001 /*
002 * Copyright 1999-2008 Sun Microsystems, Inc. All Rights Reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation. Sun designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Sun in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
018 * 2 along with this work; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022 * CA 95054 USA or visit www.sun.com if you need additional information or
023 * have any questions.
024 */
025
026 package com.sun.tools.javac.tree;
027
028 import com.sun.source.tree.Tree;
029 import com.sun.tools.javac.comp.AttrContext;
030 import com.sun.tools.javac.comp.Env;
031 import java.util.Map;
032 import com.sun.tools.javac.util.*;
033 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
034 import com.sun.tools.javac.code.*;
035 import com.sun.tools.javac.tree.JCTree.*;
036
037 import static com.sun.tools.javac.code.Flags.*;
038
039 /** Utility class containing inspector methods for trees.
040 *
041 * <p><b>This is NOT part of any API supported by Sun Microsystems. If
042 * you write code that depends on this, you do so at your own risk.
043 * This code and its internal interfaces are subject to change or
044 * deletion without notice.</b>
045 */
046 public class TreeInfo {
047 protected static final Context.Key<TreeInfo> treeInfoKey =
048 new Context.Key<TreeInfo>();
049
050 public static TreeInfo instance(Context context) {
051 TreeInfo instance = context.get(treeInfoKey);
052 if (instance == null)
053 instance = new TreeInfo(context);
054 return instance;
055 }
056
057 /** The names of all operators.
058 */
059 private Name[] opname = new Name[JCTree.MOD - JCTree.POS + 1];
060
061 private TreeInfo(Context context) {
062 context.put(treeInfoKey, this);
063
064 Names names = Names.instance(context);
065 opname[JCTree.POS - JCTree.POS] = names.fromString("+");
066 opname[JCTree.NEG - JCTree.POS] = names.hyphen;
067 opname[JCTree.NOT - JCTree.POS] = names.fromString("!");
068 opname[JCTree.COMPL - JCTree.POS] = names.fromString("~");
069 opname[JCTree.PREINC - JCTree.POS] = names.fromString("++");
070 opname[JCTree.PREDEC - JCTree.POS] = names.fromString("--");
071 opname[JCTree.POSTINC - JCTree.POS] = names.fromString("++");
072 opname[JCTree.POSTDEC - JCTree.POS] = names.fromString("--");
073 opname[JCTree.NULLCHK - JCTree.POS] = names.fromString("<*nullchk*>");
074 opname[JCTree.OR - JCTree.POS] = names.fromString("||");
075 opname[JCTree.AND - JCTree.POS] = names.fromString("&&");
076 opname[JCTree.EQ - JCTree.POS] = names.fromString("==");
077 opname[JCTree.NE - JCTree.POS] = names.fromString("!=");
078 opname[JCTree.LT - JCTree.POS] = names.fromString("<");
079 opname[JCTree.GT - JCTree.POS] = names.fromString(">");
080 opname[JCTree.LE - JCTree.POS] = names.fromString("<=");
081 opname[JCTree.GE - JCTree.POS] = names.fromString(">=");
082 opname[JCTree.BITOR - JCTree.POS] = names.fromString("|");
083 opname[JCTree.BITXOR - JCTree.POS] = names.fromString("^");
084 opname[JCTree.BITAND - JCTree.POS] = names.fromString("&");
085 opname[JCTree.SL - JCTree.POS] = names.fromString("<<");
086 opname[JCTree.SR - JCTree.POS] = names.fromString(">>");
087 opname[JCTree.USR - JCTree.POS] = names.fromString(">>>");
088 opname[JCTree.PLUS - JCTree.POS] = names.fromString("+");
089 opname[JCTree.MINUS - JCTree.POS] = names.hyphen;
090 opname[JCTree.MUL - JCTree.POS] = names.asterisk;
091 opname[JCTree.DIV - JCTree.POS] = names.slash;
092 opname[JCTree.MOD - JCTree.POS] = names.fromString("%");
093 }
094
095
096 /** Return name of operator with given tree tag.
097 */
098 public Name operatorName(int tag) {
099 return opname[tag - JCTree.POS];
100 }
101
102 /** Is tree a constructor declaration?
