1 /*
2 * Copyright 1999-2008 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any 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 API supported by Sun Microsystems. If
37 * 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 StringBuffer buf = new StringBuffer();
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
117 // Because the following access flags are overloaded with other
118 // bit positions, we translate them when reading and writing class
119 // files into unique bits positions: ACC_SYNTHETIC <-> SYNTHETIC,
120 // for example.
121 public static final int ACC_SUPER = 0x0020;
122 public static final int ACC_BRIDGE = 0x0040;
123 public static final int ACC_VARARGS = 0x0080;
124
125 /*****************************************
126 * Internal compiler flags (no bits in the lower 16).
127 *****************************************/
128
129 /** Flag is set if symbol is deprecated.
130 */
131 public static final int DEPRECATED = 1<<17;
132
133 /** Flag is set for a variable symbol if the variable's definition
134 * has an initializer part.
135 */
136 public static final int HASINIT = 1<<18;
137
138 /** Flag is set for compiler-generated anonymous method symbols
139 * that `own' an initializer block.
140 */
141 public static final int BLOCK = 1<<20;
142
143 /** Flag is set for compiler-generated abstract methods that implement
144 * an interface method (Miranda methods).
145 */
146 public static final int IPROXY = 1<<21;
147
148 /** Flag is set for nested classes that do not access instance members
149 * or `this' of an outer class and therefore don't need to be passed
150 * a this$n reference. This flag is currently set only for anonymous
151 * classes in superclass constructor calls and only for pre 1.4 targets.
152 * todo: use this flag for optimizing away this$n parameters in
153 * other cases.
154 */
155 public static final int NOOUTERTHIS = 1<<22;
156
157 /** Flag is set for package symbols if a package has a member or
158 * directory and therefore exists.
159 */
160 public static final int EXISTS = 1<<23;
161
162 /** Flag is set for compiler-generated compound classes
163 * representing multiple variable bounds
164 */
165 public static final int COMPOUND = 1<<24;
166
167 /** Flag is set for class symbols if a class file was found for this class.
168 */
169 public static final int CLASS_SEEN = 1<<25;
170
171 /** Flag is set for class symbols if a source file was found for this
172 * class.
173 */
174 public static final int SOURCE_SEEN = 1<<26;
175
176 /* State flags (are reset during compilation).
177 */
178
179 /** Flag for class symbols is set and later re-set as a lock in
180 * Enter to detect cycles in the superclass/superinterface
181 * relations. Similarly for constructor call cycle detection in
182 * Attr.
183 */
184 public static final int LOCKED = 1<<27;
185
186 /** Flag for class symbols is set and later re-set to indicate that a class
187 * has been entered but has not yet been attributed.
188 */
189 public static final int UNATTRIBUTED = 1<<28;
190
191 /** Flag for synthesized default constructors of anonymous classes.
192 */
193 public static final int ANONCONSTR = 1<<29;
194
195 /** Flag for class symbols to indicate it has been checked and found
196 * acyclic.
197 */
198 public static final int ACYCLIC = 1<<30;
199
200 /** Flag that marks bridge methods.
201 */
202 public static final long BRIDGE = 1L<<31;
203
204 /** Flag that marks formal parameters.
205 */
206 public static final long PARAMETER = 1L<<33;
207
208 /** Flag that marks varargs methods.
209 */
210 public static final long VARARGS = 1L<<34;
211
212 /** Flag for annotation type symbols to indicate it has been
213 * checked and found acyclic.
214 */
215 public static final long ACYCLIC_ANN = 1L<<35;
216
217 /** Flag that marks a generated default constructor.
218 */
219 public static final long GENERATEDCONSTR = 1L<<36;
220
221 /** Flag that marks a hypothetical method that need not really be
222 * generated in the binary, but is present in the symbol table to
223 * simplify checking for erasure clashes.
224 */
225 public static final long HYPOTHETICAL = 1L<<37;
226
227 /**
228 * Flag that marks a Sun proprietary class.
229 */
230 public static final long PROPRIETARY = 1L<<38;
231
232 /** Modifier masks.
