1 /*
2 * Copyright 2020-2022 Foreseeti AB <https://foreseeti.com>
3 *
4 * 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 */
16
17 package org.mal_lang.langspec;
18
19 import static java.util.Objects.requireNonNull;
20
21 import jakarta.json.Json;
22 import jakarta.json.JsonObject;
23
24 /**
25 * Enum representing the multiplicity of a field of an asset in a MAL language.
26 *
27 * @since 1.0.0
28 */
29 public enum Multiplicity {
30 /**
31 * Enum constant representing the multiplicity {@code 0..1}.
32 *
33 * @since 1.0.0
34 */
35 ZERO_OR_ONE(0, 1),
36
37 /**
38 * Enum constant representing the multiplicity {@code 0..*} / {@code *}.
39 *
40 * @since 1.0.0
41 */
42 ZERO_OR_MORE(0, Integer.MAX_VALUE),
43
44 /**
45 * Enum constant representing the multiplicity {@code 1..1} / {@code 1}.
46 *
47 * @since 1.0.0
48 */
49 ONE(1, 1),
50
51 /**
52 * Enum constant representing the multiplicity {@code 1..*}.
53 *
54 * @since 1.0.0
55 */
56 ONE_OR_MORE(1, Integer.MAX_VALUE);
57
58 private final int min;
59 private final int max;
60
61 Multiplicity(int min, int max) {
62 this.min = min;
63 this.max = max;
64 }
65
66 /**
67 * Returns the minimum of this {@code Multiplicity} object.
68 *
69 * @return the minimum of this {@code Multiplicity} object
70 * @since 1.0.0
71 */
72 public int getMin() {
73 return this.min;
74 }
75
76 /**
77 * Returns the maximum of this {@code Multiplicity} object.
78 *
79 * @return the maximum of this {@code Multiplicity} object
80 * @since 1.0.0
81 */
82 public int getMax() {
83 return this.max;
84 }
85
86 JsonObject toJson() {
87 var jsonMultiplicity = Json.createObjectBuilder().add("min", this.min);
88 if (this.max == Integer.MAX_VALUE) {
89 jsonMultiplicity.addNull("max");
90 } else {
91 jsonMultiplicity.add("max", this.max);
92 }
93 return jsonMultiplicity.build();
94 }
95
96 /**
97 * Creates a new {@code Multiplicity} from a {@link jakarta.json.JsonObject}.
98 *
99 * @param jsonMultiplicity the {@link jakarta.json.JsonObject}
100 * @return a new {@code Multiplicity}
101 * @throws java.lang.NullPointerException if {@code jsonMultiplicity} is {@code null}
102 * @since 1.0.0
103 */
104 public static Multiplicity fromJson(JsonObject jsonMultiplicity) {
105 requireNonNull(jsonMultiplicity);
106 int min = jsonMultiplicity.getInt("min");
107 int max = jsonMultiplicity.isNull("max") ? Integer.MAX_VALUE : jsonMultiplicity.getInt("max");
108 if (min == 0 && max == 1) {
109 return ZERO_OR_ONE;
110 }
111 if (min == 0 && max == Integer.MAX_VALUE) {
112 return ZERO_OR_MORE;
113 }
114 if (min == 1 && max == 1) {
115 return ONE;
116 }
117 if (min == 1 && max == Integer.MAX_VALUE) {
118 return ONE_OR_MORE;
119 }
120 throw new RuntimeException(
121 String.format("Invalid multiplicity {min = %d, max = %d}", min, max));
122 }
123 }