103 */
104 public static boolean isConstructor(JCTree tree) {
105 if (tree.getTag() == JCTree.METHODDEF) {
106 Name name = ((JCMethodDecl) tree).name;
107 return name == name.table.names.init;
108 } else {
109 return false;
110 }
111 }
112
113 /** Is there a constructor declaration in the given list of trees?
114 */
115 public static boolean hasConstructors(List<JCTree> trees) {
116 for (List<JCTree> l = trees; l.nonEmpty(); l = l.tail)
117 if (isConstructor(l.head)) return true;
118 return false;
119 }
120
121 /** Is statement an initializer for a synthetic field?
122 */
123 public static boolean isSyntheticInit(JCTree stat) {
124 if (stat.getTag() == JCTree.EXEC) {
125 JCExpressionStatement exec = (JCExpressionStatement)stat;
126 if (exec.expr.getTag() == JCTree.ASSIGN) {
127 JCAssign assign = (JCAssign)exec.expr;
128 if (assign.lhs.getTag() == JCTree.SELECT) {
129 JCFieldAccess select = (JCFieldAccess)assign.lhs;
130 if (select.sym != null &&
131 (select.sym.flags() & SYNTHETIC) != 0) {
132 Name selected = name(select.selected);
133 if (selected != null && selected == selected.table.names._this)
134 return true;
135 }
136 }
137 }
138 }
139 return false;
140 }
141
142 /** If the expression is a method call, return the method name, null
143 * otherwise. */
144 public static Name calledMethodName(JCTree tree) {
145 if (tree.getTag() == JCTree.EXEC) {
146 JCExpressionStatement exec = (JCExpressionStatement)tree;
147 if (exec.expr.getTag() == JCTree.APPLY) {
148 Name mname = TreeInfo.name(((JCMethodInvocation) exec.expr).meth);
149 return mname;
150 }
151 }
152 return null;
153 }
154
155 /** Is this a call to this or super?
156 */
157 public static boolean isSelfCall(JCTree tree) {
158 Name name = calledMethodName(tree);
159 if (name != null) {
160 Names names = name.table.names;
161 return name==names._this || name==names._super;
162 } else {
163 return false;
164 }
165 }
166
167 /** Is this a call to super?
168 */
169 public static boolean isSuperCall(JCTree tree) {
170 Name name = calledMethodName(tree);
171 if (name != null) {
172 Names names = name.table.names;
173 return name==names._super;
174 } else {
175 return false;
176 }
177 }
178
179 /** Is this a constructor whose first (non-synthetic) statement is not
180 * of the form this(...)?
181 */
182 public static boolean isInitialConstructor(JCTree tree) {
183 JCMethodInvocation app = firstConstructorCall(tree);
184 if (app == null) return false;
185 Name meth = name(app.meth);
186 return meth == null || meth != meth.table.names._this;
187 }
188
189 /** Return the first call in a constructor definition. */
190 public static JCMethodInvocation firstConstructorCall(JCTree tree) {
191 if (tree.getTag() != JCTree.METHODDEF) return null;
192 JCMethodDecl md = (JCMethodDecl) tree;
193 Names names = md.name.table.names;
194 if (md.name != names.init) return null;
195 if (md.body == null) return null;
196 List<JCStatement> stats = md.body.stats;
197 // Synthetic initializations can appear before the super call.
198 while (stats.nonEmpty() && isSyntheticInit(stats.head))
199 stats = stats.tail;
200 if (stats.isEmpty()) return null;
201 if (stats.head.getTag() != JCTree.EXEC) return null;
202 JCExpressionStatement exec = (JCExpressionStatement) stats.head;
203 if (exec.expr.getTag() != JCTree.APPLY) return null;
204 return (JCMethodInvocation)exec.expr;
205 }
206
207 /** Return true if a tree represents the null literal. */
208 public static boolean isNull(JCTree tree) {
209 if (tree.getTag() != JCTree.LITERAL)
210 return false;
211 JCLiteral lit = (JCLiteral) tree;
212 return (lit.typetag == TypeTags.BOT);
213 }
214
215 /** The position of the first statement in a block, or the position of
216 * the block itself if it is empty.
