1 /*
   2  * Copyright (c) 2012, 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 com.sun.tools.javac.code;
  27 
  28 
  29 import com.sun.tools.javac.code.Attribute.TypeCompound;
  30 import com.sun.tools.javac.code.Kinds.Kind;
  31 import com.sun.tools.javac.util.Assert;
  32 import com.sun.tools.javac.util.List;
  33 import com.sun.tools.javac.util.ListBuffer;
  34 
  35 /**
  36  * Container for all annotations (attributes in javac) on a Symbol.
  37  *
  38  * This class is explicitly mutable. Its contents will change when attributes
  39  * are annotated onto the Symbol. However this class depends on the facts that
  40  * List (in javac) is immutable.
  41  *
  42  * An instance of this class can be in one of three states:
  43  *
  44  * NOT_STARTED indicates that the Symbol this instance belongs to has not been
  45  * annotated (yet). Specifically if the declaration is not annotated this
  46  * instance will never move past NOT_STARTED. You can never go back to
  47  * NOT_STARTED.
  48  *
  49  * IN_PROGRESS annotations have been found on the declaration. Will be processed
  50  * later. You can reset to IN_PROGRESS. While IN_PROGRESS you can set the list
  51  * of attributes (and this moves out of the IN_PROGRESS state).
  52  *
  53  * "unnamed" this SymbolMetadata contains some attributes, possibly the final set.
  54  * While in this state you can only prepend or append to the attributes not set
  55  * it directly. You can also move back to the IN_PROGRESS state using reset().
  56  *
  57  * <p><b>This is NOT part of any supported API. If you write code that depends
  58  * on this, you do so at your own risk. This code and its internal interfaces
  59  * are subject to change or deletion without notice.</b>
  60  */
  61 public class SymbolMetadata {
  62 
  63     private static final List<Attribute.Compound> DECL_NOT_STARTED = List.of(null);
  64     private static final List<Attribute.Compound> DECL_IN_PROGRESS = List.of(null);
  65 
  66     /*
  67      * This field should never be null
  68      */
  69     private List<Attribute.Compound> attributes = DECL_NOT_STARTED;
  70 
  71     /*
  72      * Type attributes for this symbol.
  73      * This field should never be null.
  74      */
  75     private List<Attribute.TypeCompound> type_attributes = List.nil();
  76 
  77     /*
  78      * Type attributes of initializers in this class.
  79      * Unused if the current symbol is not a ClassSymbol.
  80      */
  81     private List<Attribute.TypeCompound> init_type_attributes = List.nil();
  82 
  83     /*
  84      * Type attributes of class initializers in this class.
  85      * Unused if the current symbol is not a ClassSymbol.
  86      */
  87     private List<Attribute.TypeCompound> clinit_type_attributes = List.nil();
  88 
  89     /*
  90      * The Symbol this SymbolMetadata instance belongs to
  91      */
  92     private final Symbol sym;
  93 
  94     public SymbolMetadata(Symbol sym) {
  95         this.sym = sym;
  96     }
  97 
  98     public List<Attribute.Compound> getDeclarationAttributes() {
  99         return filterDeclSentinels(attributes);
 100     }
 101 
 102     public List<Attribute.TypeCompound> getTypeAttributes() {
 103         return type_attributes;
 104     }
 105 
 106     public List<Attribute.TypeCompound> getInitTypeAttributes() {
 107         return init_type_attributes;
 108     }
 109 
 110     public List<Attribute.TypeCompound> getClassInitTypeAttributes() {
 111         return clinit_type_attributes;
 112     }
 113 
 114     public void setDeclarationAttributes(List<Attribute.Compound> a) {
 115         Assert.check(pendingCompletion() || !isStarted());
 116         if (a == null) {
 117             throw new NullPointerException();
 118         }
 119         attributes = a;
 120     }
 121 
 122     public void setTypeAttributes(List<Attribute.TypeCompound> a) {
 123         if (a == null) {
 124             throw new NullPointerException();
 125         }
 126         type_attributes = a;
 127     }
 128 
 129     public void setInitTypeAttributes(List<Attribute.TypeCompound> a) {
 130         if (a == null) {
 131             throw new NullPointerException();
 132         }
 133         init_type_attributes = a;
 134     }
 135 
 136     public void setClassInitTypeAttributes(List<Attribute.TypeCompound> a) {
 137         if (a == null) {
 138             throw new NullPointerException();
 139         }
 140         clinit_type_attributes = a;
 141     }
 142 
 143     public void setAttributes(SymbolMetadata other) {
 144         if (other == null) {
 145             throw new NullPointerException();
 146         }
 147         setDeclarationAttributes(other.getDeclarationAttributes());
 148         if ((sym.flags() & Flags.BRIDGE) != 0) {
 149             Assert.check(other.sym.kind == Kind.MTH);
 150             ListBuffer<TypeCompound> typeAttributes = new ListBuffer<>();
 151             for (TypeCompound tc : other.getTypeAttributes()) {
 152                 // Carry over only contractual type annotations: i.e nothing interior to method body.
