Wed, 09 Apr 2008 13:41:45 +0100
5009937: hiding versus generics versus binary compatibility
Summary: missing implementation of JLS 8.4.8.3 (different arguments with same erasure not always triggering a compiler error)
Reviewed-by: jjg
1 /*
2 * Copyright 2005-2006 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 */
26 package com.sun.tools.javac.processing;
28 import javax.annotation.processing.*;
29 import javax.lang.model.*;
30 import javax.lang.model.element.*;
31 import static javax.lang.model.element.ElementKind.*;
32 import static javax.lang.model.element.NestingKind.*;
33 import javax.lang.model.type.*;
34 import javax.lang.model.util.*;
35 import static javax.lang.model.util.ElementFilter.*;
37 import java.io.PrintWriter;
38 import java.io.Writer;
39 import java.util.*;
41 /**
42 * A processor which prints out elements. Used to implement the
43 * -Xprint option; the included visitor class is used to implement
44 * Elements.printElements.
45 *
46 * <p><b>This is NOT part of any API supported by Sun Microsystems.
47 * If you write code that depends on this, you do so at your own risk.
48 * This code and its internal interfaces are subject to change or
49 * deletion without notice.</b>
50 */
51 @SupportedAnnotationTypes("*")
52 @SupportedSourceVersion(SourceVersion.RELEASE_6)
53 public class PrintingProcessor extends AbstractProcessor {
54 PrintWriter writer;
56 public PrintingProcessor() {
57 super();
58 writer = new PrintWriter(System.out);
59 }
61 public void setWriter(Writer w) {
62 writer = new PrintWriter(w);
63 }
65 @Override
66 public boolean process(Set<? extends TypeElement> tes,
67 RoundEnvironment renv) {
69 for(Element element : renv.getRootElements()) {
70 print(element);
71 }
73 // Just print the elements, nothing more to do.
74 return true;
75 }
77 void print(Element element) {
78 new PrintingElementVisitor(writer, processingEnv.getElementUtils()).
79 visit(element).flush();
80 }
82 /**
83 * Used for the -Xprint option and called by Elements.printElements
84 */
85 public static class PrintingElementVisitor
86 extends SimpleElementVisitor6<PrintingElementVisitor, Boolean> {
87 int indentation; // Indentation level;
88 final PrintWriter writer;
89 final Elements elementUtils;
91 public PrintingElementVisitor(Writer w, Elements elementUtils) {
92 super();
93 this.writer = new PrintWriter(w);
94 this.elementUtils = elementUtils;
95 indentation = 0;
96 }
98 @Override
99 protected PrintingElementVisitor defaultAction(Element e, Boolean newLine) {
100 if (newLine != null && newLine)
101 writer.println();
102 printDocComment(e);
103 printModifiers(e);
104 return this;
105 }
107 @Override
108 public PrintingElementVisitor visitExecutable(ExecutableElement e, Boolean p) {
109 ElementKind kind = e.getKind();
111 if (kind != STATIC_INIT &&
112 kind != INSTANCE_INIT) {
113 Element enclosing = e.getEnclosingElement();
115 // Don't print out the constructor of an anonymous class
116 if (kind == CONSTRUCTOR &&
117 enclosing != null &&
118 NestingKind.ANONYMOUS ==
119 // Use an anonymous class to determine anonymity!
120 (new SimpleElementVisitor6<NestingKind, Void>() {
121 @Override
122 public NestingKind visitType(TypeElement e, Void p) {
123 return e.getNestingKind();
124 }
125 }).visit(enclosing))
126 return this;
128 defaultAction(e, true);
129 printFormalTypeParameters(e);
131 switch(kind) {
132 case CONSTRUCTOR:
133 // Print out simple name of the class
134 writer.print(e.getEnclosingElement().getSimpleName());
135 break;
137 case METHOD:
138 writer.print(e.getReturnType().toString());
139 writer.print(" ");
140 writer.print(e.getSimpleName().toString());
141 break;
142 }
144 writer.print("(");
145 printParameters(e);
146 writer.print(")");
147 AnnotationValue defaultValue = e.getDefaultValue();
148 if (defaultValue != null)
149 writer.print(" default " + defaultValue);
151 printThrows(e);
152 writer.println(";");
153 }
154 return this;
155 }
158 @Override
159 public PrintingElementVisitor visitType(TypeElement e, Boolean p) {
160 ElementKind kind = e.getKind();
161 NestingKind nestingKind = e.getNestingKind();
163 if (NestingKind.ANONYMOUS == nestingKind) {
164 // Print out an anonymous class in the style of a
165 // class instance creation expression rather than a
166 // class declaration.
167 writer.print("new ");
169 // If the anonymous class implements an interface
170 // print that name, otherwise print the superclass.
171 List<? extends TypeMirror> interfaces = e.getInterfaces();
172 if (!interfaces.isEmpty())
173 writer.print(interfaces.get(0));
174 else
175 writer.print(e.getSuperclass());
177 writer.print("(");
178 // Anonymous classes that implement an interface can't
179 // have any constructor arguments.