217 */
218 public static int firstStatPos(JCTree tree) {
219 if (tree.getTag() == JCTree.BLOCK && ((JCBlock) tree).stats.nonEmpty())
220 return ((JCBlock) tree).stats.head.pos;
221 else
222 return tree.pos;
223 }
224
225 /** The end position of given tree, if it is a block with
226 * defined endpos.
227 */
228 public static int endPos(JCTree tree) {
229 if (tree.getTag() == JCTree.BLOCK && ((JCBlock) tree).endpos != Position.NOPOS)
230 return ((JCBlock) tree).endpos;
231 else if (tree.getTag() == JCTree.SYNCHRONIZED)
232 return endPos(((JCSynchronized) tree).body);
233 else if (tree.getTag() == JCTree.TRY) {
234 JCTry t = (JCTry) tree;
235 return endPos((t.finalizer != null)
236 ? t.finalizer
237 : t.catchers.last().body);
238 } else
239 return tree.pos;
240 }
241
242
243 /** Get the start position for a tree node. The start position is
244 * defined to be the position of the first character of the first
245 * token of the node's source text.
246 * @param tree The tree node
247 */
248 public static int getStartPos(JCTree tree) {
249 if (tree == null)
250 return Position.NOPOS;
251
252 switch(tree.getTag()) {
253 case(JCTree.APPLY):
254 return getStartPos(((JCMethodInvocation) tree).meth);
255 case(JCTree.ASSIGN):
256 return getStartPos(((JCAssign) tree).lhs);
257 case(JCTree.BITOR_ASG): case(JCTree.BITXOR_ASG): case(JCTree.BITAND_ASG):
258 case(JCTree.SL_ASG): case(JCTree.SR_ASG): case(JCTree.USR_ASG):
259 case(JCTree.PLUS_ASG): case(JCTree.MINUS_ASG): case(JCTree.MUL_ASG):
260 case(JCTree.DIV_ASG): case(JCTree.MOD_ASG):
261 return getStartPos(((JCAssignOp) tree).lhs);
262 case(JCTree.OR): case(JCTree.AND): case(JCTree.BITOR):
263 case(JCTree.BITXOR): case(JCTree.BITAND): case(JCTree.EQ):
264 case(JCTree.NE): case(JCTree.LT): case(JCTree.GT):
265 case(JCTree.LE): case(JCTree.GE): case(JCTree.SL):
266 case(JCTree.SR): case(JCTree.USR): case(JCTree.PLUS):
267 case(JCTree.MINUS): case(JCTree.MUL): case(JCTree.DIV):
268 case(JCTree.MOD):
269 return getStartPos(((JCBinary) tree).lhs);
270 case(JCTree.CLASSDEF): {
271 JCClassDecl node = (JCClassDecl)tree;
272 if (node.mods.pos != Position.NOPOS)
273 return node.mods.pos;
274 break;
275 }
276 case(JCTree.CONDEXPR):
277 return getStartPos(((JCConditional) tree).cond);
278 case(JCTree.EXEC):
279 return getStartPos(((JCExpressionStatement) tree).expr);
280 case(JCTree.INDEXED):
281 return getStartPos(((JCArrayAccess) tree).indexed);
282 case(JCTree.METHODDEF): {
283 JCMethodDecl node = (JCMethodDecl)tree;
284 if (node.mods.pos != Position.NOPOS)
285 return node.mods.pos;
286 if (node.typarams.nonEmpty()) // List.nil() used for no typarams
287 return getStartPos(node.typarams.head);
288 return node.restype == null ? node.pos : getStartPos(node.restype);
289 }
290 case(JCTree.SELECT):
291 return getStartPos(((JCFieldAccess) tree).selected);
292 case(JCTree.TYPEAPPLY):
293 return getStartPos(((JCTypeApply) tree).clazz);
294 case(JCTree.TYPEARRAY):
295 return getStartPos(((JCArrayTypeTree) tree).elemtype);
296 case(JCTree.TYPETEST):
297 return getStartPos(((JCInstanceOf) tree).expr);
298 case(JCTree.POSTINC):
299 case(JCTree.POSTDEC):
300 return getStartPos(((JCUnary) tree).arg);
301 case(JCTree.VARDEF): {
302 JCVariableDecl node = (JCVariableDecl)tree;
303 if (node.mods.pos != Position.NOPOS) {
304 return node.mods.pos;
305 } else {
306 return getStartPos(node.vartype);
307 }
308 }
309 case(JCTree.ERRONEOUS): {
310 JCErroneous node = (JCErroneous)tree;
311 if (node.errs != null && node.errs.nonEmpty())
312 return getStartPos(node.errs.head);
313 }
314 }