 153                 if (!tc.position.type.isLocal())
 154                     typeAttributes.append(tc);
 155             }
 156             setTypeAttributes(typeAttributes.toList());
 157         } else {
 158             setTypeAttributes(other.getTypeAttributes());
 159         }
 160         if (sym.kind == Kind.TYP) {
 161             setInitTypeAttributes(other.getInitTypeAttributes());
 162             setClassInitTypeAttributes(other.getClassInitTypeAttributes());
 163         }
 164     }
 165 
 166     public SymbolMetadata reset() {
 167         attributes = DECL_IN_PROGRESS;
 168         return this;
 169     }
 170 
 171     public boolean isEmpty() {
 172         return !isStarted()
 173                 || pendingCompletion()
 174                 || attributes.isEmpty();
 175     }
 176 
 177     public boolean isTypesEmpty() {
 178         return type_attributes.isEmpty();
 179     }
 180 
 181     public boolean pendingCompletion() {
 182         return attributes == DECL_IN_PROGRESS;
 183     }
 184 
 185     public SymbolMetadata append(List<Attribute.Compound> l) {
 186         attributes = filterDeclSentinels(attributes);
 187 
 188         if (l.isEmpty()) {
 189             // no-op
 190         } else if (attributes.isEmpty()) {
 191             attributes = l;
 192         } else {
 193             attributes = attributes.appendList(l);
 194         }
 195         return this;
 196     }
 197 
 198     public SymbolMetadata appendUniqueTypes(List<Attribute.TypeCompound> l) {
 199         if (l.isEmpty()) {
 200             // no-op
 201         } else if (type_attributes.isEmpty()) {
 202             type_attributes = l;
 203         } else {
 204             // TODO: in case we expect a large number of annotations, this
 205             // might be inefficient.
 206             for (Attribute.TypeCompound tc : l) {
 207                 if (!type_attributes.contains(tc))
 208                     type_attributes = type_attributes.append(tc);
 209             }
 210         }
 211         return this;
 212     }
 213 
 214     public SymbolMetadata appendInitTypeAttributes(List<Attribute.TypeCompound> l) {
 215         if (l.isEmpty()) {
 216             // no-op
 217         } else if (init_type_attributes.isEmpty()) {
 218             init_type_attributes = l;
 219         } else {
 220             init_type_attributes = init_type_attributes.appendList(l);
 221         }
 222         return this;
 223     }
 224 
 225     public SymbolMetadata appendClassInitTypeAttributes(List<Attribute.TypeCompound> l) {
 226         if (l.isEmpty()) {
 227             // no-op
 228         } else if (clinit_type_attributes.isEmpty()) {
 229             clinit_type_attributes = l;
 230         } else {
 231             clinit_type_attributes = clinit_type_attributes.appendList(l);
 232         }
 233         return this;
 234     }
 235 
 236     public SymbolMetadata prepend(List<Attribute.Compound> l) {
 237         attributes = filterDeclSentinels(attributes);
 238 
 239         if (l.isEmpty()) {
 240             // no-op
 241         } else if (attributes.isEmpty()) {
 242             attributes = l;
 243         } else {
 244             attributes = attributes.prependList(l);
 245         }
 246         return this;
 247     }
 248 
 249     private List<Attribute.Compound> filterDeclSentinels(List<Attribute.Compound> a) {
 250         return (a == DECL_IN_PROGRESS || a == DECL_NOT_STARTED)
 251                 ? List.nil()
 252                 : a;
 253     }
 254 
 255     private boolean isStarted() {
 256         return attributes != DECL_NOT_STARTED;
 257     }
 258 
 259     private List<Attribute.Compound> removeFromCompoundList(List<Attribute.Compound> l, Attribute.Compound compound) {
 260         ListBuffer<Attribute.Compound> lb = new ListBuffer<>();
 261         for (Attribute.Compound c : l) {
 262             if (c != compound) {
 263                 lb.add(c);
 264             }
 265         }
 266         return lb.toList();
 267     }
 268 
 269     private List<Attribute.TypeCompound> removeFromTypeCompoundList(List<Attribute.TypeCompound> l, Attribute.TypeCompound compound) {
 270         ListBuffer<Attribute.TypeCompound> lb = new ListBuffer<>();
 271         for (Attribute.TypeCompound c : l) {
 272             if (c != compound) {
 273                 lb.add(c);
 274             }
 275         }
 276         return lb.toList();
 277     }
 278 
 279     public void remove(Attribute.Compound compound) {
 280         if (attributes.contains(compound)) {
 281             attributes = removeFromCompoundList(attributes, compound);
 282         } else if (type_attributes.contains(compound)) {
 283             type_attributes = removeFromTypeCompoundList(type_attributes, (TypeCompound)compound);
 284         } else if (init_type_attributes.contains(compound)) {
 285             init_type_attributes = removeFromTypeCompoundList(init_type_attributes, (TypeCompound)compound);
 286         } else if (clinit_type_attributes.contains(compound)) {
 287             clinit_type_attributes = removeFromTypeCompoundList(clinit_type_attributes, (TypeCompound)compound);
 288         }
 289     }
 290 }