1 /*
  2  * Copyright (c) 2009, 2019, 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.ArrayType;
 32 import com.sun.tools.javac.code.Symbol.*;
 33 import com.sun.tools.javac.code.Type.*;
 34 import com.sun.tools.javac.util.List;
 35 import com.sun.tools.javac.util.ListBuffer;
 36 
 37 import static com.sun.tools.javac.code.BoundKind.*;
 38 import static com.sun.tools.javac.code.Flags.*;
 39 import static com.sun.tools.javac.code.Kinds.Kind.*;
 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 overridden 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 printAnnotations(t) +
154                 localize(locale, "compiler.misc.type.captureof.1",
155                 capturedVarId(t, locale));
156         else {
157             try {
158                 seenCaptured = seenCaptured.prepend(t);
159                 return printAnnotations(t) +
160                     localize(locale, "compiler.misc.type.captureof",
161                     capturedVarId(t, locale),
162                     visit(t.wildcard, locale));
163             }
164             finally {
165                 seenCaptured = seenCaptured.tail;
166             }
167         }
168     }
169 
170     @Override
171     public String visitForAll(ForAll t, Locale locale) {
172         return printAnnotations(t) + "<" + visitTypes(t.tvars, locale) +
173             ">" + visit(t.qtype, locale);
174     }
175 
176     @Override
177     public String visitUndetVar(UndetVar t, Locale locale) {
178         if (t.getInst() != null) {
179             return printAnnotations(t) + visit(t.getInst(), locale);
180         } else {
181             return printAnnotations(t) + visit(t.qtype, locale) + "?";
182         }
183     }
184 
185     @Override
186     public String visitArrayType(ArrayType t, Locale locale) {
187         StringBuilder res = new StringBuilder();
188         printBaseElementType(t, res, locale);
189         printBrackets(t, res, locale);
190         return res.toString();
191     }
192 
193     private String printAnnotations(Type t) {
194         return printAnnotations(t, false);
195     }
196 
197     private String printAnnotations(Type t, boolean prefix) {
198         StringBuilder sb = new StringBuilder();
199         List<Attribute.TypeCompound> annos = t.getAnnotationMirrors();
200         if (!annos.isEmpty()) {
201             if (prefix) sb.append(' ');
202             sb.append(annos);
203             sb.append(' ');
204         }
205         return sb.toString();
206     }
207 
208     private void printBaseElementType(Type t, StringBuilder sb, Locale locale) {
209         Type arrel = t;
210         while (arrel.hasTag(TypeTag.ARRAY)) {
211             arrel = ((ArrayType) arrel).elemtype;
212         }
213         sb.append(visit(arrel, locale));
214     }
215 
216     private void printBrackets(Type t, StringBuilder sb, Locale locale) {
217         Type arrel = t;
218         while (arrel.hasTag(TypeTag.ARRAY)) {
219             sb.append(printAnnotations(arrel, true));
220             sb.append("[]");
221             arrel = ((ArrayType) arrel).elemtype;
222         }
223     }
224 
225     @Override
226     public String visitClassType(ClassType t, Locale locale) {
227         StringBuilder buf = new StringBuilder();
228         if (t.getEnclosingType().hasTag(CLASS) && t.tsym.owner.kind == TYP) {
229             buf.append(visit(t.getEnclosingType(), locale));
230             buf.append('.');
231             buf.append(printAnnotations(t));
232             buf.append(className(t, false, locale));
233         } else {
234             buf.append(printAnnotations(t));
235             buf.append(className(t, true, locale));
236         }
237         boolean isReferenceProjection;
238         try {
239             isReferenceProjection = t.isReferenceProjection();
240         } catch (CompletionFailure cf) {
241             isReferenceProjection = false; // handle missing types gracefully.
242         }
243         if (isReferenceProjection) {
244             buf.append('.');
245             buf.append(t.tsym.name.table.names.ref);
246         }
247         if (t.getTypeArguments().nonEmpty()) {
248             buf.append('<');
249             buf.append(visitTypes(t.getTypeArguments(), locale));
250             buf.append('>');
251         }
252         return buf.toString();
253     }
254 
255     @Override
256     public String visitMethodType(MethodType t, Locale locale) {
257         return "(" + printMethodArgs(t.argtypes, false, locale) + ")" +
258             visit(t.restype, locale);
259     }
260 
261     @Override
262     public String visitPackageType(PackageType t, Locale locale) {
263         return t.tsym.getQualifiedName().toString();
264     }
265 
266     @Override
267     public String visitWildcardType(WildcardType t, Locale locale) {
268         StringBuilder s = new StringBuilder();
269         s.append(t.kind);
270         if (t.kind != UNBOUND) {
271             s.append(printAnnotations(t));
272             s.append(visit(t.type, locale));
273         }
274         return s.toString();
275     }
276 
277     @Override
278     public String visitErrorType(ErrorType t, Locale locale) {
279         return visitType(t, locale);
280     }
281 
282     @Override
283     public String visitTypeVar(TypeVar t, Locale locale) {
284         return visitType(t, locale);
285     }
286 
287     @Override
288     public String visitModuleType(ModuleType t, Locale locale) {
289         return visitType(t, locale);
290     }
291 
292     public String visitType(Type t, Locale locale) {
293         String s = (t.tsym == null || t.tsym.name == null)
294                 ? localize(locale, "compiler.misc.type.none")
295                 : t.tsym.name.toString();
296         return s;
297     }
298 
299     /**
300      * Converts a class name into a (possibly localized) string. Anonymous
301      * inner classes get converted into a localized string.