233 */
234 public static final int
235 AccessFlags = PUBLIC | PROTECTED | PRIVATE,
236 LocalClassFlags = FINAL | ABSTRACT | STRICTFP | ENUM | SYNTHETIC,
237 MemberClassFlags = LocalClassFlags | INTERFACE | AccessFlags,
238 ClassFlags = LocalClassFlags | INTERFACE | PUBLIC | ANNOTATION,
239 InterfaceVarFlags = FINAL | STATIC | PUBLIC,
240 VarFlags = AccessFlags | FINAL | STATIC |
241 VOLATILE | TRANSIENT | ENUM,
242 ConstructorFlags = AccessFlags,
243 InterfaceMethodFlags = ABSTRACT | PUBLIC,
244 MethodFlags = AccessFlags | ABSTRACT | STATIC | NATIVE |
245 SYNCHRONIZED | FINAL | STRICTFP;
246 public static final long
247 LocalVarFlags = FINAL | PARAMETER;
248
249 public static Set<Modifier> asModifierSet(long flags) {
250 Set<Modifier> modifiers = modifierSets.get(flags);
251 if (modifiers == null) {
252 modifiers = java.util.EnumSet.noneOf(Modifier.class);
253 if (0 != (flags & PUBLIC)) modifiers.add(Modifier.PUBLIC);
254 if (0 != (flags & PROTECTED)) modifiers.add(Modifier.PROTECTED);
255 if (0 != (flags & PRIVATE)) modifiers.add(Modifier.PRIVATE);
256 if (0 != (flags & ABSTRACT)) modifiers.add(Modifier.ABSTRACT);
257 if (0 != (flags & STATIC)) modifiers.add(Modifier.STATIC);
258 if (0 != (flags & FINAL)) modifiers.add(Modifier.FINAL);
259 if (0 != (flags & TRANSIENT)) modifiers.add(Modifier.TRANSIENT);
260 if (0 != (flags & VOLATILE)) modifiers.add(Modifier.VOLATILE);
261 if (0 != (flags & SYNCHRONIZED))
262 modifiers.add(Modifier.SYNCHRONIZED);
263 if (0 != (flags & NATIVE)) modifiers.add(Modifier.NATIVE);
264 if (0 != (flags & STRICTFP)) modifiers.add(Modifier.STRICTFP);
265 modifiers = Collections.unmodifiableSet(modifiers);
266 modifierSets.put(flags, modifiers);
267 }
268 return modifiers;
269 }
270
271 // Cache of modifier sets.
272 private static Map<Long, Set<Modifier>> modifierSets =
273 new java.util.concurrent.ConcurrentHashMap<Long, Set<Modifier>>(64);
274
275 public static boolean isStatic(Symbol symbol) {
276 return (symbol.flags() & STATIC) != 0;
277 }
278
279 public static boolean isEnum(Symbol symbol) {
280 return (symbol.flags() & ENUM) != 0;
281 }
282
283 public static boolean isConstant(Symbol.VarSymbol symbol) {
284 return symbol.getConstValue() != null;
285 }
286
287 public enum Flag {
288
289 PUBLIC("public"),
290 PRIVATE("private"),
291 PROTECTED("protected"),
292 STATIC("static"),
293 FINAL("final"),
294 SYNCHRONIZED("synchronized"),
295 VOLATILE("volatile"),
296 TRANSIENT("transient"),
297 NATIVE("native"),
298 INTERFACE("interface"),
299 ABSTRACT("abstract"),
300 STRICTFP("strictfp"),
301 BRIDGE("bridge"),
302 SYNTHETIC("synthetic"),
303 DEPRECATED("deprecated"),
304 HASINIT("hasinit"),
305 ENUM("enum"),
306 IPROXY("iproxy"),
307 NOOUTERTHIS("noouterthis"),
308 EXISTS("exists"),
309 COMPOUND("compound"),
310 CLASS_SEEN("class_seen"),
311 SOURCE_SEEN("source_seen"),
312 LOCKED("locked"),
313 UNATTRIBUTED("unattributed"),
314 ANONCONSTR("anonconstr"),
315 ACYCLIC("acyclic"),
316 PARAMETER("parameter"),
317 VARARGS("varargs"),
318 PACKAGE("package");
319
320 String name;
321
322 Flag(String name) {
323 this.name = name;
324 }
325
326 public String toString() {
327 return name;
328 }
329 }
330 }