| /* |
| * Copyright (c) 2002, 2010, 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 sun.net.dns; |
| |
| import java.util.List; |
| |
| /** |
| * The configuration of the client resolver. |
| * |
| * <p>A ResolverConfiguration is a singleton that represents the |
| * configuration of the client resolver. The ResolverConfiguration |
| * is opened by invoking the {@link #open() open} method. |
| * |
| * @since 1.4 |
| */ |
| |
| public abstract class ResolverConfiguration { |
| |
| private static final Object lock = new Object(); |
| |
| private static ResolverConfiguration provider; |
| |
| protected ResolverConfiguration() { } |
| |
| /** |
| * Opens the resolver configuration. |
| * |
| * @return the resolver configuration |
| */ |
| public static ResolverConfiguration open() { |
| synchronized (lock) { |
| if (provider == null) { |
| provider = new sun.net.dns.ResolverConfigurationImpl(); |
| } |
| return provider; |
| } |
| } |
| |
| /** |
| * Returns a list corresponding to the domain search path. The |
| * list is ordered by the search order used for host name lookup. |
| * Each element in the list returns a {@link java.lang.String} |
| * containing a domain name or suffix. |
| * |
| * @return list of domain names |
| */ |
| public abstract List<String> searchlist(); |
| |
| /** |
| * Returns a list of name servers used for host name lookup. |
| * Each element in the list returns a {@link java.lang.String} |
| * containing the textual representation of the IP address of |
| * the name server. |
| * |
| * @return list of the name servers |
| */ |
| public abstract List<String> nameservers(); |
| |
| |
| /** |
| * Options representing certain resolver variables of |
| * a {@link ResolverConfiguration}. |
| */ |
| public abstract static class Options { |
| |
| /** |
| * Returns the maximum number of attempts the resolver |
| * will connect to each name server before giving up |
| * and returning an error. |
| * |
| * @return the resolver attempts value or -1 is unknown |
| */ |
| public int attempts() { |
| return -1; |
| } |
| |
| /** |
| * Returns the basic retransmit timeout, in milliseconds, |
| * used by the resolver. The resolver will typically use |
| * an exponential backoff algorithm where the timeout is |
| * doubled for every retransmit attempt. The basic |
| * retransmit timeout, returned here, is the initial |
| * timeout for the exponential backoff algorithm. |
| * |
| * @return the basic retransmit timeout value or -1 |
| * if unknown |
| */ |
| public int retrans() { |
| return -1; |
| } |
| } |
| |
| /** |
| * Returns the {@link #Options} for the resolver. |
| * |
| * @return options for the resolver |
| */ |
| public abstract Options options(); |
| } |