1 /*
2 * Copyright (c) 1999, 2011, 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.EnumSet;
29 import java.util.Collections;
30 import java.util.Map;
31 import java.util.Set;
32 import javax.lang.model.element.Modifier;
33
34 /** Access flags and other modifiers for Java classes and members.
35 *
36 * <p><b>This is NOT part of any supported API.
37 * If you write code that depends on this, you do so at your own risk.
38 * This code and its internal interfaces are subject to change or
39 * deletion without notice.</b>
40 */
41 public class Flags {
42
43 private Flags() {} // uninstantiable
44
45 public static String toString(long flags) {
46 StringBuilder buf = new StringBuilder();
47 String sep = "";
48 for (Flag s : asFlagSet(flags)) {
49 buf.append(sep);
50 buf.append(s);
51 sep = " ";
52 }
53 return buf.toString();
54 }
55
56 public static EnumSet<Flag> asFlagSet(long mask) {
57 EnumSet<Flag> flags = EnumSet.noneOf(Flag.class);
58 if ((mask&PUBLIC) != 0) flags.add(Flag.PUBLIC);
59 if ((mask&PRIVATE) != 0) flags.add(Flag.PRIVATE);
60 if ((mask&PROTECTED) != 0) flags.add(Flag.PROTECTED);
61 if ((mask&STATIC) != 0) flags.add(Flag.STATIC);
62 if ((mask&FINAL) != 0) flags.add(Flag.FINAL);
63 if ((mask&SYNCHRONIZED) != 0) flags.add(Flag.SYNCHRONIZED);
64 if ((mask&VOLATILE) != 0) flags.add(Flag.VOLATILE);
65 if ((mask&TRANSIENT) != 0) flags.add(Flag.TRANSIENT);
66 if ((mask&NATIVE) != 0) flags.add(Flag.NATIVE);
67 if ((mask&INTERFACE) != 0) flags.add(Flag.INTERFACE);
68 if ((mask&ABSTRACT) != 0) flags.add(Flag.ABSTRACT);
69 if ((mask&STRICTFP) != 0) flags.add(Flag.STRICTFP);
70 if ((mask&BRIDGE) != 0) flags.add(Flag.BRIDGE);
71 if ((mask&SYNTHETIC) != 0) flags.add(Flag.SYNTHETIC);
72 if ((mask&DEPRECATED) != 0) flags.add(Flag.DEPRECATED);
73 if ((mask&HASINIT) != 0) flags.add(Flag.HASINIT);
74 if ((mask&ENUM) != 0) flags.add(Flag.ENUM);
75 if ((mask&IPROXY) != 0) flags.add(Flag.IPROXY);
76 if ((mask&NOOUTERTHIS) != 0) flags.add(Flag.NOOUTERTHIS);
77 if ((mask&EXISTS) != 0) flags.add(Flag.EXISTS);
78 if ((mask&COMPOUND) != 0) flags.add(Flag.COMPOUND);
79 if ((mask&CLASS_SEEN) != 0) flags.add(Flag.CLASS_SEEN);
80 if ((mask&SOURCE_SEEN) != 0) flags.add(Flag.SOURCE_SEEN);
81 if ((mask&LOCKED) != 0) flags.add(Flag.LOCKED);
82 if ((mask&UNATTRIBUTED) != 0) flags.add(Flag.UNATTRIBUTED);
83 if ((mask&ANONCONSTR) != 0) flags.add(Flag.ANONCONSTR);
84 if ((mask&ACYCLIC) != 0) flags.add(Flag.ACYCLIC);
85 if ((mask&PARAMETER) != 0) flags.add(Flag.PARAMETER);
86 if ((mask&VARARGS) != 0) flags.add(Flag.VARARGS);
87 return flags;
88 }
89
90 /* Standard Java flags.
