Wed, 17 Jul 2013 14:11:41 +0100
8012238: Nested method capture and inference
8008200: java/lang/Class/asSubclass/BasicUnit.java fails to compile
Summary: Inference support should be more flexible w.r.t. nested method calls returning captured types
Reviewed-by: jjg, vromero
1 /*
2 * Copyright (c) 1999, 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 */
26 package com.sun.tools.javac.code;
28 import java.util.Collections;
29 import java.util.EnumSet;
30 import java.util.Map;
31 import java.util.Set;
33 import javax.lang.model.element.Modifier;
35 import com.sun.tools.javac.util.Assert;
37 /** Access flags and other modifiers for Java classes and members.
38 *
39 * <p><b>This is NOT part of any supported API.
40 * If you write code that depends on this, you do so at your own risk.
41 * This code and its internal interfaces are subject to change or
42 * deletion without notice.</b>
43 */
44 public class Flags {
46 private Flags() {} // uninstantiable
48 public static String toString(long flags) {
49 StringBuilder buf = new StringBuilder();
50 String sep = "";
51 for (Flag flag : asFlagSet(flags)) {
52 buf.append(sep);
53 buf.append(flag);
54 sep = " ";
55 }
56 return buf.toString();
57 }
59 public static EnumSet<Flag> asFlagSet(long flags) {
60 EnumSet<Flag> flagSet = EnumSet.noneOf(Flag.class);
61 for (Flag flag : Flag.values()) {
62 if ((flags & flag.value) != 0) {
63 flagSet.add(flag);
64 flags &= ~flag.value;
65 }
66 }
67 Assert.check(flags == 0, "Flags parameter contains unknown flags " + flags);
68 return flagSet;
69 }
71 /* Standard Java flags.
72 */
73 public static final int PUBLIC = 1;
74 public static final int PRIVATE = 1<<1;
75 public static final int PROTECTED = 1<<2;
76 public static final int STATIC = 1<<3;
77 public static final int FINAL = 1<<4;
78 public static final int SYNCHRONIZED = 1<<5;
79 public static final int VOLATILE = 1<<6;
80 public static final int TRANSIENT = 1<<7;
81 public static final int NATIVE = 1<<8;
82 public static final int INTERFACE = 1<<9;
83 public static final int ABSTRACT = 1<<10;
84 public static final int STRICTFP = 1<<11;
86 /* Flag that marks a symbol synthetic, added in classfile v49.0. */
87 public static final int SYNTHETIC = 1<<12;
89 /** Flag that marks attribute interfaces, added in classfile v49.0. */
90 public static final int ANNOTATION = 1<<13;
92 /** An enumeration type or an enumeration constant, added in
93 * classfile v49.0. */
94 public static final int ENUM = 1<<14;
96 /** Added in SE8, represents constructs implicitly declared in source. */
97 public static final int MANDATED = 1<<15;
99 public static final int StandardFlags = 0x0fff;
100 public static final int ModifierFlags = StandardFlags & ~INTERFACE;
102 // Because the following access flags are overloaded with other
103 // bit positions, we translate them when reading and writing class
104 // files into unique bits positions: ACC_SYNTHETIC <-> SYNTHETIC,
105 // for example.
106 public static final int ACC_SUPER = 0x0020;
107 public static final int ACC_BRIDGE = 0x0040;
108 public static final int ACC_VARARGS = 0x0080;
110 /*****************************************
111 * Internal compiler flags (no bits in the lower 16).
112 *****************************************/
114 /** Flag is set if symbol is deprecated.
115 */
116 public static final int DEPRECATED = 1<<17;
118 /** Flag is set for a variable symbol if the variable's definition
119 * has an initializer part.
120 */
121 public static final int HASINIT = 1<<18;
123 /** Flag is set for compiler-generated anonymous method symbols
124 * that `own' an initializer block.
125 */
126 public static final int BLOCK = 1<<20;
128 /** Flag is set for compiler-generated abstract methods that implement
129 * an interface method (Miranda methods).
130 */
131 public static final int IPROXY = 1<<21;
133 /** Flag is set for nested classes that do not access instance members
134 * or `this' of an outer class and therefore don't need to be passed
135 * a this$n reference. This value is currently set only for anonymous
136 * classes in superclass constructor calls and only for pre 1.4 targets.
137 * todo: use this value for optimizing away this$n parameters in
138 * other cases.
