1/*
2 * Copyright (c) 2003, 2004, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package javax.naming.ldap;
27
28/**
29 * A sort key and its associated sort parameters.
30 * This class implements a sort key which is used by the LDAPv3
31 * Control for server-side sorting of search results as defined in
32 * <a href="http://www.ietf.org/rfc/rfc2891.txt">RFC 2891</a>.
33 *
34 * @since 1.5
35 * @see SortControl
36 * @author Vincent Ryan
37 */
38public class SortKey {
39
40    /*
41     * The ID of the attribute to sort by.
42     */
43    private String attrID;
44
45    /*
46     * The sort order. Ascending order, by default.
47     */
48    private boolean reverseOrder = false;
49
50    /*
51     * The ID of the matching rule to use for ordering attribute values.
52     */
53    private String matchingRuleID = null;
54
55    /**
56     * Creates the default sort key for an attribute. Entries will be sorted
57     * according to the specified attribute in ascending order using the
58     * ordering matching rule defined for use with that attribute.
59     *
60     * @param   attrID  The non-null ID of the attribute to be used as a sort
61     *          key.
62     */
63    public SortKey(String attrID) {
64        this.attrID = attrID;
65    }
66
67    /**
68     * Creates a sort key for an attribute. Entries will be sorted according to
69     * the specified attribute in the specified sort order and using the
70     * specified matching rule, if supplied.
71     *
72     * @param   attrID          The non-null ID of the attribute to be used as
73     *                          a sort key.
74     * @param   ascendingOrder  If true then entries are arranged in ascending
75     *                          order. Otherwise there are arranged in
76     *                          descending order.
77     * @param   matchingRuleID  The possibly null ID of the matching rule to
78     *                          use to order the attribute values. If not
79     *                          specified then the ordering matching rule
80     *                          defined for the sort key attribute is used.
81     */
82    public SortKey(String attrID, boolean ascendingOrder,
83                    String matchingRuleID) {
84
85        this.attrID = attrID;
86        reverseOrder = (! ascendingOrder);
87        this.matchingRuleID = matchingRuleID;
88    }
89
90    /**
91     * Retrieves the attribute ID of the sort key.
92     *
93     * @return    The non-null Attribute ID of the sort key.
94     */
95    public String getAttributeID() {
96        return attrID;
97    }
98
99    /**
100     * Determines the sort order.
101     *
102     * @return    true if the sort order is ascending, false if descending.
103     */
104    public boolean isAscending() {
105        return (! reverseOrder);
106    }
107
108    /**
109     * Retrieves the matching rule ID used to order the attribute values.
110     *
111     * @return    The possibly null matching rule ID. If null then the
112     *            ordering matching rule defined for the sort key attribute
113     *            is used.
114     */
115    public String getMatchingRuleID() {
116        return matchingRuleID;
117    }
118}
119