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1   /*
2    * Copyright (c) 2009, 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  import java.util.Locale;
29  
30  import com.sun.tools.javac.api.Messages;
31  import com.sun.tools.javac.code.Type.AnnotatedType;
32  import com.sun.tools.javac.code.Type.ArrayType;
33  import com.sun.tools.javac.code.Symbol.*;
34  import com.sun.tools.javac.code.Type.*;
35  import com.sun.tools.javac.util.List;
36  import com.sun.tools.javac.util.ListBuffer;
37  
38  import static com.sun.tools.javac.code.BoundKind.*;
39  import static com.sun.tools.javac.code.Flags.*;
40  import static com.sun.tools.javac.code.TypeTag.CLASS;
41  import static com.sun.tools.javac.code.TypeTag.FORALL;
42  
43  /**
44   * A combined type/symbol visitor for generating non-trivial localized string
45   * representation of types and symbols.
46   *
47   * <p><b>This is NOT part of any supported API.
48   * If you write code that depends on this, you do so at your own risk.
49   * This code and its internal interfaces are subject to change or
50   * deletion without notice.</b>
51   */
52  public abstract class Printer implements Type.Visitor<String, Locale>, Symbol.Visitor<String, Locale> {
53  
54      List<Type> seenCaptured = List.nil();
55      static final int PRIME = 997;  // largest prime less than 1000
56  
57      protected Printer() { }
58  
59      /**
60       * This method should be overriden in order to provide proper i18n support.
61       *
62       * @param locale the locale in which the string is to be rendered
63       * @param key the key corresponding to the message to be displayed
64       * @param args a list of optional arguments
65       * @return localized string representation
66       */
67      protected abstract String localize(Locale locale, String key, Object... args);
68  
69      /**
70       * Maps a captured type into an unique identifier.
71       *
72       * @param t the captured type for which an id is to be retrieved
73       * @param locale locale settings
74       * @return unique id representing this captured type
75       */
76      protected abstract String capturedVarId(CapturedType t, Locale locale);
77  
78      /**
79       * Create a printer with default i18n support provided by Messages. By default,
80       * captured types ids are generated using hashcode.
81       *
82       * @param messages Messages class to be used for i18n
83       * @return printer visitor instance
84       */
85      public static Printer createStandardPrinter(final Messages messages) {
86          return new Printer() {
87              @Override
88              protected String localize(Locale locale, String key, Object... args) {
89                  return messages.getLocalizedString(locale, key, args);
90              }
91  
92              @Override
93              protected String capturedVarId(CapturedType t, Locale locale) {
94                  return (t.hashCode() & 0xFFFFFFFFL) % PRIME + "";
95          }};
96      }
97  
98      /**
99       * Get a localized string representation for all the types in the input list.
100      *
101      * @param ts types to be displayed
102      * @param locale the locale in which the string is to be rendered
103      * @return localized string representation
104      */
105     public String visitTypes(List<Type> ts, Locale locale) {
106         ListBuffer<String> sbuf = new ListBuffer<>();
107         for (Type t : ts) {
108             sbuf.append(visit(t, locale));
109         }
110         return sbuf.toList().toString();
111     }
112 
113     /**
114      * * Get a localized string representation for all the symbols in the input list.
115      *
116      * @param ts symbols to be displayed
117      * @param locale the locale in which the string is to be rendered
118      * @return localized string representation
119      */
120     public String visitSymbols(List<Symbol> ts, Locale locale) {
121         ListBuffer<String> sbuf = new ListBuffer<>();
122         for (Symbol t : ts) {
123             sbuf.append(visit(t, locale));
124         }
125         return sbuf.toList().toString();
126     }
127 
128     /**
129      * Get a localized string representation for a given type.
130      *
131      * @param t type to be displayed
132      * @param locale the locale in which the string is to be rendered
133      * @return localized string representation
134      */
135     public String visit(Type t, Locale locale) {
136         return t.accept(this, locale);
137     }
138 
139     /**
140      * Get a localized string representation for a given symbol.
