View Javadoc
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.builders.step;
18  
19  import static java.util.Objects.requireNonNull;
20  
21  import jakarta.json.JsonObject;
22  import java.util.List;
23  import java.util.Map;
24  import org.mal_lang.langspec.Asset;
25  import org.mal_lang.langspec.builders.AssetBuilder;
26  
27  /**
28   * A builder for creating {@link org.mal_lang.langspec.step.StepExpression} objects.
29   *
30   * @since 1.0.0
31   */
32  public abstract class StepExpressionBuilder {
33    /**
34     * Constructs a new {@code StepExpressionBuilder} object.
35     *
36     * @since 1.0.0
37     */
38    protected StepExpressionBuilder() {}
39  
40    /**
41     * Returns the target asset of this {@code StepExpressionBuilder}.
42     *
43     * @param sourceAsset the source asset
44     * @param assets all assets of the language
45     * @param assetBuilders all asset builders of the language
46     * @return the target asset of this {@code StepExpressionBuilder}
47     * @since 1.0.0
48     */
49    public abstract Asset getTarget(
50        Asset sourceAsset, Map<String, Asset> assets, List<AssetBuilder> assetBuilders);
51  
52    /**
53     * Creates a new {@code StepExpressionBuilder} from a {@link jakarta.json.JsonObject}.
54     *
55     * @param jsonStepExpression the {@link jakarta.json.JsonObject}
56     * @return a new {@code StepExpressionBuilder}
57     * @throws java.lang.NullPointerException if {@code jsonStepExpression} is {@code null}
58     * @since 1.0.0
59     */
60    public static StepExpressionBuilder fromJson(JsonObject jsonStepExpression) {
61      requireNonNull(jsonStepExpression);
62      switch (jsonStepExpression.getString("type")) {
63        case "union":
64        case "intersection":
65        case "difference":
66        case "collect":
67          return StepBinaryOperationBuilder.fromJson(jsonStepExpression);
68        case "transitive":
69          return StepTransitiveBuilder.fromJson(jsonStepExpression);
70        case "subType":
71          return StepSubTypeBuilder.fromJson(jsonStepExpression);
72        case "field":
73        case "attackStep":
74        case "variable":
75          return StepReferenceBuilder.fromJson(jsonStepExpression);
76        default:
77          throw new RuntimeException(
78              String.format(
79                  "Invalid step expression type \"%s\"", jsonStepExpression.getString("type")));
80      }
81    }
82  }