--- /dev/null	2017-12-06 15:25:09.752000052 +0000
+++ new/src/java.naming/share/classes/javax/naming/spi/ldap/LdapDnsProvider.java	2017-12-06 17:43:08.087424920 +0000
@@ -0,0 +1,61 @@
+package javax.naming.spi.ldap;
+
+import java.util.Hashtable;
+
+/**
+ * DNS provider abstract class whose concrete implementations are used by
+ * {@code com.sun.jndi.ldap.LdapCtxFactory.getUsingURL()} to resolve ldap
+ * server urls.
+ *
+ * The ServiceLoader is used to create and register implementations of
+ * {@code LdapDnsProvider}.
+ *
+ * A DNS provider must subclass the {@link LdapDnsProvider} class.
+ * In addition, the provider class must be public and must have a
+ * public constructor that accepts no parameters.
+ */
+public abstract class LdapDnsProvider {
+
+    /**
+     * The {@code RuntimePermission("ldapDnsProvider")} is
+     * necessary to subclass and instantiate the {@code LdapDnsProvider} class.
+     */
+    public static final RuntimePermission DNSPROVIDER_PERMISSION =
+            new RuntimePermission("ldapDnsProvider");
+
+    /**
+     * Creates a new instance of {@code LdapDnsProvider}.
+     *
+     * @throws SecurityException if a security manager is present and its
+     *         {@code checkPermission} method doesn't allow the
+     *         {@code RuntimePermission("ldapDnsProvider")}.
+     */
+    protected LdapDnsProvider() {
+        this(checkPermission());
+    }
+
+    private LdapDnsProvider(Void unused) {
+        // nothing to do.
+    }
+
+    private static Void checkPermission() {
+        final SecurityManager sm = System.getSecurityManager();
+        if (sm != null) {
+            sm.checkPermission(DNSPROVIDER_PERMISSION);
+        }
+        return null;
+    }
+
+    /**
+     * The {@code lookupEndpoints(String url, Hashtable<?,?> env)} method
+     * takes two parameters:
+     *
+     * @param url   The {@code Context.PROVIDER_URL}
+     * @param env   The LdapCtx environment properties.
+     *
+     * @return  an {@link LdapDnsProviderResult}.
+     */
+    public abstract LdapDnsProviderResult lookupEndpoints(
+            String url, Hashtable<?,?> env);
+
+}