1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/classes/javax/lang/model/element/AnnotationValueVisitor.java Wed Apr 27 01:34:52 2016 +0800
1.3 @@ -0,0 +1,214 @@
1.4 +/*
1.5 + * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Oracle designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Oracle in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.25 + * or visit www.oracle.com if you need additional information or have any
1.26 + * questions.
1.27 + */
1.28 +
1.29 +package javax.lang.model.element;
1.30 +
1.31 +
1.32 +import java.util.List;
1.33 +
1.34 +import javax.lang.model.type.TypeMirror;
1.35 +
1.36 +
1.37 +/**
1.38 + * A visitor of the values of annotation type elements, using a
1.39 + * variant of the visitor design pattern. Unlike a standard visitor
1.40 + * which dispatches based on the concrete type of a member of a type
1.41 + * hierarchy, this visitor dispatches based on the type of data
1.42 + * stored; there are no distinct subclasses for storing, for example,
1.43 + * {@code boolean} values versus {@code int} values. Classes
1.44 + * implementing this interface are used to operate on a value when the
1.45 + * type of that value is unknown at compile time. When a visitor is
1.46 + * passed to a value's {@link AnnotationValue#accept accept} method,
1.47 + * the <tt>visit<i>XYZ</i></tt> method applicable to that value is
1.48 + * invoked.
1.49 + *
1.50 + * <p> Classes implementing this interface may or may not throw a
1.51 + * {@code NullPointerException} if the additional parameter {@code p}
1.52 + * is {@code null}; see documentation of the implementing class for
1.53 + * details.
1.54 + *
1.55 + * <p> <b>WARNING:</b> It is possible that methods will be added to
1.56 + * this interface to accommodate new, currently unknown, language
1.57 + * structures added to future versions of the Java™ programming
1.58 + * language. Therefore, visitor classes directly implementing this
1.59 + * interface may be source incompatible with future versions of the
1.60 + * platform. To avoid this source incompatibility, visitor
1.61 + * implementations are encouraged to instead extend the appropriate
1.62 + * abstract visitor class that implements this interface. However, an
1.63 + * API should generally use this visitor interface as the type for
1.64 + * parameters, return type, etc. rather than one of the abstract
1.65 + * classes.
1.66 + *
1.67 + * <p>Note that methods to accommodate new language constructs could
1.68 + * be added in a source <em>compatible</em> way if they were added as
1.69 + * <em>default methods</em>. However, default methods are only
1.70 + * available on Java SE 8 and higher releases and the {@code
1.71 + * javax.lang.model.*} packages bundled in Java SE 8 are required to
1.72 + * also be runnable on Java SE 7. Therefore, default methods
1.73 + * <em>cannot</em> be used when extending {@code javax.lang.model.*}
1.74 + * to cover Java SE 8 language features. However, default methods may
1.75 + * be used in subsequent revisions of the {@code javax.lang.model.*}
1.76 + * packages that are only required to run on Java SE 8 and higher
1.77 + * platform versions.
1.78 + *
1.79 + * @param <R> the return type of this visitor's methods
1.80 + * @param <P> the type of the additional parameter to this visitor's methods.
1.81 + * @author Joseph D. Darcy
1.82 + * @author Scott Seligman
1.83 + * @author Peter von der Ahé
1.84 + * @since 1.6
1.85 + */
1.86 +public interface AnnotationValueVisitor<R, P> {
1.87 + /**
1.88 + * Visits an annotation value.
1.89 + * @param av the value to visit
1.90 + * @param p a visitor-specified parameter
1.91 + * @return a visitor-specified result
1.92 + */
1.93 + R visit(AnnotationValue av, P p);
1.94 +
1.95 + /**
1.96 + * A convenience method equivalent to {@code v.visit(av, null)}.
1.97 + * @param av the value to visit
1.98 + * @return a visitor-specified result
1.99 + */
1.100 + R visit(AnnotationValue av);
1.101 +
1.102 + /**
1.103 + * Visits a {@code boolean} value in an annotation.