139 */
140 public static final int NOOUTERTHIS = 1<<22;
142 /** Flag is set for package symbols if a package has a member or
143 * directory and therefore exists.
144 */
145 public static final int EXISTS = 1<<23;
147 /** Flag is set for compiler-generated compound classes
148 * representing multiple variable bounds
149 */
150 public static final int COMPOUND = 1<<24;
152 /** Flag is set for class symbols if a class file was found for this class.
153 */
154 public static final int CLASS_SEEN = 1<<25;
156 /** Flag is set for class symbols if a source file was found for this
157 * class.
158 */
159 public static final int SOURCE_SEEN = 1<<26;
161 /* State flags (are reset during compilation).
162 */
164 /** Flag for class symbols is set and later re-set as a lock in
165 * Enter to detect cycles in the superclass/superinterface
166 * relations. Similarly for constructor call cycle detection in
167 * Attr.
168 */
169 public static final int LOCKED = 1<<27;
171 /** Flag for class symbols is set and later re-set to indicate that a class
172 * has been entered but has not yet been attributed.
173 */
174 public static final int UNATTRIBUTED = 1<<28;
176 /** Flag for synthesized default constructors of anonymous classes.
177 */
178 public static final int ANONCONSTR = 1<<29;
180 /** Flag for class symbols to indicate it has been checked and found
181 * acyclic.
182 */
183 public static final int ACYCLIC = 1<<30;
185 /** Flag that marks bridge methods.
186 */
187 public static final long BRIDGE = 1L<<31;
189 /** Flag that marks formal parameters.
190 */
191 public static final long PARAMETER = 1L<<33;
193 /** Flag that marks varargs methods.
194 */
195 public static final long VARARGS = 1L<<34;
197 /** Flag for annotation type symbols to indicate it has been
198 * checked and found acyclic.
199 */
200 public static final long ACYCLIC_ANN = 1L<<35;
202 /** Flag that marks a generated default constructor.
203 */
204 public static final long GENERATEDCONSTR = 1L<<36;
206 /** Flag that marks a hypothetical method that need not really be
207 * generated in the binary, but is present in the symbol table to
208 * simplify checking for erasure clashes - also used for 292 poly sig methods.
209 */
210 public static final long HYPOTHETICAL = 1L<<37;
212 /**
213 * Flag that marks an internal proprietary class.
214 */
215 public static final long PROPRIETARY = 1L<<38;
217 /**
218 * Flag that marks a multi-catch parameter.
219 */
220 public static final long UNION = 1L<<39;
222 /**
223 * Flag that marks a special kind of bridge method (the ones that
224 * come from restricted supertype bounds).
225 */
226 public static final long OVERRIDE_BRIDGE = 1L<<40;
228 /**
229 * Flag that marks an 'effectively final' local variable.
230 */
231 public static final long EFFECTIVELY_FINAL = 1L<<41;
233 /**
234 * Flag that marks non-override equivalent methods with the same signature.
235 */
236 public static final long CLASH = 1L<<42;
238 /**
239 * Flag that marks either a default method or an interface containing default methods.
240 */
241 public static final long DEFAULT = 1L<<43;
243 /**
244 * Flag that marks class as auxiliary, ie a non-public class following
245 * the public class in a source file, that could block implicit compilation.
246 */
247 public static final long AUXILIARY = 1L<<44;
249 /**
250 * Flag that marks that a symbol is not available in the current profile
251 */
252 public static final long NOT_IN_PROFILE = 1L<<45;
254 /**
255 * Flag that indicates that an override error has been detected by Check.
256 */
257 public static final long BAD_OVERRIDE = 1L<<45;
259 /**
260 * Flag that indicates a signature polymorphic method (292).
261 */
262 public static final long SIGNATURE_POLYMORPHIC = 1L<<46;
264 /**
265 * Flag that marks inference variables used in a 'throws' clause
266 */
267 public static final long THROWS = 1L<<47;
269 /** Modifier masks.
