls.length < 1) {
+            throw new RuntimeException("Failed:  PROVIDER_URL is empty");
+        }
+
+        for (String url : urls) {
+            DNSTestUtils.debug(url);
+            if (!checkUrl(url)) {
+                throw new RuntimeException(
+                        "Failed:  Unexpected DNS URL: " + url);
+            }
+        }
+    }
+
+    private void initContext() throws Exception {
+        env().remove(Context.PROVIDER_URL);
+        setContext(new InitialDirContext(env()));
+    }
+
+    private static boolean checkUrl(String url) {
+        return url.startsWith("dns://") && url.length() >= 7;
+    }
+
+    private static boolean isPlatformServersAvailable() {
+        try {
+            java.lang.reflect.Method psa = com.sun.jndi.dns.DnsContextFactory.class
+                    .getMethod("platformServersAvailable", null);
+            return (Boolean) psa.invoke(null, null);
+        } catch (Exception e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+}