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 */
25
26 package com.sun.tools.javac.code;
27
28 import java.util.Collections;
29 import java.util.EnumSet;
30 import java.util.Map;
31 import java.util.Set;
32
33 import javax.lang.model.element.Modifier;
34
35 /** Access flags and other modifiers for Java classes and members.
36 *
37 * <p><b>This is NOT part of any supported API.
38 * If you write code that depends on this, you do so at your own risk.
39 * This code and its internal interfaces are subject to change or
40 * deletion without notice.</b>
41 */
42 public class Flags {
43
44 private Flags() {} // uninstantiable
45
46 public static String toString(long flags) {
47 StringBuilder buf = new StringBuilder();
48 String sep = "";
49 for (Flag s : asFlagSet(flags)) {
50 buf.append(sep);
51 buf.append(s);
52 sep = " ";
53 }
54 return buf.toString();
55 }
56
57 public static EnumSet<Flag> asFlagSet(long mask) {
58 EnumSet<Flag> flags = EnumSet.noneOf(Flag.class);
59 if ((mask&PUBLIC) != 0) flags.add(Flag.PUBLIC);
60 if ((mask&PRIVATE) != 0) flags.add(Flag.PRIVATE);
61 if ((mask&PROTECTED) != 0) flags.add(Flag.PROTECTED);
62 if ((mask&STATIC) != 0) flags.add(Flag.STATIC);
63 if ((mask&FINAL) != 0) flags.add(Flag.FINAL);
64 if ((mask&SYNCHRONIZED) != 0) flags.add(Flag.SYNCHRONIZED);
65 if ((mask&VOLATILE) != 0) flags.add(Flag.VOLATILE);
66 if ((mask&TRANSIENT) != 0) flags.add(Flag.TRANSIENT);
67 if ((mask&NATIVE) != 0) flags.add(Flag.NATIVE);
68 if ((mask&INTERFACE) != 0) flags.add(Flag.INTERFACE);
69 if ((mask&ABSTRACT) != 0) flags.add(Flag.ABSTRACT);
70 if ((mask&DEFAULT) != 0) flags.add(Flag.DEFAULT);
71 if ((mask&STRICTFP) != 0) flags.add(Flag.STRICTFP);
72 if ((mask&BRIDGE) != 0) flags.add(Flag.BRIDGE);
73 if ((mask&SYNTHETIC) != 0) flags.add(Flag.SYNTHETIC);
74 if ((mask&DEPRECATED) != 0) flags.add(Flag.DEPRECATED);
75 if ((mask&HASINIT) != 0) flags.add(Flag.HASINIT);
76 if ((mask&ENUM) != 0) flags.add(Flag.ENUM);
77 if ((mask&IPROXY) != 0) flags.add(Flag.IPROXY);
78 if ((mask&NOOUTERTHIS) != 0) flags.add(Flag.NOOUTERTHIS);
79 if ((mask&EXISTS) != 0) flags.add(Flag.EXISTS);
80 if ((mask&COMPOUND) != 0) flags.add(Flag.COMPOUND);
81 if ((mask&CLASS_SEEN) != 0) flags.add(Flag.CLASS_SEEN);
82 if ((mask&SOURCE_SEEN) != 0) flags.add(Flag.SOURCE_SEEN);
83 if ((mask&LOCKED) != 0) flags.add(Flag.LOCKED);
84 if ((mask&UNATTRIBUTED) != 0) flags.add(Flag.UNATTRIBUTED);
85 if ((mask&ANONCONSTR) != 0) flags.add(Flag.ANONCONSTR);
86 if ((mask&ACYCLIC) != 0) flags.add(Flag.ACYCLIC);
87 if ((mask&PARAMETER) != 0) flags.add(Flag.PARAMETER);
88 if ((mask&VARARGS) != 0) flags.add(Flag.VARARGS);
89 return flags;
90 }
91
92 /* Standard Java flags.
