1 /*
2 * Portions of this software was developed by employees of the National Institute
3 * of Standards and Technology (NIST), an agency of the Federal Government and is
4 * being made available as a public service. Pursuant to title 17 United States
5 * Code Section 105, works of NIST employees are not subject to copyright
6 * protection in the United States. This software may be subject to foreign
7 * copyright. Permission in the United States and in foreign countries, to the
8 * extent that NIST may hold copyright, to use, copy, modify, create derivative
9 * works, and distribute this software and its documentation without fee is hereby
10 * granted on a non-exclusive basis, provided that this notice and disclaimer
11 * of warranty appears in all copies.
12 *
13 * THE SOFTWARE IS PROVIDED 'AS IS' WITHOUT ANY WARRANTY OF ANY KIND, EITHER
14 * EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY
15 * THAT THE SOFTWARE WILL CONFORM TO SPECIFICATIONS, ANY IMPLIED WARRANTIES OF
16 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND FREEDOM FROM
17 * INFRINGEMENT, AND ANY WARRANTY THAT THE DOCUMENTATION WILL CONFORM TO THE
18 * SOFTWARE, OR ANY WARRANTY THAT THE SOFTWARE WILL BE ERROR FREE. IN NO EVENT
19 * SHALL NIST BE LIABLE FOR ANY DAMAGES, INCLUDING, BUT NOT LIMITED TO, DIRECT,
20 * INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES, ARISING OUT OF, RESULTING FROM,
21 * OR IN ANY WAY CONNECTED WITH THIS SOFTWARE, WHETHER OR NOT BASED UPON WARRANTY,
22 * CONTRACT, TORT, OR OTHERWISE, WHETHER OR NOT INJURY WAS SUSTAINED BY PERSONS OR
23 * PROPERTY OR OTHERWISE, AND WHETHER OR NOT LOSS WAS SUSTAINED FROM, OR AROSE OUT
24 * OF THE RESULTS OF, OR USE OF, THE SOFTWARE OR SERVICES PROVIDED HEREUNDER.
25 */
26
27 package gov.nist.secauto.metaschema.core.metapath.function;
28
29 import gov.nist.secauto.metaschema.core.metapath.item.IItem;
30
31 import edu.umd.cs.findbugs.annotations.NonNull;
32
33 public interface ISequenceType {
34 @NonNull
35 ISequenceType EMPTY = new ISequenceType() {
36 @Override
37 public boolean isEmpty() {
38 return true;
39 }
40
41 @Override
42 public Class<? extends IItem> getType() {
43 return null;
44 }
45
46 @Override
47 public Occurrence getOccurrence() {
48 return null;
49 }
50
51 @Override
52 public String toSignature() {
53 return "()";
54 }
55 };
56
57 /**
58 * Determine if the sequence is empty (if it holds any data) or not.
59 *
60 * @return {@code true} if the sequence is empty or {@code false} otherwise
61 */
62 boolean isEmpty();
63
64 /**
65 * Get the type of the sequence.
66 *
67 * @return the type of the sequence or {@code null} if the sequence is empty
68 */
69 Class<? extends IItem> getType();
70
71 /**
72 * Get the occurrence of the sequence.
73 *
74 * @return the occurrence of the sequence or {@code null} if the sequence is
75 * empty
76 */
77 Occurrence getOccurrence();
78
79 /**
80 * Get the signature of the function as a string.
81 *
82 * @return the signature
83 */
84 String toSignature();
85 }