1 /*
   2  * Copyright (c) 2005, 2013, 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.lang.model.util;
  27 
  28 import javax.annotation.processing.SupportedSourceVersion;
  29 import javax.lang.model.SourceVersion;
  30 import javax.lang.model.type.*;
  31 import static javax.lang.model.SourceVersion.*;
  32 
  33 /**
  34  * A visitor of types based on their {@linkplain TypeKind kind} with
  35  * default behavior appropriate for the {@link SourceVersion#RELEASE_6
  36  * RELEASE_6} source version.  For {@linkplain
  37  * TypeMirror types} <tt><i>XYZ</i></tt> that may have more than one
  38  * kind, the <tt>visit<i>XYZ</i></tt> methods in this class delegate
  39  * to the <tt>visit<i>XYZKind</i></tt> method corresponding to the
  40  * first argument's kind.  The <tt>visit<i>XYZKind</i></tt> methods
  41  * call {@link #defaultAction defaultAction}, passing their arguments
  42  * to {@code defaultAction}'s corresponding parameters.
  43  *
  44  * <p> Methods in this class may be overridden subject to their
  45  * general contract.  Note that annotating methods in concrete
  46  * subclasses with {@link java.lang.Override @Override} will help
  47  * ensure that methods are overridden as intended.
  48  *
  49  * <p> <b>WARNING:</b> The {@code TypeVisitor} interface implemented
  50  * by this class may have methods added to it in the future to
  51  * accommodate new, currently unknown, language structures added to
  52  * future versions of the Java&trade; programming language.
  53  * Therefore, methods whose names begin with {@code "visit"} may be
  54  * added to this class in the future; to avoid incompatibilities,
  55  * classes which extend this class should not declare any instance
  56  * methods with names beginning with {@code "visit"}.
  57  *
  58  * <p>When such a new visit method is added, the default
  59  * implementation in this class will be to call the {@link
  60  * #visitUnknown visitUnknown} method.  A new type kind visitor class
  61  * will also be introduced to correspond to the new language level;
  62  * this visitor will have different default behavior for the visit
  63  * method in question.  When the new visitor is introduced, all or
  64  * portions of this visitor may be deprecated.
  65  *
  66  * <p>Note that adding a default implementation of a new visit method
  67  * in a visitor class will occur instead of adding a <em>default
  68  * method</em> directly in the visitor interface since a Java SE 8
  69  * language feature cannot be used to this version of the API since
  70  * this version is required to be runnable on Java SE 7
  71  * implementations.  Future versions of the API that are only required
  72  * to run on Java SE 8 and later may take advantage of default methods
  73  * in this situation.
  74  *
  75  * @param <R> the return type of this visitor's methods.  Use {@link
  76  *            Void} for visitors that do not need to return results.
  77  * @param <P> the type of the additional parameter to this visitor's
  78  *            methods.  Use {@code Void} for visitors that do not need an
  79  *            additional parameter.
  80  *
  81  * @author Joseph D. Darcy
  82  * @author Scott Seligman
  83  * @author Peter von der Ah&eacute;
  84  *
  85  * @see TypeKindVisitor7
  86  * @see TypeKindVisitor8
  87  * @since 1.6
  88  * @deprecated Release 6 is obsolete; update to a visitor for a newer
  89  * release level.
  90  */
  91 @Deprecated
  92 @SupportedSourceVersion(RELEASE_6)
  93 public class TypeKindVisitor6<R, P> extends SimpleTypeVisitor6<R, P> {
  94     /**
  95      * Constructor for concrete subclasses to call; uses {@code null}
  96      * for the default value.
  97      */
  98     protected TypeKindVisitor6() {
  99         super(null);
 100     }
 101 
 102 
 103     /**
 104      * Constructor for concrete subclasses to call; uses the argument
 105      * for the default value.
 106      *
 107      * @param defaultValue the value to assign to {@link #DEFAULT_VALUE}
 108      */
 109     protected TypeKindVisitor6(R defaultValue) {
 110         super(defaultValue);
 111     }
 112 
 113     /**
 114      * Visits a primitive type, dispatching to the visit method for
 115      * the specific {@linkplain TypeKind kind} of primitive type:
 116      * {@code BOOLEAN}, {@code BYTE}, etc.
 117      *
 118      * @param t {@inheritDoc}
 119      * @param p {@inheritDoc}
 120      * @return  the result of the kind-specific visit method
 121      */
 122     @Override
 123     public R visitPrimitive(PrimitiveType t, P p) {
 124         TypeKind k = t.getKind();
 125         switch (k) {
 126         case BOOLEAN:
 127             return visitPrimitiveAsBoolean(t, p);
 128 
 129         case BYTE:
 130             return visitPrimitiveAsByte(t, p);
 131 
 132         case SHORT:
 133             return visitPrimitiveAsShort(t, p);
 134 
 135         case INT:
 136             return visitPrimitiveAsInt(t, p);
 137 
 138         case LONG:
 139             return visitPrimitiveAsLong(t, p);
 140 
 141         case CHAR:
 142             return visitPrimitiveAsChar(t, p);
 143 
 144         case FLOAT:
 145             return visitPrimitiveAsFloat(t, p);
 146 
 147         case DOUBLE:
 148             return visitPrimitiveAsDouble(t, p);
 149 
 150         default:
 151             throw new AssertionError("Bad kind " + k + " for PrimitiveType" + t);
 152         }
 153     }
 154 
 155     /**
 156      * Visits a {@code BOOLEAN} primitive type by calling
 157      * {@code defaultAction}.