93 */
94 public static final int PUBLIC = 1<<0;
95 public static final int PRIVATE = 1<<1;
96 public static final int PROTECTED = 1<<2;
97 public static final int STATIC = 1<<3;
98 public static final int FINAL = 1<<4;
99 public static final int SYNCHRONIZED = 1<<5;
100 public static final int VOLATILE = 1<<6;
101 public static final int TRANSIENT = 1<<7;
102 public static final int NATIVE = 1<<8;
103 public static final int INTERFACE = 1<<9;
104 public static final int ABSTRACT = 1<<10;
105 public static final int STRICTFP = 1<<11;
106
107 /* Flag that marks a symbol synthetic, added in classfile v49.0. */
108 public static final int SYNTHETIC = 1<<12;
109
110 /** Flag that marks attribute interfaces, added in classfile v49.0. */
111 public static final int ANNOTATION = 1<<13;
112
113 /** An enumeration type or an enumeration constant, added in
114 * classfile v49.0. */
115 public static final int ENUM = 1<<14;
116
117 public static final int StandardFlags = 0x0fff;
118 public static final int ModifierFlags = StandardFlags & ~INTERFACE;
119
120 // Because the following access flags are overloaded with other
121 // bit positions, we translate them when reading and writing class
122 // files into unique bits positions: ACC_SYNTHETIC <-> SYNTHETIC,
123 // for example.
124 public static final int ACC_SUPER = 0x0020;
125 public static final int ACC_BRIDGE = 0x0040;
126 public static final int ACC_VARARGS = 0x0080;
127
128 /*****************************************
129 * Internal compiler flags (no bits in the lower 16).
130 *****************************************/
131
132 /** Flag is set if symbol is deprecated.
133 */
134 public static final int DEPRECATED = 1<<17;
135
136 /** Flag is set for a variable symbol if the variable's definition
137 * has an initializer part.
138 */
139 public static final int HASINIT = 1<<18;
140
141 /** Flag is set for compiler-generated anonymous method symbols
142 * that `own' an initializer block.
143 */
144 public static final int BLOCK = 1<<20;
145
146 /** Flag is set for compiler-generated abstract methods that implement
147 * an interface method (Miranda methods).
148 */
149 public static final int IPROXY = 1<<21;
150
151 /** Flag is set for nested classes that do not access instance members
152 * or `this' of an outer class and therefore don't need to be passed
153 * a this$n reference. This flag is currently set only for anonymous
154 * classes in superclass constructor calls and only for pre 1.4 targets.
155 * todo: use this flag for optimizing away this$n parameters in
156 * other cases.
157 */
158 public static final int NOOUTERTHIS = 1<<22;
159
160 /** Flag is set for package symbols if a package has a member or
161 * directory and therefore exists.
162 */
163 public static final int EXISTS = 1<<23;
164
165 /** Flag is set for compiler-generated compound classes
166 * representing multiple variable bounds
167 */
168 public static final int COMPOUND = 1<<24;
169
170 /** Flag is set for class symbols if a class file was found for this class.
171 */
172 public static final int CLASS_SEEN = 1<<25;
173
174 /** Flag is set for class symbols if a source file was found for this
175 * class.
176 */
177 public static final int SOURCE_SEEN = 1<<26;
178
179 /* State flags (are reset during compilation).
180 */
181
182 /** Flag for class symbols is set and later re-set as a lock in
183 * Enter to detect cycles in the superclass/superinterface
184 * relations. Similarly for constructor call cycle detection in
185 * Attr.
186 */
187 public static final int LOCKED = 1<<27;
188
189 /** Flag for class symbols is set and later re-set to indicate that a class
190 * has been entered but has not yet been attributed.
191 */
192 public static final int UNATTRIBUTED = 1<<28;
193
194 /** Flag for synthesized default constructors of anonymous classes.
195 */
196 public static final int ANONCONSTR = 1<<29;
197
198 /** Flag for class symbols to indicate it has been checked and found
199 * acyclic.
200 */
201 public static final int ACYCLIC = 1<<30;
202
203 /** Flag that marks bridge methods.
204 */
205 public static final long BRIDGE = 1L<<31;
206
207 /** Flag that marks formal parameters.
208 */
209 public static final long PARAMETER = 1L<<33;
210
211 /** Flag that marks varargs methods.
212 */
213 public static final long VARARGS = 1L<<34;
214
215 /** Flag for annotation type symbols to indicate it has been
216 * checked and found acyclic.
217 */
218 public static final long ACYCLIC_ANN = 1L<<35;
219
220 /** Flag that marks a generated default constructor.
221 */
222 public static final long GENERATEDCONSTR = 1L<<36;
223
224 /** Flag that marks a hypothetical method that need not really be
225 * generated in the binary, but is present in the symbol table to
226 * simplify checking for erasure clashes - also used for 292 poly sig methods.
227 */
228 public static final long HYPOTHETICAL = 1L<<37;
229
230 /**
231 * Flag that marks an internal proprietary class.
