PackageElement.java revision 4220:51b4cd2af28e 
1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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.
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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).
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24 */
25
26package javax.lang.model.element;
27
28import java.util.List;
29
30/**
31 * Represents a package program element.  Provides access to information
32 * about the package and its members.
33 *
34 * @author Joseph D. Darcy
35 * @author Scott Seligman
36 * @author Peter von der Ahé
37 * @see javax.lang.model.util.Elements#getPackageOf
38 * @since 1.6
39 */
40public interface PackageElement extends Element, QualifiedNameable {
41
42    /**
43     * Returns the fully qualified name of this package.
44     * This is also known as the package's <i>canonical</i> name.
45     * For an {@linkplain #isUnnamed() unnamed package}, an empty name is returned.
46     *
47     * @apiNote The fully qualified name of a named package that is
48     * not a subpackage of a named package is its simple name. The
49     * fully qualified name of a named package that is a subpackage of
50     * another named package consists of the fully qualified name of
51     * the containing package, followed by "{@code .}", followed by the simple
52     * (member) name of the subpackage.
53     *
54     * @return the fully qualified name of this package, or an
55     * empty name if this is an unnamed package
56     * @jls 6.7 Fully Qualified Names and Canonical Names
57     */
58    Name getQualifiedName();
59
60    /**
61     * Returns the simple name of this package.  For an {@linkplain
62     * #isUnnamed() unnamed package}, an empty name is returned.
63     *
64     * @return the simple name of this package or an empty name if
65     * this is an unnamed package
66     */
67    @Override
68    Name getSimpleName();
69
70    /**
71     * Returns the {@linkplain NestingKind#TOP_LEVEL top-level}
72     * classes and interfaces within this package.  Note that
73     * subpackages are <em>not</em> considered to be enclosed by a
74     * package.
75     *
76     * @return the top-level classes and interfaces within this
77     * package
78     */
79    @Override
80    List<? extends Element> getEnclosedElements();
81
82    /**
83     * Returns {@code true} if this is an unnamed package and {@code
84     * false} otherwise.
85     *
86     * @return {@code true} if this is an unnamed package and {@code
87     * false} otherwise
88     * @jls 7.4.2 Unnamed Packages
89     */
90    boolean isUnnamed();
91
92    /**
93     * Returns the enclosing module if such a module exists; otherwise
94     * returns {@code null}.
95     *
96     * One situation where a module does not exist for a package is if
97     * the environment does not include modules, such as an annotation
98     * processing environment configured for a {@linkplain
99     * javax.annotation.processing.ProcessingEnvironment#getSourceVersion
100     * source version} without modules.
101     *
102     * @return the enclosing module or {@code null} if no such module exists
103     *
104     * @revised 9
105     * @spec JPMS
106     */
107    @Override
108    Element getEnclosingElement();
109}
110