180 if (interfaces.isEmpty()) {
181 // Print out the parameter list from the sole
182 // constructor. For now, don't try to elide any
183 // synthetic parameters by determining if the
184 // anonymous class is in a static context, etc.
185 List<? extends ExecutableElement> constructors =
186 ElementFilter.constructorsIn(e.getEnclosedElements());
188 if (!constructors.isEmpty())
189 printParameters(constructors.get(0));
190 }
191 writer.print(")");
192 } else {
193 if (nestingKind == TOP_LEVEL) {
194 PackageElement pkg = elementUtils.getPackageOf(e);
195 if (!pkg.isUnnamed())
196 writer.print("package " + pkg.getQualifiedName() + ";\n");
197 }
199 defaultAction(e, true);
201 switch(kind) {
202 case ANNOTATION_TYPE:
203 writer.print("@interface");
204 break;
205 default:
206 writer.print(kind.toString().toLowerCase());
207 }
208 writer.print(" ");
209 writer.print(e.getSimpleName());
211 printFormalTypeParameters(e);
213 // Print superclass information if informative
214 if (kind == CLASS) {
215 TypeMirror supertype = e.getSuperclass();
216 if (supertype.getKind() != TypeKind.NONE) {
217 TypeElement e2 = (TypeElement)
218 ((DeclaredType) supertype).asElement();
219 if (e2.getSuperclass().getKind() != TypeKind.NONE)
220 writer.print(" extends " + supertype);
221 }
222 }
224 printInterfaces(e);
225 }
226 writer.println(" {");
227 indentation++;
229 if (kind == ENUM) {
230 List<Element> enclosedElements =
231 new ArrayList<Element>(e.getEnclosedElements());
232 List<Element> enumConstants = new ArrayList<Element>();
233 for(Element element : enclosedElements) {
234 if (element.getKind() == ENUM_CONSTANT)
235 enumConstants.add(element);
236 }
238 int i;
239 for(i = 0; i < enumConstants.size()-1; i++) {
240 this.visit(enumConstants.get(i), true);
241 writer.print(",");
242 }
243 if (i >= 0 ) {
244 this.visit(enumConstants.get(i), true);
245 writer.print(";");
246 }
248 enclosedElements.removeAll(enumConstants);
249 for(Element element : enclosedElements)
250 this.visit(element);
251 } else {
252 for(Element element : e.getEnclosedElements())
253 this.visit(element);
254 }
256 indentation--;
257 indent();
258 writer.println("}");
259 return this;
260 }
262 @Override
263 public PrintingElementVisitor visitVariable(VariableElement e, Boolean newLine) {
264 ElementKind kind = e.getKind();
265 defaultAction(e, newLine);
267 if (kind == ENUM_CONSTANT)
268 writer.print(e.getSimpleName());
269 else {
270 writer.print(e.asType().toString() + " " + e.getSimpleName() );
271 Object constantValue = e.getConstantValue();
272 if (constantValue != null) {
273 writer.print(" = ");
274 writer.print(elementUtils.getConstantExpression(constantValue));
275 }
276 writer.println(";");
277 }
278 return this;
279 }
281 @Override
282 public PrintingElementVisitor visitTypeParameter(TypeParameterElement e, Boolean p) {
283 writer.print(e.getSimpleName());
284 return this;
285 }
287 // Should we do more here?
288 @Override
289 public PrintingElementVisitor visitPackage(PackageElement e, Boolean p) {
290 defaultAction(e, false);
291 if (!e.isUnnamed())
292 writer.println("package " + e.getQualifiedName() + ";");
293 else
294 writer.println("// Unnamed package");
295 return this;
296 }
298 public void flush() {
299 writer.flush();
300 }
302 private void printDocComment(Element e) {
303 String docComment = elementUtils.getDocComment(e);
305 if (docComment != null) {
306 // Break comment into lines
307 java.util.StringTokenizer st = new StringTokenizer(docComment,
308 "\n\r");
309 indent();
310 writer.println("/**");
312 while(st.hasMoreTokens()) {
313 indent();
314 writer.print(" *");
315 writer.println(st.nextToken());
316 }
318 indent();
319 writer.println(" */");
320 }
321 }
323 private void printModifiers(Element e) {
324 ElementKind kind = e.getKind();
325 if (kind == PARAMETER) {
326 printAnnotationsInline(e);
327 } else {
328 printAnnotations(e);
329 indent();
330 }
332 if (kind == ENUM_CONSTANT)
333 return;
335 Set<Modifier> modifiers = new LinkedHashSet<Modifier>();
336 modifiers.addAll(e.getModifiers());
338 switch (kind) {
339 case ANNOTATION_TYPE:
340 case INTERFACE:
341 modifiers.remove(Modifier.ABSTRACT);
342 break;
344 case ENUM:
345 modifiers.remove(Modifier.FINAL);
346 modifiers.remove(Modifier.ABSTRACT);
347 break;
349 case METHOD:
350 case FIELD:
351 Element enclosingElement = e.getEnclosingElement();
352 if (enclosingElement != null &&