232 */
233 public static final long PROPRIETARY = 1L<<38;
234
235 /**
236 * Flag that marks a multi-catch parameter.
237 */
238 public static final long UNION = 1L<<39;
239
240 /**
241 * Flag that marks a special kind of bridge method (the ones that
242 * come from restricted supertype bounds).
243 */
244 public static final long OVERRIDE_BRIDGE = 1L<<40;
245
246 /**
247 * Flag that marks an 'effectively final' local variable.
248 */
249 public static final long EFFECTIVELY_FINAL = 1L<<41;
250
251 /**
252 * Flag that marks non-override equivalent methods with the same signature.
253 */
254 public static final long CLASH = 1L<<42;
255
256 /**
257 * Flag that marks either a default method or an interface containing default methods
258 */
259 public static final long DEFAULT = 1L<<43;
260
261 /**
262 * Flag that marks class as auxiliary, ie a non-public class following
263 * the public class in a source file, that could block implicit compilation.
264 */
265 public static final long AUXILIARY = 1L<<44;
266
267 /** Modifier masks.
268 */
269 public static final int
270 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
271 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC,
272 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
273 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
274 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
275 VarFlags = AccessFlags | FINAL | STATIC |
276 VOLATILE | TRANSIENT | ENUM,
277 ConstructorFlags = AccessFlags,
278 InterfaceMethodFlags = ABSTRACT | PUBLIC,
279 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
280 SYNCHRONIZED | FINAL | STRICTFP;
281 public static final long
282 ExtendedStandardFlags = (long)StandardFlags | DEFAULT,
283 InterfaceMethodMask = ABSTRACT | STATIC | PUBLIC | STRICTFP | DEFAULT,
284 LocalVarFlags = FINAL | PARAMETER;
285
286
287 public static Set<Modifier> asModifierSet(long flags) {
288 Set<Modifier> modifiers = modifierSets.get(flags);
289 if (modifiers == null) {
290 modifiers = java.util.EnumSet.noneOf(Modifier.class);
291 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
292 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
293 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
294 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
295 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
296 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
297 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
298 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
299 if (0 != (flags & SYNCHRONIZED))
300 modifiers.add(Modifier.SYNCHRONIZED);
301 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
302 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
303 modifiers = Collections.unmodifiableSet(modifiers);
304 modifierSets.put(flags, modifiers);
305 }
306 return modifiers;
307 }
308
309 // Cache of modifier sets.
310 private static final Map<Long, Set<Modifier>> modifierSets =
311 new java.util.concurrent.ConcurrentHashMap<Long, Set<Modifier>>(64);
312
313 public static boolean isStatic(Symbol symbol) {
314 return (symbol.flags() & STATIC) != 0;
315 }
316
317 public static boolean isEnum(Symbol symbol) {
318 return (symbol.flags() & ENUM) != 0;
319 }
320
321 public static boolean isConstant(Symbol.VarSymbol symbol) {
322 return symbol.getConstValue() != null;
323 }
324
325 public enum Flag {
326
327 PUBLIC("public"),
328 PRIVATE("private"),
329 PROTECTED("protected"),
330 STATIC("static"),
331 FINAL("final"),
332 SYNCHRONIZED("synchronized"),
333 VOLATILE("volatile"),
334 TRANSIENT("transient"),
335 NATIVE("native"),
336 INTERFACE("interface"),
337 ABSTRACT("abstract"),
338 DEFAULT("default"),
339 STRICTFP("strictfp"),
340 BRIDGE("bridge"),
341 SYNTHETIC("synthetic"),
342 DEPRECATED("deprecated"),
343 HASINIT("hasinit"),
344 ENUM("enum"),
345 IPROXY("iproxy"),
346 NOOUTERTHIS("noouterthis"),
347 EXISTS("exists"),
348 COMPOUND("compound"),
349 CLASS_SEEN("class_seen"),
350 SOURCE_SEEN("source_seen"),
351 LOCKED("locked"),
352 UNATTRIBUTED("unattributed"),
353 ANONCONSTR("anonconstr"),
354 ACYCLIC("acyclic"),
355 PARAMETER("parameter"),
356 VARARGS("varargs"),
357 PACKAGE("package");
358
359 private final String name;
360
361 Flag(String name) {
362 this.name = name;
363 }
364
365 public String toString() {
366 return name;
367 }
368 }
369 }