91 */
92 public static final int PUBLIC = 1<<0;
93 public static final int PRIVATE = 1<<1;
94 public static final int PROTECTED = 1<<2;
95 public static final int STATIC = 1<<3;
96 public static final int FINAL = 1<<4;
97 public static final int SYNCHRONIZED = 1<<5;
98 public static final int VOLATILE = 1<<6;
99 public static final int TRANSIENT = 1<<7;
100 public static final int NATIVE = 1<<8;
101 public static final int INTERFACE = 1<<9;
102 public static final int ABSTRACT = 1<<10;
103 public static final int STRICTFP = 1<<11;
104
105 /* Flag that marks a symbol synthetic, added in classfile v49.0. */
106 public static final int SYNTHETIC = 1<<12;
107
108 /** Flag that marks attribute interfaces, added in classfile v49.0. */
109 public static final int ANNOTATION = 1<<13;
110
111 /** An enumeration type or an enumeration constant, added in
112 * classfile v49.0. */
113 public static final int ENUM = 1<<14;
114
115 public static final int StandardFlags = 0x0fff;
116 public static final int ModifierFlags = StandardFlags & ~INTERFACE;
117
118 // Because the following access flags are overloaded with other
119 // bit positions, we translate them when reading and writing class
120 // files into unique bits positions: ACC_SYNTHETIC <-> SYNTHETIC,
121 // for example.
122 public static final int ACC_SUPER = 0x0020;
123 public static final int ACC_BRIDGE = 0x0040;
124 public static final int ACC_VARARGS = 0x0080;
125
126 /*****************************************
127 * Internal compiler flags (no bits in the lower 16).
128 *****************************************/
129
130 /** Flag is set if symbol is deprecated.
131 */
132 public static final int DEPRECATED = 1<<17;
133
134 /** Flag is set for a variable symbol if the variable's definition
135 * has an initializer part.
136 */
137 public static final int HASINIT = 1<<18;
138
139 /** Flag is set for compiler-generated anonymous method symbols
140 * that `own' an initializer block.
141 */
142 public static final int BLOCK = 1<<20;
143
144 /** Flag is set for compiler-generated abstract methods that implement
145 * an interface method (Miranda methods).
146 */
147 public static final int IPROXY = 1<<21;
148
149 /** Flag is set for nested classes that do not access instance members
150 * or `this' of an outer class and therefore don't need to be passed
151 * a this$n reference. This flag is currently set only for anonymous
152 * classes in superclass constructor calls and only for pre 1.4 targets.
153 * todo: use this flag for optimizing away this$n parameters in
154 * other cases.
155 */
156 public static final int NOOUTERTHIS = 1<<22;
157
158 /** Flag is set for package symbols if a package has a member or
159 * directory and therefore exists.
160 */
161 public static final int EXISTS = 1<<23;
162
163 /** Flag is set for compiler-generated compound classes
164 * representing multiple variable bounds
165 */
166 public static final int COMPOUND = 1<<24;
167
168 /** Flag is set for class symbols if a class file was found for this class.
169 */
170 public static final int CLASS_SEEN = 1<<25;
171
172 /** Flag is set for class symbols if a source file was found for this
173 * class.
174 */
175 public static final int SOURCE_SEEN = 1<<26;
176
177 /* State flags (are reset during compilation).
178 */
179
180 /** Flag for class symbols is set and later re-set as a lock in
181 * Enter to detect cycles in the superclass/superinterface
182 * relations. Similarly for constructor call cycle detection in
183 * Attr.
184 */
185 public static final int LOCKED = 1<<27;
186
187 /** Flag for class symbols is set and later re-set to indicate that a class
188 * has been entered but has not yet been attributed.
189 */
190 public static final int UNATTRIBUTED = 1<<28;
191
192 /** Flag for synthesized default constructors of anonymous classes.
193 */
194 public static final int ANONCONSTR = 1<<29;
195
196 /** Flag for class symbols to indicate it has been checked and found
197 * acyclic.
198 */
199 public static final int ACYCLIC = 1<<30;
200
201 /** Flag that marks bridge methods.
202 */
203 public static final long BRIDGE = 1L<<31;
204
205 /** Flag that marks formal parameters.
206 */
207 public static final long PARAMETER = 1L<<33;
208
209 /** Flag that marks varargs methods.
210 */
211 public static final long VARARGS = 1L<<34;
212
213 /** Flag for annotation type symbols to indicate it has been
214 * checked and found acyclic.
215 */
216 public static final long ACYCLIC_ANN = 1L<<35;
217
218 /** Flag that marks a generated default constructor.
219 */
220 public static final long GENERATEDCONSTR = 1L<<36;
221
222 /** Flag that marks a hypothetical method that need not really be
223 * generated in the binary, but is present in the symbol table to
224 * simplify checking for erasure clashes.
