1/**
2 * Copyright 2013 Florian Schmaus
3 *
4 * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16package org.jivesoftware.smack.util.dns;
17
18/**
19 * @see <a href="http://tools.ietf.org/html/rfc2782>RFC 2782: A DNS RR for specifying the location of services (DNS
20 * SRV)<a>
21 * @author Florian Schmaus
22 *
23 */
24public class SRVRecord extends HostAddress implements Comparable<SRVRecord> {
25
26    private int weight;
27    private int priority;
28
29    /**
30     * Create a new SRVRecord
31     *
32     * @param fqdn Fully qualified domain name
33     * @param port The connection port
34     * @param priority Priority of the target host
35     * @param weight Relative weight for records with same priority
36     * @throws IllegalArgumentException fqdn is null or any other field is not in valid range (0-65535).
37     */
38    public SRVRecord(String fqdn, int port, int priority, int weight) {
39        super(fqdn, port);
40        if (weight < 0 || weight > 65535)
41            throw new IllegalArgumentException(
42                    "DNS SRV records weight must be a 16-bit unsiged integer (i.e. between 0-65535. Weight was: "
43                            + weight);
44
45        if (priority < 0 || priority > 65535)
46            throw new IllegalArgumentException(
47                    "DNS SRV records priority must be a 16-bit unsiged integer (i.e. between 0-65535. Priority was: "
48                            + priority);
49
50        this.priority = priority;
51        this.weight = weight;
52
53    }
54
55    public int getPriority() {
56        return priority;
57    }
58
59    public int getWeight() {
60        return weight;
61    }
62
63    @Override
64    public int compareTo(SRVRecord other) {
65        // According to RFC2782,
66        // "[a] client MUST attempt to contact the target host with the lowest-numbered priority it can reach".
67        // This means that a SRV record with a higher priority is 'less' then one with a lower.
68        int res = other.priority - this.priority;
69        if (res == 0) {
70            res = this.weight - other.weight;
71        }
72        return res;
73    }
74
75    @Override
76    public String toString() {
77        return super.toString() + " prio:" + priority + ":w:" + weight;
78    }
79}
80