1 /*
2 * Copyright (c) 2005, 2016, 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.Arrays;
29 import java.util.EnumSet;
30 import java.util.Map;
31 import java.util.concurrent.ConcurrentHashMap;
32
33 import com.sun.tools.javac.code.Symbol.*;
34 import com.sun.tools.javac.main.Option;
35 import com.sun.tools.javac.util.Context;
36 import com.sun.tools.javac.util.List;
37 import com.sun.tools.javac.util.Options;
38 import com.sun.tools.javac.util.Pair;
39
40 /**
41 * A class for handling -Xlint suboptions and @SuppresssWarnings.
42 *
43 * <p><b>This is NOT part of any supported API.
44 * If you write code that depends on this, you do so at your own risk.
45 * This code and its internal interfaces are subject to change or
46 * deletion without notice.</b>
47 */
48 public class Lint
49 {
50 /** The context key for the root Lint object. */
51 protected static final Context.Key<Lint> lintKey = new Context.Key<>();
52
53 /** Get the root Lint instance. */
54 public static Lint instance(Context context) {
55 Lint instance = context.get(lintKey);
56 if (instance == null)
57 instance = new Lint(context);
58 return instance;
59 }
60
61 /**
62 * Returns the result of combining the values in this object with
63 * the given annotation.
64 */
65 public Lint augment(Attribute.Compound attr) {
66 return augmentor.augment(this, attr);
67 }
68
69
70 /**
71 * Returns the result of combining the values in this object with
72 * the metadata on the given symbol.
73 */
74 public Lint augment(Symbol sym) {
75 Lint l = augmentor.augment(this, sym.getDeclarationAttributes());
76 if (sym.isDeprecated()) {
77 if (l == this)
78 l = new Lint(this);
79 l.values.remove(LintCategory.DEPRECATION);
80 l.suppressedValues.add(LintCategory.DEPRECATION);
81 }
82 return l;
83 }
84
85 /**
86 * Returns a new Lint that has the given LintCategorys suppressed.
87 * @param lc one or more categories to be suppressed
88 */
89 public Lint suppress(LintCategory... lc) {
90 Lint l = new Lint(this);
91 l.values.removeAll(Arrays.asList(lc));
92 l.suppressedValues.addAll(Arrays.asList(lc));
93 return l;
94 }
95
96 private final AugmentVisitor augmentor;
97
98 private final EnumSet<LintCategory> values;
99 private final EnumSet<LintCategory> suppressedValues;
100
101 private static final Map<String, LintCategory> map = new ConcurrentHashMap<>(20);
102
103 protected Lint(Context context) {
104 // initialize values according to the lint options
105 Options options = Options.instance(context);
106
107 if (options.isSet(Option.XLINT) || options.isSet(Option.XLINT_CUSTOM, "all")) {
108 // If -Xlint or -Xlint:all is given, enable all categories by default
109 values = EnumSet.allOf(LintCategory.class);
110 } else if (options.isSet(Option.XLINT_CUSTOM, "none")) {
111 // if -Xlint:none is given, disable all categories by default
112 values = EnumSet.noneOf(LintCategory.class);
113 } else {
114 // otherwise, enable on-by-default categories
115 values = EnumSet.noneOf(LintCategory.class);
116
117 Source source = Source.instance(context);
118 if (source.compareTo(Source.JDK1_9) >= 0) {
119 values.add(LintCategory.DEP_ANN);
120 }
121 values.add(LintCategory.MODULE);
122 values.add(LintCategory.REMOVAL);
123 }
124
125 // Look for specific overrides
126 for (LintCategory lc : LintCategory.values()) {
127 if (options.isSet(Option.XLINT_CUSTOM, lc.option)) {
128 values.add(lc);
129 } else if (options.isSet(Option.XLINT_CUSTOM, "-" + lc.option)) {
130 values.remove(lc);
131 }
132 }
133
134 suppressedValues = EnumSet.noneOf(LintCategory.class);
135
136 context.put(lintKey, this);
137 augmentor = new AugmentVisitor(context);
138 }
139
140 protected Lint(Lint other) {
141 this.augmentor = other.augmentor;
142 this.values = other.values.clone();
143 this.suppressedValues = other.suppressedValues.clone();
144 }
145
146 @Override
147 public String toString() {
148 return "Lint:[values" + values + " suppressedValues" + suppressedValues + "]";
149 }
150
151 /**
152 * Categories of warnings that can be generated by the compiler.
153 */
154 public enum LintCategory {
155 /**
156 * Warn when code refers to a auxiliary class that is hidden in a source file (ie source file name is
157 * different from the class name, and the type is not properly nested) and the referring code
158 * is not located in the same source file.
159 */
160 AUXILIARYCLASS("auxiliaryclass"),
161
162 /**
163 * Warn about use of unnecessary casts.
164 */
165 CAST("cast"),
166
167 /**
168 * Warn about issues related to classfile contents
169 */
170 CLASSFILE("classfile"),
171
172 /**
173 * Warn about use of deprecated items.
174 */
175 DEPRECATION("deprecation"),
176
177 /**
178 * Warn about items which are documented with an {@code @deprecated} JavaDoc
179 * comment, but which do not have {@code @Deprecated} annotation.
180 */
181 DEP_ANN("dep-ann"),
182
183 /**
184 * Warn about division by constant integer 0.
185 */
186 DIVZERO("divzero"),
187
188 /**
189 * Warn about empty statement after if.
