| /* |
| * 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * 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. |
| */ |
| |
| package com.sun.jndi.ldap.spi; |
| |
| import javax.naming.Context; |
| import javax.naming.NamingException; |
| import java.util.Map; |
| |
| /** |
| * Service-provider class for DNS lookups when performing LDAP operations. |
| * |
| * <p> An LDAP DNS provider is a concrete subclass of this class that |
| * has a zero-argument constructor. LDAP DNS providers are located using the |
| * ServiceLoader facility, as specified by |
| * {@linkplain javax.naming.directory.InitialDirContext InitialDirectContext}. |
| * |
| * The |
| * {@link java.util.ServiceLoader ServiceLoader} is used to create and register |
| * implementations of {@code LdapDnsProvider}. |
| * |
| * <p> An LDAP DNS provider can be used in environments where the default |
| * DNS resolution mechanism is not sufficient to accurately pinpoint the |
| * correct LDAP servers needed to perform LDAP operations. For example, in an |
| * environment containing a mix of {@code ldap} and {@code ldaps} servers |
| * you may want the {@linkplain javax.naming.ldap.LdapContext LdapContext} |
| * to query {@code ldaps} servers only. |
| * |
| * @since 12 |
| */ |
| public abstract class LdapDnsProvider { |
| |
| // The {@code RuntimePermission("ldapDnsProvider")} is |
| // necessary to subclass and instantiate the {@code LdapDnsProvider} class. |
| private 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; |
| } |
| |
| /** |
| * Lookup the endpoints and domain name for the given {@link Context} |
| * {@link Context#PROVIDER_URL provider URL} and environment. The resolved |
| * endpoints and domain name are returned as an |
| * {@link LdapDnsProviderResult}. |
| * |
| * <p> An endpoint is a {@code String} representation of an LDAP URL which |
| * points to an LDAP server to be used for LDAP operations. The syntax of |
| * an LDAP URL is defined by <a href="http://www.ietf.org/rfc/rfc2255.txt"> |
| * <i>RFC 2255: The LDAP URL Format</i></a>. |
| * |
| * @param url The {@link Context} {@link Context#PROVIDER_URL provider URL} |
| * @param env The {@link Context} environment. |
| * |
| * @return an {@link LdapDnsProviderResult} or null if the lookup fails. |
| * |
| * @throws NamingException if the {@code url} is not valid or an error |
| * occurred while performing the lookup. |
| * @throws NullPointerException if either {@code url} or {@code env} are |
| * {@code null}. |
| */ |
| public abstract LdapDnsProviderResult lookupEndpoints( |
| String url, Map<?,?> env) throws NamingException; |
| |
| } |