001 /*
002 * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation. Sun designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Sun in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
018 * 2 along with this work; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022 * CA 95054 USA or visit www.sun.com if you need additional information or
023 * have any questions.
024 */
025
026 package javax.lang.model.util;
027
028
029 import java.util.List;
030 import java.util.Map;
031
032 import javax.lang.model.element.*;
033 import javax.lang.model.type.*;
034
035
036 /**
037 * Utility methods for operating on program elements.
038 *
039 * <p><b>Compatibility Note:</b> Methods may be added to this interface
040 * in future releases of the platform.
041 *
042 * @author Joseph D. Darcy
043 * @author Scott Seligman
044 * @author Peter von der Ahé
045 * @see javax.annotation.processing.ProcessingEnvironment#getElementUtils
046 * @since 1.6
047 */
048 public interface Elements {
049
050 /**
051 * Returns a package given its fully qualified name.
052 *
053 * @param name fully qualified package name, or "" for an unnamed package
054 * @return the named package, or {@code null} if it cannot be found
055 */
056 PackageElement getPackageElement(CharSequence name);
057
058 /**
059 * Returns a type element given its canonical name.
060 *
061 * @param name the canonical name
062 * @return the named type element, or {@code null} if it cannot be found
063 */
064 TypeElement getTypeElement(CharSequence name);
065
066 /**
067 * Returns the values of an annotation's elements, including defaults.
068 *
069 * @see AnnotationMirror#getElementValues()
070 * @param a annotation to examine
071 * @return the values of the annotation's elements, including defaults
072 */
073 Map<? extends ExecutableElement, ? extends AnnotationValue>
074 getElementValuesWithDefaults(AnnotationMirror a);
075
076 /**
077 * Returns the text of the documentation ("Javadoc")
078 * comment of an element.
079 *
080 * @param e the element being examined
081 * @return the documentation comment of the element, or {@code null}
082 * if there is none
083 */
084 String getDocComment(Element e);
085
086 /**
087 * Returns {@code true} if the element is deprecated, {@code false} otherwise.
088 *
089 * @param e the element being examined
090 * @return {@code true} if the element is deprecated, {@code false} otherwise
091 */
092 boolean isDeprecated(Element e);
093
094 /**
095 * Returns the <i>binary name</i> of a type element.
096 *
097 * @param type the type element being examined
098 * @return the binary name
099 *
100 * @see TypeElement#getQualifiedName
101 * @jls3 13.1 The Form of a Binary
102 */
103 Name getBinaryName(TypeElement type);
104
105
106 /**
107 * Returns the package of an element. The package of a package is
108 * itself.
109 *
110 * @param type the element being examined
111 * @return the package of an element
112 */
113 PackageElement getPackageOf(Element type);
114
115 /**
116 * Returns all members of a type element, whether inherited or
117 * declared directly. For a class the result also includes its
118 * constructors, but not local or anonymous classes.
119 *
120 * <p>Note that elements of certain kinds can be isolated using
121 * methods in {@link ElementFilter}.
122 *
123 * @param type the type being examined
124 * @return all members of the type
125 * @see Element#getEnclosedElements
126 */
127 List<? extends Element> getAllMembers(TypeElement type);
128
129 /**
130 * Returns all annotations of an element, whether
131 * inherited or directly present.
132 *
133 * @param e the element being examined
134 * @return all annotations of the element
135 * @see Element#getAnnotationMirrors
136 */
137 List<? extends AnnotationMirror> getAllAnnotationMirrors(Element e);
138
139 /**
140 * Tests whether one type, method, or field hides another.
141 *
142 * @param hider the first element
143 * @param hidden the second element
144 * @return {@code true} if and only if the first element hides
145 * the second
146 */
147 boolean hides(Element hider, Element hidden);
148
149 /**
150 * Tests whether one method, as a member of a given type,
151 * overrides another method.
152 * When a non-abstract method overrides an abstract one, the
153 * former is also said to <i>implement</i> the latter.
154 *
155 * <p> In the simplest and most typical usage, the value of the
156 * {@code type} parameter will simply be the class or interface
157 * directly enclosing {@code overrider} (the possibly-overriding
158 * method). For example, suppose {@code m1} represents the method
159 * {@code String.hashCode} and {@code m2} represents {@code
160 * Object.hashCode}. We can then ask whether {@code m1} overrides
161 * {@code m2} within the class {@code String} (it does):
162 *
163 * <blockquote>
164 * {@code assert elements.overrides(m1, m2,
165 * elements.getTypeElement("java.lang.String")); }
166 * </blockquote>
167 *
168 * A more interesting case can be illustrated by the following example
169 * in which a method in type {@code A} does not override a
170 * like-named method in type {@code B}:
171 *
172 * <blockquote>
173 * {@code class A { public void m() {} } }<br>
174 * {@code interface B { void m(); } }<br>
175 * ...<br>
176 * {@code m1 = ...; // A.m }<br>
177 * {@code m2 = ...; // B.m }<br>
178 * {@code assert ! elements.overrides(m1, m2,
179 * elements.getTypeElement("A")); }
180 * </blockquote>
181 *
182 * When viewed as a member of a third type {@code C}, however,
183 * the method in {@code A} does override the one in {@code B}:
184 *
185 * <blockquote>
186 * {@code class C extends A implements B {} }<br>
187 * ...<br>
188 * {@code assert elements.overrides(m1, m2,
189 * elements.getTypeElement("C")); }
190 * </blockquote>
191 *
192 * @param overrider the first method, possible overrider
193 * @param overridden the second method, possibly being overridden
194 * @param type the type of which the first method is a member
195 * @return {@code true} if and only if the first method overrides
196 * the second
197 * @jls3 8.4.8 Inheritance, Overriding, and Hiding
198 * @jls3 9.4.1 Inheritance and Overriding
199 */
200 boolean overrides(ExecutableElement overrider, ExecutableElement overridden,
201 TypeElement type);
202
203 /**
204 * Returns the text of a <i>constant expression</i> representing a
205 * primitive value or a string.
206 * The text returned is in a form suitable for representing the value
207 * in source code.
208 *
209 * @param value a primitive value or string
210 * @return the text of a constant expression
211 * @throws IllegalArgumentException if the argument is not a primitive
212 * value or string
213 *
214 * @see VariableElement#getConstantValue()
215 */
216 String getConstantExpression(Object value);
217
218 /**
219 * Prints a representation of the elements to the given writer in
220 * the specified order. The main purpose of this method is for
221 * diagnostics. The exact format of the output is <em>not</em>
222 * specified and is subject to change.
223 *
224 * @param w the writer to print the output to
225 * @param elements the elements to print
226 */
227 void printElements(java.io.Writer w, Element... elements);
228
229 /**
230 * Return a name with the same sequence of characters as the
231 * argument.
232 *
233 * @param cs the character sequence to return as a name
234 */
235 Name getName(CharSequence cs);
236 }