141      *
142      * @param s symbol to be displayed
143      * @param locale the locale in which the string is to be rendered
144      * @return localized string representation
145      */
146     public String visit(Symbol s, Locale locale) {
147         return s.accept(this, locale);
148     }
149 
150     @Override
151     public String visitCapturedType(CapturedType t, Locale locale) {
152         if (seenCaptured.contains(t))
153             return localize(locale, "compiler.misc.type.captureof.1",
154                 capturedVarId(t, locale));
155         else {
156             try {
157                 seenCaptured = seenCaptured.prepend(t);
158                 return localize(locale, "compiler.misc.type.captureof",
159                     capturedVarId(t, locale),
160                     visit(t.wildcard, locale));
161             }
162             finally {
163                 seenCaptured = seenCaptured.tail;
164             }
165         }
166     }
167 
168     @Override
169     public String visitForAll(ForAll t, Locale locale) {
170         return "<" + visitTypes(t.tvars, locale) + ">" + visit(t.qtype, locale);
171     }
172 
173     @Override
174     public String visitUndetVar(UndetVar t, Locale locale) {
175         if (t.inst != null) {
176             return visit(t.inst, locale);
177         } else {
178             return visit(t.qtype, locale) + "?";
179         }
180     }
181 
182     @Override
183     public String visitArrayType(ArrayType t, Locale locale) {
184         StringBuilder res = new StringBuilder();
185         printBaseElementType(t, res, locale);
186         printBrackets(t, res, locale);
187         return res.toString();
188     }
189 
190     void printBaseElementType(Type t, StringBuilder sb, Locale locale) {
191         Type arrel = t;
192         while (arrel.hasTag(TypeTag.ARRAY)) {
193             arrel = arrel.unannotatedType();
194             arrel = ((ArrayType) arrel).elemtype;
195         }
196         sb.append(visit(arrel, locale));
197     }
198 
199     void printBrackets(Type t, StringBuilder sb, Locale locale) {
200         Type arrel = t;
201         while (arrel.hasTag(TypeTag.ARRAY)) {
202             if (arrel.isAnnotated()) {
203                 sb.append(' ');
204                 sb.append(arrel.getAnnotationMirrors());
205                 sb.append(' ');
206             }
207             sb.append("[]");
208             arrel = arrel.unannotatedType();
209             arrel = ((ArrayType) arrel).elemtype;
210         }
211     }
212 
213     @Override
214     public String visitClassType(ClassType t, Locale locale) {
215         StringBuilder buf = new StringBuilder();
216         if (t.getEnclosingType().hasTag(CLASS) && t.tsym.owner.kind == Kinds.TYP) {
217             buf.append(visit(t.getEnclosingType(), locale));
218             buf.append('.');
219             buf.append(className(t, false, locale));
220         } else {
221             buf.append(className(t, true, locale));
222         }
223         if (t.getTypeArguments().nonEmpty()) {
224             buf.append('<');
225             buf.append(visitTypes(t.getTypeArguments(), locale));
226             buf.append('>');
227         }
228         return buf.toString();
229     }
230 
231     @Override
232     public String visitMethodType(MethodType t, Locale locale) {
233         return "(" + printMethodArgs(t.argtypes, false, locale) + ")" + visit(t.restype, locale);
234     }
235 
236     @Override
237     public String visitPackageType(PackageType t, Locale locale) {
238         return t.tsym.getQualifiedName().toString();
239     }
240 
241     @Override
242     public String visitWildcardType(WildcardType t, Locale locale) {
243         StringBuilder s = new StringBuilder();
244         s.append(t.kind);
245         if (t.kind != UNBOUND) {
246             s.append(visit(t.type, locale));
247         }
248         return s.toString();
249     }
250 
251     @Override
252     public String visitErrorType(ErrorType t, Locale locale) {
253         return visitType(t, locale);
254     }
255 
256     @Override
257     public String visitTypeVar(TypeVar t, Locale locale) {
258         return visitType(t, locale);
259     }
260 
261     @Override
262     public String visitAnnotatedType(AnnotatedType t, Locale locale) {
263         if (t.getAnnotationMirrors().nonEmpty()) {
264             if (t.unannotatedType().hasTag(TypeTag.ARRAY)) {
265                 StringBuilder res = new StringBuilder();
266                 printBaseElementType(t, res, locale);
267                 printBrackets(t, res, locale);
268                 return res.toString();
269             } else if (t.unannotatedType().hasTag(TypeTag.CLASS) &&
270                     t.unannotatedType().getEnclosingType() != Type.noType) {
271                 return visit(t.unannotatedType().getEnclosingType(), locale) +
272                         ". " +
273                         t.getAnnotationMirrors() +
274                         " " + className((ClassType)t.unannotatedType(), false, locale);
275             } else {
276                 return t.getAnnotationMirrors() + " " + visit(t.unannotatedType(), locale);
277             }
278         } else {
279             return visit(t.unannotatedType(), locale);
280         }
281     }
282 
283     public String visitType(Type t, Locale locale) {
284         String s = (t.tsym == null || t.tsym.name == null)
285                 ? localize(locale, "compiler.misc.type.none")
286                 : t.tsym.name.toString();
287         return s;
288     }
289 
290     /**
291      * Converts a class name into a (possibly localized) string. Anonymous
292      * inner classes get converted into a localized string.
