Mon, 02 Sep 2013 22:38:36 +0100
8016177: structural most specific and stuckness
Reviewed-by: jjg, vromero
Contributed-by: maurizio.cimadamore@oracle.com
1 /*
2 * Copyright (c) 2005, 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.EnumSet;
29 import java.util.Map;
30 import com.sun.tools.javac.code.Symbol.*;
31 import com.sun.tools.javac.util.Context;
32 import com.sun.tools.javac.util.List;
33 import com.sun.tools.javac.util.Options;
34 import com.sun.tools.javac.util.Pair;
36 import static com.sun.tools.javac.code.Flags.*;
39 /**
40 * A class for handling -Xlint suboptions and @SuppresssWarnings.
41 *
42 * <p><b>This is NOT part of any supported API.
43 * If you write code that depends on this, you do so at your own risk.
44 * This code and its internal interfaces are subject to change or
45 * deletion without notice.</b>
46 */
47 public class Lint
48 {
49 /** The context key for the root Lint object. */
50 protected static final Context.Key<Lint> lintKey = new Context.Key<Lint>();
52 /** Get the root Lint instance. */
53 public static Lint instance(Context context) {
54 Lint instance = context.get(lintKey);
55 if (instance == null)
56 instance = new Lint(context);
57 return instance;
58 }
60 /**
61 * Returns the result of combining the values in this object with
62 * the given annotation.
63 */
64 public Lint augment(Attribute.Compound attr) {
65 return augmentor.augment(this, attr);
66 }
69 /**
70 * Returns the result of combining the values in this object with
71 * the metadata on the given symbol.
72 */
73 public Lint augment(Symbol sym) {
74 Lint l = augmentor.augment(this, sym.getDeclarationAttributes());
75 if (sym.isDeprecated()) {
76 if (l == this)
77 l = new Lint(this);
78 l.values.remove(LintCategory.DEPRECATION);
79 l.suppressedValues.add(LintCategory.DEPRECATION);
80 }
81 return l;
82 }
85 private final AugmentVisitor augmentor;
87 private final EnumSet<LintCategory> values;
88 private final EnumSet<LintCategory> suppressedValues;
90 private static final Map<String, LintCategory> map =
91 new java.util.concurrent.ConcurrentHashMap<String, LintCategory>(20);
94 protected Lint(Context context) {
95 // initialize values according to the lint options
96 Options options = Options.instance(context);
97 values = EnumSet.noneOf(LintCategory.class);
98 for (Map.Entry<String, LintCategory> e: map.entrySet()) {
99 if (options.lint(e.getKey()))
100 values.add(e.getValue());
101 }
103 suppressedValues = EnumSet.noneOf(LintCategory.class);
105 context.put(lintKey, this);
106 augmentor = new AugmentVisitor(context);
107 }
109 protected Lint(Lint other) {
110 this.augmentor = other.augmentor;
111 this.values = other.values.clone();
112 this.suppressedValues = other.suppressedValues.clone();
113 }
115 @Override
116 public String toString() {
117 return "Lint:[values" + values + " suppressedValues" + suppressedValues + "]";
118 }
120 /**
121 * Categories of warnings that can be generated by the compiler.
122 */
123 public enum LintCategory {
124 /**
125 * Warn when code refers to a auxiliary class that is hidden in a source file (ie source file name is
126 * different from the class name, and the type is not properly nested) and the referring code
127 * is not located in the same source file.
128 */
129 AUXILIARYCLASS("auxiliaryclass"),
131 /**
132 * Warn about use of unnecessary casts.
133 */
134 CAST("cast"),
136 /**
137 * Warn about issues related to classfile contents
138 */
139 CLASSFILE("classfile"),
141 /**
142 * Warn about use of deprecated items.
143 */
144 DEPRECATION("deprecation"),
146 /**
147 * Warn about items which are documented with an {@code @deprecated} JavaDoc
148 * comment, but which do not have {@code @Deprecated} annotation.
149 */
150 DEP_ANN("dep-ann"),
152 /**
153 * Warn about division by constant integer 0.
154 */
155 DIVZERO("divzero"),
157 /**
158 * Warn about empty statement after if.
159 */
160 EMPTY("empty"),
162 /**
163 * Warn about falling through from one case of a switch statement to the next.
164 */
165 FALLTHROUGH("fallthrough"),
167 /**
168 * Warn about finally clauses that do not terminate normally.
169 */
170 FINALLY("finally"),
172 /**
173 * Warn about issues relating to use of command line options
174 */
175 OPTIONS("options"),
177 /**
178 * Warn about issues regarding method overloads.