190 */
191 EMPTY("empty"),
192
193 /**
194 * Warn about issues regarding module exports.
195 */
196 EXPORTS("exports"),
197
198 /**
199 * Warn about falling through from one case of a switch statement to the next.
200 */
201 FALLTHROUGH("fallthrough"),
202
203 /**
204 * Warn about finally clauses that do not terminate normally.
205 */
206 FINALLY("finally"),
207
208 /**
209 * Warn about module system related issues.
210 */
211 MODULE("module"),
212
213 /**
214 * Warn about issues relating to use of command line options
215 */
216 OPTIONS("options"),
217
218 /**
219 * Warn about issues regarding method overloads.
220 */
221 OVERLOADS("overloads"),
222
223 /**
224 * Warn about issues regarding method overrides.
225 */
226 OVERRIDES("overrides"),
227
228 /**
229 * Warn about invalid path elements on the command line.
230 * Such warnings cannot be suppressed with the SuppressWarnings
231 * annotation.
232 */
233 PATH("path"),
234
235 /**
236 * Warn about issues regarding annotation processing.
237 */
238 PROCESSING("processing"),
239
240 /**
241 * Warn about unchecked operations on raw types.
242 */
243 RAW("rawtypes"),
244
245 /**
246 * Warn about use of deprecated-for-removal items.
247 */
248 REMOVAL("removal"),
249
250 /**
251 * Warn about Serializable classes that do not provide a serial version ID.
252 */
253 SERIAL("serial"),
254
255 /**
256 * Warn about issues relating to use of statics
257 */
258 STATIC("static"),
259
260 /**
261 * Warn about issues relating to use of try blocks (i.e. try-with-resources)
262 */
263 TRY("try"),
264
265 /**
266 * Warn about unchecked operations on raw types.
267 */
268 UNCHECKED("unchecked"),
269
270 /**
271 * Warn about potentially unsafe vararg methods
272 */
273 VARARGS("varargs");
274
275 LintCategory(String option) {
276 this(option, false);
277 }
278
279 LintCategory(String option, boolean hidden) {
280 this.option = option;
281 this.hidden = hidden;
282 map.put(option, this);
283 }
284
285 static LintCategory get(String option) {
286 return map.get(option);
287 }
288
289 public final String option;
290 public final boolean hidden;
291 }
292
293 /**
294 * Checks if a warning category is enabled. A warning category may be enabled
295 * on the command line, or by default, and can be temporarily disabled with
296 * the SuppressWarnings annotation.
297 */
298 public boolean isEnabled(LintCategory lc) {
299 return values.contains(lc);
300 }
301
302 /**
303 * Checks is a warning category has been specifically suppressed, by means
304 * of the SuppressWarnings annotation, or, in the case of the deprecated
305 * category, whether it has been implicitly suppressed by virtue of the
306 * current entity being itself deprecated.
307 */
308 public boolean isSuppressed(LintCategory lc) {
309 return suppressedValues.contains(lc);
310 }
311
312 protected static class AugmentVisitor implements Attribute.Visitor {
313 private final Context context;
314 private Symtab syms;
315 private Lint parent;
316 private Lint lint;
317
318 AugmentVisitor(Context context) {
319 // to break an ugly sequence of initialization dependencies,
320 // we defer the initialization of syms until it is needed
321 this.context = context;
322 }
323
324 Lint augment(Lint parent, Attribute.Compound attr) {
325 initSyms();
326 this.parent = parent;
327 lint = null;
328 attr.accept(this);
329 return (lint == null ? parent : lint);
330 }
331
332 Lint augment(Lint parent, List<Attribute.Compound> attrs) {
333 initSyms();
334 this.parent = parent;
335 lint = null;
336 for (Attribute.Compound a: attrs) {
337 a.accept(this);
338 }
339 return (lint == null ? parent : lint);
340 }
341
342 private void initSyms() {
343 if (syms == null)
344 syms = Symtab.instance(context);
345 }
346
347 private void suppress(LintCategory lc) {
348 if (lint == null)
349 lint = new Lint(parent);
350 lint.suppressedValues.add(lc);
351 lint.values.remove(lc);
352 }
353
354 public void visitConstant(Attribute.Constant value) {
355 if (value.type.tsym == syms.stringType.tsym) {
356 LintCategory lc = LintCategory.get((String) (value.value));
357 if (lc != null)
358 suppress(lc);
359 }
360 }
361
362 public void visitClass(Attribute.Class clazz) {
363 }
364
365 // If we find a @SuppressWarnings annotation, then we continue
366 // walking the tree, in order to suppress the individual warnings
367 // specified in the @SuppressWarnings annotation.
368 public void visitCompound(Attribute.Compound compound) {
369 if (compound.type.tsym == syms.suppressWarningsType.tsym) {
370 for (List<Pair<MethodSymbol,Attribute>> v = compound.values;
371 v.nonEmpty(); v = v.tail) {
372 Pair<MethodSymbol,Attribute> value = v.head;
373 if (value.fst.name.toString().equals("value"))
374 value.snd.accept(this);
375 }
376
377 }
378 }
379
380 public void visitArray(Attribute.Array array) {
381 for (Attribute value : array.values)
382 value.accept(this);
383 }
384
385 public void visitEnum(Attribute.Enum e) {
386 }
387
388 public void visitError(Attribute.Error e) {
389 }
390 }
391 }