315 return tree.pos;
316 }
317
318 /** The end position of given tree, given a table of end positions generated by the parser
319 */
320 public static int getEndPos(JCTree tree, Map<JCTree, Integer> endPositions) {
321 if (tree == null)
322 return Position.NOPOS;
323
324 if (endPositions == null) {
325 // fall back on limited info in the tree
326 return endPos(tree);
327 }
328
329 Integer mapPos = endPositions.get(tree);
330 if (mapPos != null)
331 return mapPos;
332
333 switch(tree.getTag()) {
334 case(JCTree.BITOR_ASG): case(JCTree.BITXOR_ASG): case(JCTree.BITAND_ASG):
335 case(JCTree.SL_ASG): case(JCTree.SR_ASG): case(JCTree.USR_ASG):
336 case(JCTree.PLUS_ASG): case(JCTree.MINUS_ASG): case(JCTree.MUL_ASG):
337 case(JCTree.DIV_ASG): case(JCTree.MOD_ASG):
338 return getEndPos(((JCAssignOp) tree).rhs, endPositions);
339 case(JCTree.OR): case(JCTree.AND): case(JCTree.BITOR):
340 case(JCTree.BITXOR): case(JCTree.BITAND): case(JCTree.EQ):
341 case(JCTree.NE): case(JCTree.LT): case(JCTree.GT):
342 case(JCTree.LE): case(JCTree.GE): case(JCTree.SL):
343 case(JCTree.SR): case(JCTree.USR): case(JCTree.PLUS):
344 case(JCTree.MINUS): case(JCTree.MUL): case(JCTree.DIV):
345 case(JCTree.MOD):
346 return getEndPos(((JCBinary) tree).rhs, endPositions);
347 case(JCTree.CASE):
348 return getEndPos(((JCCase) tree).stats.last(), endPositions);
349 case(JCTree.CATCH):
350 return getEndPos(((JCCatch) tree).body, endPositions);
351 case(JCTree.CONDEXPR):
352 return getEndPos(((JCConditional) tree).falsepart, endPositions);
353 case(JCTree.FORLOOP):
354 return getEndPos(((JCForLoop) tree).body, endPositions);
355 case(JCTree.FOREACHLOOP):
356 return getEndPos(((JCEnhancedForLoop) tree).body, endPositions);
357 case(JCTree.IF): {
358 JCIf node = (JCIf)tree;
359 if (node.elsepart == null) {
360 return getEndPos(node.thenpart, endPositions);
361 } else {
362 return getEndPos(node.elsepart, endPositions);
363 }
364 }
365 case(JCTree.LABELLED):
366 return getEndPos(((JCLabeledStatement) tree).body, endPositions);
367 case(JCTree.MODIFIERS):
368 return getEndPos(((JCModifiers) tree).annotations.last(), endPositions);
369 case(JCTree.SYNCHRONIZED):
370 return getEndPos(((JCSynchronized) tree).body, endPositions);
371 case(JCTree.TOPLEVEL):
372 return getEndPos(((JCCompilationUnit) tree).defs.last(), endPositions);
373 case(JCTree.TRY): {
374 JCTry node = (JCTry)tree;
375 if (node.finalizer != null) {
376 return getEndPos(node.finalizer, endPositions);
377 } else if (!node.catchers.isEmpty()) {
378 return getEndPos(node.catchers.last(), endPositions);
379 } else {
380 return getEndPos(node.body, endPositions);
381 }
382 }
383 case(JCTree.WILDCARD):
384 return getEndPos(((JCWildcard) tree).inner, endPositions);
385 case(JCTree.TYPECAST):
386 return getEndPos(((JCTypeCast) tree).expr, endPositions);
387 case(JCTree.TYPETEST):
388 return getEndPos(((JCInstanceOf) tree).clazz, endPositions);
389 case(JCTree.POS):
390 case(JCTree.NEG):
391 case(JCTree.NOT):
392 case(JCTree.COMPL):
393 case(JCTree.PREINC):
394 case(JCTree.PREDEC):
395 return getEndPos(((JCUnary) tree).arg, endPositions);
396 case(JCTree.WHILELOOP):
397 return getEndPos(((JCWhileLoop) tree).body, endPositions);
398 case(JCTree.ERRONEOUS): {
399 JCErroneous node = (JCErroneous)tree;
400 if (node.errs != null && node.errs.nonEmpty())
401 return getEndPos(node.errs.last(), endPositions);
402 }
403 }
404 return Position.NOPOS;
405 }
406
407
408 /** A DiagnosticPosition with the preferred position set to the
409 * end position of given tree, if it is a block with
410 * defined endpos.