 158      *
 159      * @param t the type to visit
 160      * @param p a visitor-specified parameter
 161      * @return  the result of {@code defaultAction}
 162      */
 163     public R visitPrimitiveAsBoolean(PrimitiveType t, P p) {
 164         return defaultAction(t, p);
 165     }
 166 
 167     /**
 168      * Visits a {@code BYTE} primitive type by calling
 169      * {@code defaultAction}.
 170      *
 171      * @param t the type to visit
 172      * @param p a visitor-specified parameter
 173      * @return  the result of {@code defaultAction}
 174      */
 175     public R visitPrimitiveAsByte(PrimitiveType t, P p) {
 176         return defaultAction(t, p);
 177     }
 178 
 179     /**
 180      * Visits a {@code SHORT} primitive type by calling
 181      * {@code defaultAction}.
 182      *
 183      * @param t the type to visit
 184      * @param p a visitor-specified parameter
 185      * @return  the result of {@code defaultAction}
 186      */
 187     public R visitPrimitiveAsShort(PrimitiveType t, P p) {
 188         return defaultAction(t, p);
 189     }
 190 
 191     /**
 192      * Visits an {@code INT} primitive type by calling
 193      * {@code defaultAction}.
 194      *
 195      * @param t the type to visit
 196      * @param p a visitor-specified parameter
 197      * @return  the result of {@code defaultAction}
 198      */
 199     public R visitPrimitiveAsInt(PrimitiveType t, P p) {
 200         return defaultAction(t, p);
 201     }
 202 
 203     /**
 204      * Visits a {@code LONG} primitive type by calling
 205      * {@code defaultAction}.
 206      *
 207      * @param t the type to visit
 208      * @param p a visitor-specified parameter
 209      * @return  the result of {@code defaultAction}
 210      */
 211     public R visitPrimitiveAsLong(PrimitiveType t, P p) {
 212         return defaultAction(t, p);
 213     }
 214 
 215     /**
 216      * Visits a {@code CHAR} primitive type by calling
 217      * {@code defaultAction}.
 218      *
 219      * @param t the type to visit
 220      * @param p a visitor-specified parameter
 221      * @return  the result of {@code defaultAction}
 222      */
 223     public R visitPrimitiveAsChar(PrimitiveType t, P p) {
 224         return defaultAction(t, p);
 225     }
 226 
 227     /**
 228      * Visits a {@code FLOAT} primitive type by calling
 229      * {@code defaultAction}.
 230      *
 231      * @param t the type to visit
 232      * @param p a visitor-specified parameter
 233      * @return  the result of {@code defaultAction}
 234      */
 235     public R visitPrimitiveAsFloat(PrimitiveType t, P p) {
 236         return defaultAction(t, p);
 237     }
 238 
 239     /**
 240      * Visits a {@code DOUBLE} primitive type by calling
 241      * {@code defaultAction}.
 242      *
 243      * @param t the type to visit
 244      * @param p a visitor-specified parameter
 245      * @return  the result of {@code defaultAction}
 246      */
 247     public R visitPrimitiveAsDouble(PrimitiveType t, P p) {
 248         return defaultAction(t, p);
 249     }
 250 
 251     /**
 252      * Visits a {@link NoType} instance, dispatching to the visit method for
 253      * the specific {@linkplain TypeKind kind} of pseudo-type:
 254      * {@code VOID}, {@code PACKAGE}, or {@code NONE}.
 255      *
 256      * @param t {@inheritDoc}
 257      * @param p {@inheritDoc}
 258      * @return  the result of the kind-specific visit method
 259      */
 260     @Override
 261     public R visitNoType(NoType t, P p) {
 262         TypeKind k = t.getKind();
 263         switch (k) {
 264         case VOID:
 265             return visitNoTypeAsVoid(t, p);
 266 
 267         case PACKAGE:
 268             return visitNoTypeAsPackage(t, p);
 269 
 270         case NONE:
 271             return visitNoTypeAsNone(t, p);
 272 
 273         default:
 274             throw new AssertionError("Bad kind " + k + " for NoType" + t);
 275         }
 276     }
 277 
 278     /**
 279      * Visits a {@link TypeKind#VOID VOID} pseudo-type by calling
 280      * {@code defaultAction}.
 281      *
 282      * @param t the type to visit
 283      * @param p a visitor-specified parameter
 284      * @return  the result of {@code defaultAction}
 285      */
 286     public R visitNoTypeAsVoid(NoType t, P p) {
 287         return defaultAction(t, p);
 288     }
 289 
 290     /**
 291      * Visits a {@link TypeKind#PACKAGE PACKAGE} pseudo-type by calling
 292      * {@code defaultAction}.
 293      *
 294      * @param t the type to visit
 295      * @param p a visitor-specified parameter
 296      * @return  the result of {@code defaultAction}
 297      */
 298     public R visitNoTypeAsPackage(NoType t, P p) {
 299         return defaultAction(t, p);
 300     }
 301 
 302     /**
 303      * Visits a {@link TypeKind#NONE NONE} pseudo-type by calling
 304      * {@code defaultAction}.
 305      *
 306      * @param t the type to visit
 307      * @param p a visitor-specified parameter
 308      * @return  the result of {@code defaultAction}
 309      */
 310     public R visitNoTypeAsNone(NoType t, P p) {
 311         return defaultAction(t, p);
 312     }
 313 }