179 */
180 OVERLOADS("overloads"),
182 /**
183 * Warn about issues regarding method overrides.
184 */
185 OVERRIDES("overrides"),
187 /**
188 * Warn about invalid path elements on the command line.
189 * Such warnings cannot be suppressed with the SuppressWarnings
190 * annotation.
191 */
192 PATH("path"),
194 /**
195 * Warn about issues regarding annotation processing.
196 */
197 PROCESSING("processing"),
199 /**
200 * Warn about unchecked operations on raw types.
201 */
202 RAW("rawtypes"),
204 /**
205 * Warn about Serializable classes that do not provide a serial version ID.
206 */
207 SERIAL("serial"),
209 /**
210 * Warn about issues relating to use of statics
211 */
212 STATIC("static"),
214 /**
215 * Warn about proprietary API that may be removed in a future release.
216 */
217 SUNAPI("sunapi", true),
219 /**
220 * Warn about issues relating to use of try blocks (i.e. try-with-resources)
221 */
222 TRY("try"),
224 /**
225 * Warn about unchecked operations on raw types.
226 */
227 UNCHECKED("unchecked"),
229 /**
230 * Warn about potentially unsafe vararg methods
231 */
232 VARARGS("varargs");
234 LintCategory(String option) {
235 this(option, false);
236 }
238 LintCategory(String option, boolean hidden) {
239 this.option = option;
240 this.hidden = hidden;
241 map.put(option, this);
242 }
244 static LintCategory get(String option) {
245 return map.get(option);
246 }
248 public final String option;
249 public final boolean hidden;
250 };
252 /**
253 * Checks if a warning category is enabled. A warning category may be enabled
254 * on the command line, or by default, and can be temporarily disabled with
255 * the SuppressWarnings annotation.
256 */
257 public boolean isEnabled(LintCategory lc) {
258 return values.contains(lc);
259 }
261 /**
262 * Checks is a warning category has been specifically suppressed, by means
263 * of the SuppressWarnings annotation, or, in the case of the deprecated
264 * category, whether it has been implicitly suppressed by virtue of the
265 * current entity being itself deprecated.
266 */
267 public boolean isSuppressed(LintCategory lc) {
268 return suppressedValues.contains(lc);
269 }
271 protected static class AugmentVisitor implements Attribute.Visitor {
272 private final Context context;
273 private Symtab syms;
274 private Lint parent;
275 private Lint lint;
277 AugmentVisitor(Context context) {
278 // to break an ugly sequence of initialization dependencies,
279 // we defer the initialization of syms until it is needed
280 this.context = context;
281 }
283 Lint augment(Lint parent, Attribute.Compound attr) {
284 initSyms();
285 this.parent = parent;
286 lint = null;
287 attr.accept(this);
288 return (lint == null ? parent : lint);
289 }
291 Lint augment(Lint parent, List<Attribute.Compound> attrs) {
292 initSyms();
293 this.parent = parent;
294 lint = null;
295 for (Attribute.Compound a: attrs) {
296 a.accept(this);
297 }
298 return (lint == null ? parent : lint);
299 }
301 private void initSyms() {
302 if (syms == null)
303 syms = Symtab.instance(context);
304 }
306 private void suppress(LintCategory lc) {
307 if (lint == null)
308 lint = new Lint(parent);
309 lint.suppressedValues.add(lc);
310 lint.values.remove(lc);
311 }
313 public void visitConstant(Attribute.Constant value) {
314 if (value.type.tsym == syms.stringType.tsym) {
315 LintCategory lc = LintCategory.get((String) (value.value));
316 if (lc != null)
317 suppress(lc);
318 }
319 }
321 public void visitClass(Attribute.Class clazz) {
322 }
324 // If we find a @SuppressWarnings annotation, then we continue
325 // walking the tree, in order to suppress the individual warnings
326 // specified in the @SuppressWarnings annotation.
327 public void visitCompound(Attribute.Compound compound) {
328 if (compound.type.tsym == syms.suppressWarningsType.tsym) {
329 for (List<Pair<MethodSymbol,Attribute>> v = compound.values;
330 v.nonEmpty(); v = v.tail) {
331 Pair<MethodSymbol,Attribute> value = v.head;
332 if (value.fst.name.toString().equals("value"))
333 value.snd.accept(this);
334 }
336 }
337 }
339 public void visitArray(Attribute.Array array) {
340 for (Attribute value : array.values)
341 value.accept(this);
342 }
344 public void visitEnum(Attribute.Enum e) {
345 }
347 public void visitError(Attribute.Error e) {
348 }
349 };
350 }