1 /*
2 * Copyright (c) 2005, 2018, 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
26 package javax.annotation.processing;
27
28 import javax.lang.model.element.Element;
29 import javax.lang.model.element.TypeElement;
30 import java.util.LinkedHashSet;
31 import java.util.Collections;
32 import java.util.Set;
33 import java.lang.annotation.Annotation;
34
35 /**
36 * An annotation processing tool framework will {@linkplain
37 * Processor#process provide an annotation processor with an object
38 * implementing this interface} so that the processor can query for
39 * information about a round of annotation processing.
40 *
41 * @author Joseph D. Darcy
42 * @author Scott Seligman
43 * @author Peter von der Ahé
44 * @since 1.6
45 */
46 public interface RoundEnvironment {
47 /**
48 * Returns {@code true} if types generated by this round will not
49 * be subject to a subsequent round of annotation processing;
50 * returns {@code false} otherwise.
51 *
52 * @return {@code true} if types generated by this round will not
53 * be subject to a subsequent round of annotation processing;
54 * returns {@code false} otherwise
55 */
56 boolean processingOver();
57
58 /**
59 * Returns {@code true} if an error was raised in the prior round
60 * of processing; returns {@code false} otherwise.
61 *
62 * @return {@code true} if an error was raised in the prior round
63 * of processing; returns {@code false} otherwise
64 */
65 boolean errorRaised();
66
67 /**
68 * Returns the {@linkplain Processor root elements} for annotation processing generated
69 * by the prior round.
70 *
71 * @return the root elements for annotation processing generated
72 * by the prior round, or an empty set if there were none
73 */
74 Set<? extends Element> getRootElements();
75
76 /**
77 * Returns the elements annotated with the given annotation type.
78 * The annotation may appear directly or be inherited. Only
79 * package elements, module elements, and type elements <i>included</i> in this
80 * round of annotation processing, or declarations of members,
81 * constructors, parameters, or type parameters declared within
82 * those, are returned. Included type elements are {@linkplain
83 * #getRootElements root types} and any member types nested within
84 * them. Elements of a package are not considered included simply
85 * because a {@code package-info} file for that package was
86 * created.
87 * Likewise, elements of a module are not considered included
88 * simply because a {@code module-info} file for that module was
89 * created.
90 *
91 * @param a annotation type being requested
92 * @return the elements annotated with the given annotation type,
93 * or an empty set if there are none
94 * @throws IllegalArgumentException if the argument does not
95 * represent an annotation type
96 */
97 Set<? extends Element> getElementsAnnotatedWith(TypeElement a);
98
99 /**
100 * Returns the elements annotated with one or more of the given
101 * annotation types.
102 *
103 * @apiNote This method may be useful when processing repeating
104 * annotations by looking for an annotation type and its
105 * containing annotation type at the same time.
106 *
107 * @implSpec The default implementation of this method creates an
108 * empty result set, iterates over the annotations in the argument
109 * array calling {@link #getElementsAnnotatedWith(TypeElement)} on
110 * each annotation and adding those results to the result
111 * set. Finally, the contents of the result set are returned as an
112 * unmodifiable set.
113 *
114 * @param annotations annotation types being requested
115 * @return the elements annotated with one or more of the given
116 * annotation types, or an empty set if there are none
117 * @throws IllegalArgumentException if the any elements of the
118 * argument set do not represent an annotation type
119 * @jls 9.6.3 Repeatable Annotation Types
120 * @since 9
121 */
122 default Set<? extends Element> getElementsAnnotatedWithAny(TypeElement... annotations){
123 // Use LinkedHashSet rather than HashSet for predictability
124 Set<Element> result = new LinkedHashSet<>();
125 for (TypeElement annotation : annotations) {
126 result.addAll(getElementsAnnotatedWith(annotation));
127 }
128 return Collections.unmodifiableSet(result);
129 }
130
131 /**
132 * Returns the elements annotated with the given annotation type.
133 * The annotation may appear directly or be inherited. Only
134 * package elements, module elements, and type elements <i>included</i> in this
135 * round of annotation processing, or declarations of members,
136 * constructors, parameters, or type parameters declared within
137 * those, are returned. Included type elements are {@linkplain
138 * #getRootElements root types} and any member types nested within
139 * them. Elements in a package are not considered included simply
140 * because a {@code package-info} file for that package was
141 * created.
142 * Likewise, elements of a module are not considered included
143 * simply because a {@code module-info} file for that module was
144 * created.
145 *
146 * <p> Note: An implementation of this method typically performs
147 * an internal conversion from the runtime reflective
148 * representation of an annotation type as a {@code Class} object
149 * to a different representation used for annotation
150 * processing. The set of annotation types present in the runtime
151 * context may differ from the set of annotation types present in
152 * the context of annotation processing in a particular
153 * environmental configuration. If an runtime annotation type is
154 * not present in the annotation processing context, the situation
155 * is not treated as an error and no elements are found for that
156 * annotation type.
157 *
158 * @param a annotation type being requested
159 * @return the elements annotated with the given annotation type,
160 * or an empty set if there are none
161 * @throws IllegalArgumentException if the argument does not
162 * represent an annotation type
163 *
164 * @see AnnotatedConstruct.getAnnotation(Class)
165 * @see AnnotatedConstruct.getAnnotationsByType(Class)
166 */
167 Set<? extends Element> getElementsAnnotatedWith(Class<? extends Annotation> a);
168
169 /**
170 * Returns the elements annotated with one or more of the given
171 * annotation types.
172 *
173 * <p> Note: An implementation of this method typically performs
174 * an internal conversion from the runtime reflective
175 * representation of an annotation type as a {@code Class} object
176 * to a different representation used for annotation
177 * processing. The set of annotation types present in the runtime
178 * context may differ from the set of annotation types present in
179 * the context of annotation processing in a particular
180 * environmental configuration. If an runtime annotation type is
181 * not present in the annotation processing context, the situation
182 * is not treated as an error and no elements are found for that
183 * annotation type.
184 *
185 * @apiNote This method may be useful when processing repeating
186 * annotations by looking for an annotation type and its
187 * containing annotation type at the same time.
188 *
189 * @implSpec The default implementation of this method creates an
190 * empty result set, iterates over the annotations in the argument
191 * set calling {@link #getElementsAnnotatedWith(Class)} on
192 * each annotation and adding those results to the result
193 * set. Finally, the contents of the result set are returned as an
194 * unmodifiable set.
195 *
196 * @param annotations annotation types being requested
197 * @return the elements annotated with one or more of the given
198 * annotation types, or an empty set if there are none
199 * @throws IllegalArgumentException if the any elements of the
200 * argument set do not represent an annotation type
201 * @jls 9.6.3 Repeatable Annotation Types
202 *
203 * @see AnnotatedConstruct.getAnnotation(Class)
204 * @see AnnotatedConstruct.getAnnotationsByType(Class)
205 *
206 * @since 9
207 */
208 default Set<? extends Element> getElementsAnnotatedWithAny(Set<Class<? extends Annotation>> annotations){
209 // Use LinkedHashSet rather than HashSet for predictability
210 Set<Element> result = new LinkedHashSet<>();
211 for (Class<? extends Annotation> annotation : annotations) {
212 result.addAll(getElementsAnnotatedWith(annotation));
213 }
214 return Collections.unmodifiableSet(result);
215 }
216 }