1.104 + * @param b the value being visited
1.105 + * @param p a visitor-specified parameter
1.106 + * @return the result of the visit
1.107 + */
1.108 + R visitBoolean(boolean b, P p);
1.109 +
1.110 + /**
1.111 + * Visits a {@code byte} value in an annotation.
1.112 + * @param b the value being visited
1.113 + * @param p a visitor-specified parameter
1.114 + * @return the result of the visit
1.115 + */
1.116 + R visitByte(byte b, P p);
1.117 +
1.118 + /**
1.119 + * Visits a {@code char} value in an annotation.
1.120 + * @param c the value being visited
1.121 + * @param p a visitor-specified parameter
1.122 + * @return the result of the visit
1.123 + */
1.124 + R visitChar(char c, P p);
1.125 +
1.126 + /**
1.127 + * Visits a {@code double} value in an annotation.
1.128 + * @param d the value being visited
1.129 + * @param p a visitor-specified parameter
1.130 + * @return the result of the visit
1.131 + */
1.132 + R visitDouble(double d, P p);
1.133 +
1.134 + /**
1.135 + * Visits a {@code float} value in an annotation.
1.136 + * @param f the value being visited
1.137 + * @param p a visitor-specified parameter
1.138 + * @return the result of the visit
1.139 + */
1.140 + R visitFloat(float f, P p);
1.141 +
1.142 + /**
1.143 + * Visits an {@code int} value in an annotation.
1.144 + * @param i the value being visited
1.145 + * @param p a visitor-specified parameter
1.146 + * @return the result of the visit
1.147 + */
1.148 + R visitInt(int i, P p);
1.149 +
1.150 + /**
1.151 + * Visits a {@code long} value in an annotation.
1.152 + * @param i the value being visited
1.153 + * @param p a visitor-specified parameter
1.154 + * @return the result of the visit
1.155 + */
1.156 + R visitLong(long i, P p);
1.157 +
1.158 + /**
1.159 + * Visits a {@code short} value in an annotation.
1.160 + * @param s the value being visited
1.161 + * @param p a visitor-specified parameter
1.162 + * @return the result of the visit
1.163 + */
1.164 + R visitShort(short s, P p);
1.165 +
1.166 + /**
1.167 + * Visits a string value in an annotation.
1.168 + * @param s the value being visited
1.169 + * @param p a visitor-specified parameter
1.170 + * @return the result of the visit
1.171 + */
1.172 + R visitString(String s, P p);
1.173 +
1.174 + /**
1.175 + * Visits a type value in an annotation.
1.176 + * @param t the value being visited
1.177 + * @param p a visitor-specified parameter
1.178 + * @return the result of the visit
1.179 + */
1.180 + R visitType(TypeMirror t, P p);
1.181 +
1.182 + /**
1.183 + * Visits an {@code enum} value in an annotation.
1.184 + * @param c the value being visited
1.185 + * @param p a visitor-specified parameter
1.186 + * @return the result of the visit
1.187 + */
1.188 + R visitEnumConstant(VariableElement c, P p);
1.189 +
1.190 + /**
1.191 + * Visits an annotation value in an annotation.
1.192 + * @param a the value being visited
1.193 + * @param p a visitor-specified parameter
1.194 + * @return the result of the visit
1.195 + */
1.196 + R visitAnnotation(AnnotationMirror a, P p);
1.197 +
1.198 + /**
1.199 + * Visits an array value in an annotation.
1.200 + * @param vals the value being visited
1.201 + * @param p a visitor-specified parameter
1.202 + * @return the result of the visit
1.203 + */
1.204 + R visitArray(List<? extends AnnotationValue> vals, P p);
1.205 +
1.206 + /**
1.207 + * Visits an unknown kind of annotation value.
1.208 + * This can occur if the language evolves and new kinds
1.209 + * of value can be stored in an annotation.
1.210 + * @param av the unknown value being visited
1.211 + * @param p a visitor-specified parameter
1.212 + * @return the result of the visit
1.213 + * @throws UnknownAnnotationValueException
1.214 + * a visitor implementation may optionally throw this exception
1.215 + */
1.216 + R visitUnknown(AnnotationValue av, P p);
1.217 +}