270 */
271 public static final int
272 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
273 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC,
274 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
275 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
276 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
277 VarFlags = AccessFlags | FINAL | STATIC |
278 VOLATILE | TRANSIENT | ENUM,
279 ConstructorFlags = AccessFlags,
280 InterfaceMethodFlags = ABSTRACT | PUBLIC,
281 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
282 SYNCHRONIZED | FINAL | STRICTFP;
283 public static final long
284 ExtendedStandardFlags = (long)StandardFlags | DEFAULT,
285 InterfaceMethodMask = ABSTRACT | STATIC | PUBLIC | STRICTFP | DEFAULT,
286 LocalVarFlags = FINAL | PARAMETER;
289 public static Set<Modifier> asModifierSet(long flags) {
290 Set<Modifier> modifiers = modifierSets.get(flags);
291 if (modifiers == null) {
292 modifiers = java.util.EnumSet.noneOf(Modifier.class);
293 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
294 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
295 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
296 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
297 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
298 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
299 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
300 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
301 if (0 != (flags & SYNCHRONIZED))
302 modifiers.add(Modifier.SYNCHRONIZED);
303 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
304 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
305 if (0 != (flags & DEFAULT)) modifiers.add(Modifier.DEFAULT);
306 modifiers = Collections.unmodifiableSet(modifiers);
307 modifierSets.put(flags, modifiers);
308 }
309 return modifiers;
310 }
312 // Cache of modifier sets.
313 private static final Map<Long, Set<Modifier>> modifierSets =
314 new java.util.concurrent.ConcurrentHashMap<Long, Set<Modifier>>(64);
316 public static boolean isStatic(Symbol symbol) {
317 return (symbol.flags() & STATIC) != 0;
318 }
320 public static boolean isEnum(Symbol symbol) {
321 return (symbol.flags() & ENUM) != 0;
322 }
324 public static boolean isConstant(Symbol.VarSymbol symbol) {
325 return symbol.getConstValue() != null;
326 }
329 public enum Flag {
330 PUBLIC(Flags.PUBLIC),
331 PRIVATE(Flags.PRIVATE),
332 PROTECTED(Flags.PROTECTED),
333 STATIC(Flags.STATIC),
334 FINAL(Flags.FINAL),
335 SYNCHRONIZED(Flags.SYNCHRONIZED),
336 VOLATILE(Flags.VOLATILE),
337 TRANSIENT(Flags.TRANSIENT),
338 NATIVE(Flags.NATIVE),
339 INTERFACE(Flags.INTERFACE),
340 ABSTRACT(Flags.ABSTRACT),
341 DEFAULT(Flags.DEFAULT),
342 STRICTFP(Flags.STRICTFP),
343 BRIDGE(Flags.BRIDGE),
344 SYNTHETIC(Flags.SYNTHETIC),
345 ANNOTATION(Flags.ANNOTATION),
346 DEPRECATED(Flags.DEPRECATED),
347 HASINIT(Flags.HASINIT),
348 BLOCK(Flags.BLOCK),
349 ENUM(Flags.ENUM),
350 MANDATED(Flags.MANDATED),
351 IPROXY(Flags.IPROXY),
352 NOOUTERTHIS(Flags.NOOUTERTHIS),
353 EXISTS(Flags.EXISTS),
354 COMPOUND(Flags.COMPOUND),
355 CLASS_SEEN(Flags.CLASS_SEEN),
356 SOURCE_SEEN(Flags.SOURCE_SEEN),
357 LOCKED(Flags.LOCKED),
358 UNATTRIBUTED(Flags.UNATTRIBUTED),
359 ANONCONSTR(Flags.ANONCONSTR),
360 ACYCLIC(Flags.ACYCLIC),
361 PARAMETER(Flags.PARAMETER),
362 VARARGS(Flags.VARARGS),
363 ACYCLIC_ANN(Flags.ACYCLIC_ANN),
364 GENERATEDCONSTR(Flags.GENERATEDCONSTR),
365 HYPOTHETICAL(Flags.HYPOTHETICAL),
366 PROPRIETARY(Flags.PROPRIETARY),
367 UNION(Flags.UNION),
368 OVERRIDE_BRIDGE(Flags.OVERRIDE_BRIDGE),
369 EFFECTIVELY_FINAL(Flags.EFFECTIVELY_FINAL),
370 CLASH(Flags.CLASH),
371 AUXILIARY(Flags.AUXILIARY),
372 NOT_IN_PROFILE(Flags.NOT_IN_PROFILE),
373 BAD_OVERRIDE(Flags.BAD_OVERRIDE),
374 SIGNATURE_POLYMORPHIC(Flags.SIGNATURE_POLYMORPHIC),
375 THROWS(Flags.THROWS);
377 Flag(long flag) {
378 this.value = flag;
379 this.lowercaseName = name().toLowerCase();
380 }
382 @Override
383 public String toString() {
384 return lowercaseName;
385 }
387 final long value;
388 final String lowercaseName;
389 }
391 }