302      *
303      * @param t the type of the class whose name is to be rendered
304      * @param longform if set, the class' fullname is displayed - if unset the
305      * short name is chosen (w/o package)
306      * @param locale the locale in which the string is to be rendered
307      * @return localized string representation
308      */
309     protected String className(ClassType t, boolean longform, Locale locale) {
310         Symbol sym = t.tsym;
311         if (sym.name.length() == 0 && (sym.flags() & COMPOUND) != 0) {
312             StringBuilder s = new StringBuilder(visit(t.supertype_field, locale));
313             for (List<Type> is = t.interfaces_field; is.nonEmpty(); is = is.tail) {
314                 s.append('&');
315                 s.append(visit(is.head, locale));
316             }
317             return s.toString();
318         } else if (sym.name.length() == 0) {
319             String s;
320             ClassType norm = (ClassType) t.tsym.type;
321             if (norm == null) {
322                 s = localize(locale, "compiler.misc.anonymous.class", (Object) null);
323             } else if (norm.interfaces_field != null && norm.interfaces_field.nonEmpty()) {
324                 s = localize(locale, "compiler.misc.anonymous.class",
325                         visit(norm.interfaces_field.head, locale));
326             } else {
327                 s = localize(locale, "compiler.misc.anonymous.class",
328                         visit(norm.supertype_field, locale));
329             }
330             return s;
331         }
332         String s;
333         if (longform) {
334              s =  sym.getQualifiedName().toString();
335         } else {
336             s =  sym.name.toString();
337         }
338 
339         return s;
340     }
341 
342     /**
343      * Converts a set of method argument types into their corresponding
344      * localized string representation.
345      *
346      * @param args arguments to be rendered
347      * @param varArgs if true, the last method argument is regarded as a vararg
348      * @param locale the locale in which the string is to be rendered
349      * @return localized string representation
350      */
351     protected String printMethodArgs(List<Type> args, boolean varArgs, Locale locale) {
352         if (!varArgs) {
353             return visitTypes(args, locale);
354         } else {
355             StringBuilder buf = new StringBuilder();
356             while (args.tail.nonEmpty()) {
357                 buf.append(visit(args.head, locale));
358                 args = args.tail;
359                 buf.append(',');
360             }
361             if (args.head.hasTag(TypeTag.ARRAY)) {
362                 buf.append(visit(((ArrayType) args.head).elemtype, locale));
363                 if (args.head.getAnnotationMirrors().nonEmpty()) {
364                     buf.append(' ');
365                     buf.append(args.head.getAnnotationMirrors());
366                     buf.append(' ');
367                 }
368                 buf.append("...");
369             } else {
370                 buf.append(visit(args.head, locale));
371             }
372             return buf.toString();
373         }
374     }
375 
376     @Override
377     public String visitClassSymbol(ClassSymbol sym, Locale locale) {
378         return sym.name.isEmpty()
379                 ? localize(locale, "compiler.misc.anonymous.class", sym.flatname)
380                 : sym.fullname.toString();
381     }
382 
383     @Override
384     public String visitMethodSymbol(MethodSymbol s, Locale locale) {
385         if (s.isStaticOrInstanceInit()) {
386             return s.owner.name.toString();
387         } else {
388             String ms = (s.name == s.name.table.names.init)
389                     ? s.owner.name.toString()
390                     : s.name.toString();
391             if (s.type != null) {
392                 if (s.type.hasTag(FORALL)) {
393                     ms = "<" + visitTypes(s.type.getTypeArguments(), locale) + ">" + ms;
394                 }
395                 ms += "(" + printMethodArgs(
396                         s.type.getParameterTypes(),
397                         (s.flags() & VARARGS) != 0,
398                         locale) + ")";
399             }
400             return ms;
401         }
402     }
403 
404     @Override
405     public String visitOperatorSymbol(OperatorSymbol s, Locale locale) {
406         return visitMethodSymbol(s, locale);
407     }
408 
409     @Override
410     public String visitPackageSymbol(PackageSymbol s, Locale locale) {
411         return s.isUnnamed()
412                 ? localize(locale, "compiler.misc.unnamed.package")
413                 : s.fullname.toString();
414     }
415 
416     @Override
417     public String visitTypeSymbol(TypeSymbol s, Locale locale) {
418         return visitSymbol(s, locale);
419     }
420 
421     @Override
422     public String visitVarSymbol(VarSymbol s, Locale locale) {
423         return visitSymbol(s, locale);
424     }
425 
426     @Override
427     public String visitSymbol(Symbol s, Locale locale) {
428         return s.name.toString();
429     }
430 }