411 */
412 public static DiagnosticPosition diagEndPos(final JCTree tree) {
413 final int endPos = TreeInfo.endPos(tree);
414 return new DiagnosticPosition() {
415 public JCTree getTree() { return tree; }
416 public int getStartPosition() { return TreeInfo.getStartPos(tree); }
417 public int getPreferredPosition() { return endPos; }
418 public int getEndPosition(Map<JCTree, Integer> endPosTable) {
419 return TreeInfo.getEndPos(tree, endPosTable);
420 }
421 };
422 }
423
424 /** The position of the finalizer of given try/synchronized statement.
425 */
426 public static int finalizerPos(JCTree tree) {
427 if (tree.getTag() == JCTree.TRY) {
428 JCTry t = (JCTry) tree;
429 assert t.finalizer != null;
430 return firstStatPos(t.finalizer);
431 } else if (tree.getTag() == JCTree.SYNCHRONIZED) {
432 return endPos(((JCSynchronized) tree).body);
433 } else {
434 throw new AssertionError();
435 }
436 }
437
438 /** Find the position for reporting an error about a symbol, where
439 * that symbol is defined somewhere in the given tree. */
440 public static int positionFor(final Symbol sym, final JCTree tree) {
441 JCTree decl = declarationFor(sym, tree);
442 return ((decl != null) ? decl : tree).pos;
443 }
444
445 /** Find the position for reporting an error about a symbol, where
446 * that symbol is defined somewhere in the given tree. */
447 public static DiagnosticPosition diagnosticPositionFor(final Symbol sym, final JCTree tree) {
448 JCTree decl = declarationFor(sym, tree);
449 return ((decl != null) ? decl : tree).pos();
450 }
451
452 /** Find the declaration for a symbol, where
453 * that symbol is defined somewhere in the given tree. */
454 public static JCTree declarationFor(final Symbol sym, final JCTree tree) {
455 class DeclScanner extends TreeScanner {
456 JCTree result = null;
457 public void scan(JCTree tree) {
458 if (tree!=null && result==null)
459 tree.accept(this);
460 }
461 public void visitTopLevel(JCCompilationUnit that) {
462 if (that.packge == sym) result = that;
463 else super.visitTopLevel(that);
464 }
465 public void visitClassDef(JCClassDecl that) {
466 if (that.sym == sym) result = that;
467 else super.visitClassDef(that);
468 }
469 public void visitMethodDef(JCMethodDecl that) {
470 if (that.sym == sym) result = that;
471 else super.visitMethodDef(that);
472 }
473 public void visitVarDef(JCVariableDecl that) {
474 if (that.sym == sym) result = that;
475 else super.visitVarDef(that);
476 }
477 }
478 DeclScanner s = new DeclScanner();
479 tree.accept(s);
480 return s.result;
481 }
482
483 public static Env<AttrContext> scopeFor(JCTree node, JCCompilationUnit unit) {
484 return scopeFor(pathFor(node, unit));
485 }
486
487 public static Env<AttrContext> scopeFor(List<JCTree> path) {
488 // TODO: not implemented yet
489 throw new UnsupportedOperationException("not implemented yet");
490 }
491
492 public static List<JCTree> pathFor(final JCTree node, final JCCompilationUnit unit) {
493 class Result extends Error {
494 static final long serialVersionUID = -5942088234594905625L;
495 List<JCTree> path;
496 Result(List<JCTree> path) {
497 this.path = path;
498 }
499 }
500 class PathFinder extends TreeScanner {
501 List<JCTree> path = List.nil();
502 public void scan(JCTree tree) {
503 if (tree != null) {
504 path = path.prepend(tree);
505 if (tree == node)
506 throw new Result(path);
507 super.scan(tree);
508 path = path.tail;
509 }
510 }
511 }
512 try {
513 new PathFinder().scan(unit);
514 } catch (Result result) {
515 return result.path;
516 }
517 return List.nil();
518 }
519
520 /** Return the statement referenced by a label.