225 */
226 public static final long HYPOTHETICAL = 1L<<37;
227
228 /**
229 * Flag that marks an internal proprietary class.
230 */
231 public static final long PROPRIETARY = 1L<<38;
232
233 /**
234 * Flag that marks a a multi-catch parameter
235 */
236 public static final long UNION = 1L<<39;
237
238 /**
239 * Flag that marks a signature-polymorphic invoke method.
240 * (These occur inside java.lang.invoke.MethodHandle.)
241 */
242 public static final long POLYMORPHIC_SIGNATURE = 1L<<40;
243
244 /**
245 * Flag that marks a special kind of bridge methods (the ones that
246 * come from restricted supertype bounds)
247 */
248 public static final long OVERRIDE_BRIDGE = 1L<<41;
249
250 /**
251 * Flag that marks an 'effectively final' local variable
252 */
253 public static final long EFFECTIVELY_FINAL = 1L<<42;
254
255 /**
256 * Flag that marks non-override equivalent methods with the same signature
257 */
258 public static final long CLASH = 1L<<43;
259
260 /** Modifier masks.
261 */
262 public static final int
263 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
264 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC,
265 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
266 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
267 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
268 VarFlags = AccessFlags | FINAL | STATIC |
269 VOLATILE | TRANSIENT | ENUM,
270 ConstructorFlags = AccessFlags,
271 InterfaceMethodFlags = ABSTRACT | PUBLIC,
272 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
273 SYNCHRONIZED | FINAL | STRICTFP;
274 public static final long
275 LocalVarFlags = FINAL | PARAMETER;
276
277 public static Set<Modifier> asModifierSet(long flags) {
278 Set<Modifier> modifiers = modifierSets.get(flags);
279 if (modifiers == null) {
280 modifiers = java.util.EnumSet.noneOf(Modifier.class);
281 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
282 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
283 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
284 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
285 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
286 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
287 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
288 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
289 if (0 != (flags & SYNCHRONIZED))
290 modifiers.add(Modifier.SYNCHRONIZED);
291 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
292 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
293 modifiers = Collections.unmodifiableSet(modifiers);
294 modifierSets.put(flags, modifiers);
295 }
296 return modifiers;
297 }
298
299 // Cache of modifier sets.
300 private static Map<Long, Set<Modifier>> modifierSets =
301 new java.util.concurrent.ConcurrentHashMap<Long, Set<Modifier>>(64);
302
303 public static boolean isStatic(Symbol symbol) {
304 return (symbol.flags() & STATIC) != 0;
305 }
306
307 public static boolean isEnum(Symbol symbol) {
308 return (symbol.flags() & ENUM) != 0;
309 }
310
311 public static boolean isConstant(Symbol.VarSymbol symbol) {
312 return symbol.getConstValue() != null;
313 }
314
315 public enum Flag {
316
317 PUBLIC("public"),
318 PRIVATE("private"),
319 PROTECTED("protected"),
320 STATIC("static"),
321 FINAL("final"),
322 SYNCHRONIZED("synchronized"),
323 VOLATILE("volatile"),
324 TRANSIENT("transient"),
325 NATIVE("native"),
326 INTERFACE("interface"),
327 ABSTRACT("abstract"),
328 STRICTFP("strictfp"),
329 BRIDGE("bridge"),
330 SYNTHETIC("synthetic"),
331 DEPRECATED("deprecated"),
332 HASINIT("hasinit"),
333 ENUM("enum"),
334 IPROXY("iproxy"),
335 NOOUTERTHIS("noouterthis"),
336 EXISTS("exists"),
337 COMPOUND("compound"),
338 CLASS_SEEN("class_seen"),
339 SOURCE_SEEN("source_seen"),
340 LOCKED("locked"),
341 UNATTRIBUTED("unattributed"),
342 ANONCONSTR("anonconstr"),
343 ACYCLIC("acyclic"),
344 PARAMETER("parameter"),
345 VARARGS("varargs"),
346 PACKAGE("package");
347
348 String name;
349
350 Flag(String name) {
351 this.name = name;
352 }
353
354 public String toString() {
355 return name;
356 }
357 }
358 }