353 enclosingElement.getKind().isInterface()) {
354 modifiers.remove(Modifier.PUBLIC);
355 modifiers.remove(Modifier.ABSTRACT); // only for methods
356 modifiers.remove(Modifier.STATIC); // only for fields
357 modifiers.remove(Modifier.FINAL); // only for fields
358 }
359 break;
361 }
363 for(Modifier m: modifiers) {
364 writer.print(m.toString() + " ");
365 }
366 }
368 private void printFormalTypeParameters(ExecutableElement executable) {
369 printFormalTypeParameters(executable.getTypeParameters(), true);
370 }
372 private void printFormalTypeParameters(TypeElement type) {
373 printFormalTypeParameters(type.getTypeParameters(), false);
374 }
376 private void printFormalTypeParameters(List<? extends TypeParameterElement> typeParams,
377 boolean pad) {
378 if (typeParams.size() > 0) {
379 writer.print("<");
381 boolean first = true;
382 for(TypeParameterElement tpe: typeParams) {
383 if (!first)
384 writer.print(", ");
385 writer.print(tpe.toString());
386 first = false;
387 }
389 writer.print(">");
390 if (pad)
391 writer.print(" ");
392 }
393 }
395 private void printAnnotationsInline(Element e) {
396 List<? extends AnnotationMirror> annots = e.getAnnotationMirrors();
397 for(AnnotationMirror annotationMirror : annots) {
398 writer.print(annotationMirror);
399 writer.print(" ");
400 }
401 }
403 private void printAnnotations(Element e) {
404 List<? extends AnnotationMirror> annots = e.getAnnotationMirrors();
405 for(AnnotationMirror annotationMirror : annots) {
406 indent();
407 writer.println(annotationMirror);
408 }
409 }
411 // TODO: Refactor
412 private void printParameters(ExecutableElement e) {
413 List<? extends VariableElement> parameters = e.getParameters();
414 int size = parameters.size();
416 switch (size) {
417 case 0:
418 break;
420 case 1:
421 for(VariableElement parameter: parameters) {
422 printModifiers(parameter);
424 if (e.isVarArgs() ) {
425 TypeMirror tm = parameter.asType();
426 if (tm.getKind() != TypeKind.ARRAY)
427 throw new AssertionError("Var-args parameter is not an array type: " + tm);
428 writer.print((ArrayType.class.cast(tm)).getComponentType() );
429 writer.print("...");
430 } else
431 writer.print(parameter.asType());
432 writer.print(" " + parameter.getSimpleName());
433 }
434 break;
436 default:
437 {
438 int i = 1;
439 for(VariableElement parameter: parameters) {
440 if (i == 2)
441 indentation++;
443 if (i > 1)
444 indent();
446 printModifiers(parameter);
448 if (i == size && e.isVarArgs() ) {
449 TypeMirror tm = parameter.asType();
450 if (tm.getKind() != TypeKind.ARRAY)
451 throw new AssertionError("Var-args parameter is not an array type: " + tm);
452 writer.print((ArrayType.class.cast(tm)).getComponentType() );
454 writer.print("...");
455 } else
456 writer.print(parameter.asType());
457 writer.print(" " + parameter.getSimpleName());
459 if (i < size)
460 writer.println(",");
462 i++;
463 }
465 if (parameters.size() >= 2)
466 indentation--;
467 }
468 break;
469 }
470 }
472 private void printInterfaces(TypeElement e) {
473 ElementKind kind = e.getKind();
475 if(kind != ANNOTATION_TYPE) {
476 List<? extends TypeMirror> interfaces = e.getInterfaces();
477 if (interfaces.size() > 0) {
478 writer.print((kind.isClass() ? " implements" : " extends"));
480 boolean first = true;
481 for(TypeMirror interf: interfaces) {
482 if (!first)
483 writer.print(",");
484 writer.print(" ");
485 writer.print(interf.toString());
486 first = false;
487 }
488 }
489 }
490 }
492 private void printThrows(ExecutableElement e) {
493 List<? extends TypeMirror> thrownTypes = e.getThrownTypes();
494 final int size = thrownTypes.size();
495 if (size != 0) {
496 writer.print(" throws");
498 int i = 1;
499 for(TypeMirror thrownType: thrownTypes) {
500 if (i == 1)
501 writer.print(" ");
503 if (i == 2)
504 indentation++;
506 if (i >= 2)
507 indent();
509 writer.print(thrownType);
511 if (i != size)
512 writer.println(", ");
514 i++;
515 }
517 if (size >= 2)
518 indentation--;
519 }
520 }
522 private static final String [] spaces = {
523 "",
524 " ",
525 " ",
526 " ",
527 " ",
528 " ",
529 " ",
530 " ",
531 " ",
532 " ",
533 " "
534 };
536 private void indent() {
537 int indentation = this.indentation;
538 if (indentation < 0)
539 return;
540 final int maxIndex = spaces.length - 1;
542 while (indentation > maxIndex) {
543 writer.print(spaces[maxIndex]);
544 indentation -= maxIndex;
545 }
546 writer.print(spaces[indentation]);
547 }
549 }
550 }