521 * If the label refers to a loop or switch, return that switch
522 * otherwise return the labelled statement itself
523 */
524 public static JCTree referencedStatement(JCLabeledStatement tree) {
525 JCTree t = tree;
526 do t = ((JCLabeledStatement) t).body;
527 while (t.getTag() == JCTree.LABELLED);
528 switch (t.getTag()) {
529 case JCTree.DOLOOP: case JCTree.WHILELOOP: case JCTree.FORLOOP: case JCTree.FOREACHLOOP: case JCTree.SWITCH:
530 return t;
531 default:
532 return tree;
533 }
534 }
535
536 /** Skip parens and return the enclosed expression
537 */
538 public static JCExpression skipParens(JCExpression tree) {
539 while (tree.getTag() == JCTree.PARENS) {
540 tree = ((JCParens) tree).expr;
541 }
542 return tree;
543 }
544
545 /** Skip parens and return the enclosed expression
546 */
547 public static JCTree skipParens(JCTree tree) {
548 if (tree.getTag() == JCTree.PARENS)
549 return skipParens((JCParens)tree);
550 else
551 return tree;
552 }
553
554 /** Return the types of a list of trees.
555 */
556 public static List<Type> types(List<? extends JCTree> trees) {
557 ListBuffer<Type> ts = new ListBuffer<Type>();
558 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
559 ts.append(l.head.type);
560 return ts.toList();
561 }
562
563 /** If this tree is an identifier or a field or a parameterized type,
564 * return its name, otherwise return null.
565 */
566 public static Name name(JCTree tree) {
567 switch (tree.getTag()) {
568 case JCTree.IDENT:
569 return ((JCIdent) tree).name;
570 case JCTree.SELECT:
571 return ((JCFieldAccess) tree).name;
572 case JCTree.TYPEAPPLY:
573 return name(((JCTypeApply) tree).clazz);
574 default:
575 return null;
576 }
577 }
578
579 /** If this tree is a qualified identifier, its return fully qualified name,
580 * otherwise return null.
581 */
582 public static Name fullName(JCTree tree) {
583 tree = skipParens(tree);
584 switch (tree.getTag()) {
585 case JCTree.IDENT:
586 return ((JCIdent) tree).name;
587 case JCTree.SELECT:
588 Name sname = fullName(((JCFieldAccess) tree).selected);
589 return sname == null ? null : sname.append('.', name(tree));
590 default:
591 return null;
592 }
593 }
594
595 public static Symbol symbolFor(JCTree node) {
596 node = skipParens(node);
597 switch (node.getTag()) {
598 case JCTree.CLASSDEF:
599 return ((JCClassDecl) node).sym;
600 case JCTree.METHODDEF:
601 return ((JCMethodDecl) node).sym;
602 case JCTree.VARDEF:
603 return ((JCVariableDecl) node).sym;
604 default:
605 return null;
606 }
607 }
608
609 /** If this tree is an identifier or a field, return its symbol,
610 * otherwise return null.
611 */
612 public static Symbol symbol(JCTree tree) {
613 tree = skipParens(tree);
614 switch (tree.getTag()) {
615 case JCTree.IDENT:
616 return ((JCIdent) tree).sym;
617 case JCTree.SELECT:
618 return ((JCFieldAccess) tree).sym;
619 case JCTree.TYPEAPPLY:
620 return symbol(((JCTypeApply) tree).clazz);
621 default:
622 return null;
623 }
624 }
625
626 /** Return true if this is a nonstatic selection. */
627 public static boolean nonstaticSelect(JCTree tree) {
628 tree = skipParens(tree);
629 if (tree.getTag() != JCTree.SELECT) return false;
630 JCFieldAccess s = (JCFieldAccess) tree;
631 Symbol e = symbol(s.selected);
632 return e == null || (e.kind != Kinds.PCK && e.kind != Kinds.TYP);
633 }
634
635 /** If this tree is an identifier or a field, set its symbol, otherwise skip.