293      *
294      * @param t the type of the class whose name is to be rendered
295      * @param longform if set, the class' fullname is displayed - if unset the
296      * short name is chosen (w/o package)
297      * @param locale the locale in which the string is to be rendered
298      * @return localized string representation
299      */
300     protected String className(ClassType t, boolean longform, Locale locale) {
301         Symbol sym = t.tsym;
302         if (sym.name.length() == 0 && (sym.flags() & COMPOUND) != 0) {
303             StringBuilder s = new StringBuilder(visit(t.supertype_field, locale));
304             for (List<Type> is = t.interfaces_field; is.nonEmpty(); is = is.tail) {
305                 s.append('&');
306                 s.append(visit(is.head, locale));
307             }
308             return s.toString();
309         } else if (sym.name.length() == 0) {
310             String s;
311             ClassType norm = (ClassType) t.tsym.type;
312             if (norm == null) {
313                 s = localize(locale, "compiler.misc.anonymous.class", (Object) null);
314             } else if (norm.interfaces_field != null && norm.interfaces_field.nonEmpty()) {
315                 s = localize(locale, "compiler.misc.anonymous.class",
316                         visit(norm.interfaces_field.head, locale));
317             } else {
318                 s = localize(locale, "compiler.misc.anonymous.class",
319                         visit(norm.supertype_field, locale));
320             }
321             return s;
322         } else if (longform) {
323             return sym.getQualifiedName().toString();
324         } else {
325             return sym.name.toString();
326         }
327     }
328 
329     /**
330      * Converts a set of method argument types into their corresponding
331      * localized string representation.
332      *
333      * @param args arguments to be rendered
334      * @param varArgs if true, the last method argument is regarded as a vararg
335      * @param locale the locale in which the string is to be rendered
336      * @return localized string representation
337      */
338     protected String printMethodArgs(List<Type> args, boolean varArgs, Locale locale) {
339         if (!varArgs) {
340             return visitTypes(args, locale);
341         } else {
342             StringBuilder buf = new StringBuilder();
343             while (args.tail.nonEmpty()) {
344                 buf.append(visit(args.head, locale));
345                 args = args.tail;
346                 buf.append(',');
347             }
348             if (args.head.unannotatedType().hasTag(TypeTag.ARRAY)) {
349                 buf.append(visit(((ArrayType) args.head.unannotatedType()).elemtype, locale));
350                 if (args.head.getAnnotationMirrors().nonEmpty()) {
351                     buf.append(' ');
352                     buf.append(args.head.getAnnotationMirrors());
353                     buf.append(' ');
354                 }
355                 buf.append("...");
356             } else {
357                 buf.append(visit(args.head, locale));
358             }
359             return buf.toString();
360         }
361     }
362 
363     @Override
364     public String visitClassSymbol(ClassSymbol sym, Locale locale) {
365         return sym.name.isEmpty()
366                 ? localize(locale, "compiler.misc.anonymous.class", sym.flatname)
367                 : sym.fullname.toString();
368     }
369 
370     @Override
371     public String visitMethodSymbol(MethodSymbol s, Locale locale) {
372         if (s.isStaticOrInstanceInit()) {
373             return s.owner.name.toString();
374         } else {
375             String ms = (s.name == s.name.table.names.init)
376                     ? s.owner.name.toString()
377                     : s.name.toString();
378             if (s.type != null) {
379                 if (s.type.hasTag(FORALL)) {
380                     ms = "<" + visitTypes(s.type.getTypeArguments(), locale) + ">" + ms;
381                 }
382                 ms += "(" + printMethodArgs(
383                         s.type.getParameterTypes(),
384                         (s.flags() & VARARGS) != 0,
385                         locale) + ")";
386             }
387             return ms;
388         }
389     }
390 
391     @Override
392     public String visitOperatorSymbol(OperatorSymbol s, Locale locale) {
393         return visitMethodSymbol(s, locale);
394     }
395 
396     @Override
397     public String visitPackageSymbol(PackageSymbol s, Locale locale) {
398         return s.isUnnamed()
399                 ? localize(locale, "compiler.misc.unnamed.package")
400                 : s.fullname.toString();
401     }
402 
403     @Override
404     public String visitTypeSymbol(TypeSymbol s, Locale locale) {
405         return visitSymbol(s, locale);
406     }
407 
408     @Override
409     public String visitVarSymbol(VarSymbol s, Locale locale) {
410         return visitSymbol(s, locale);
411     }
412 
413     @Override
414     public String visitSymbol(Symbol s, Locale locale) {
415         return s.name.toString();
416     }
417 }