636 */
637 public static void setSymbol(JCTree tree, Symbol sym) {
638 tree = skipParens(tree);
639 switch (tree.getTag()) {
640 case JCTree.IDENT:
641 ((JCIdent) tree).sym = sym; break;
642 case JCTree.SELECT:
643 ((JCFieldAccess) tree).sym = sym; break;
644 default:
645 }
646 }
647
648 /** If this tree is a declaration or a block, return its flags field,
649 * otherwise return 0.
650 */
651 public static long flags(JCTree tree) {
652 switch (tree.getTag()) {
653 case JCTree.VARDEF:
654 return ((JCVariableDecl) tree).mods.flags;
655 case JCTree.METHODDEF:
656 return ((JCMethodDecl) tree).mods.flags;
657 case JCTree.CLASSDEF:
658 return ((JCClassDecl) tree).mods.flags;
659 case JCTree.BLOCK:
660 return ((JCBlock) tree).flags;
661 default:
662 return 0;
663 }
664 }
665
666 /** Return first (smallest) flag in `flags':
667 * pre: flags != 0
668 */
669 public static long firstFlag(long flags) {
670 int flag = 1;
671 while ((flag & StandardFlags) != 0 && (flag & flags) == 0)
672 flag = flag << 1;
673 return flag;
674 }
675
676 /** Return flags as a string, separated by " ".
677 */
678 public static String flagNames(long flags) {
679 return Flags.toString(flags & StandardFlags).trim();
680 }
681
682 /** Operator precedences values.
683 */
684 public static final int
685 notExpression = -1, // not an expression
686 noPrec = 0, // no enclosing expression
687 assignPrec = 1,
688 assignopPrec = 2,
689 condPrec = 3,
690 orPrec = 4,
691 andPrec = 5,
692 bitorPrec = 6,
693 bitxorPrec = 7,
694 bitandPrec = 8,
695 eqPrec = 9,
696 ordPrec = 10,
697 shiftPrec = 11,
698 addPrec = 12,
699 mulPrec = 13,
700 prefixPrec = 14,
701 postfixPrec = 15,
702 precCount = 16;
703
704
705 /** Map operators to their precedence levels.
706 */
707 public static int opPrec(int op) {
708 switch(op) {
709 case JCTree.POS:
710 case JCTree.NEG:
711 case JCTree.NOT:
712 case JCTree.COMPL:
713 case JCTree.PREINC:
714 case JCTree.PREDEC: return prefixPrec;
715 case JCTree.POSTINC:
716 case JCTree.POSTDEC:
717 case JCTree.NULLCHK: return postfixPrec;
718 case JCTree.ASSIGN: return assignPrec;
719 case JCTree.BITOR_ASG:
720 case JCTree.BITXOR_ASG:
721 case JCTree.BITAND_ASG:
722 case JCTree.SL_ASG:
723 case JCTree.SR_ASG:
724 case JCTree.USR_ASG:
725 case JCTree.PLUS_ASG:
726 case JCTree.MINUS_ASG:
727 case JCTree.MUL_ASG:
728 case JCTree.DIV_ASG:
729 case JCTree.MOD_ASG: return assignopPrec;
730 case JCTree.OR: return orPrec;
731 case JCTree.AND: return andPrec;
732 case JCTree.EQ:
733 case JCTree.NE: return eqPrec;
734 case JCTree.LT:
735 case JCTree.GT:
736 case JCTree.LE:
737 case JCTree.GE: return ordPrec;
738 case JCTree.BITOR: return bitorPrec;
739 case JCTree.BITXOR: return bitxorPrec;
740 case JCTree.BITAND: return bitandPrec;
741 case JCTree.SL:
742 case JCTree.SR:
743 case JCTree.USR: return shiftPrec;
744 case JCTree.PLUS:
745 case JCTree.MINUS: return addPrec;
746 case JCTree.MUL:
747 case JCTree.DIV:
748 case JCTree.MOD: return mulPrec;
749 case JCTree.TYPETEST: return ordPrec;
750 default: throw new AssertionError();
751 }
752 }
753
754 static Tree.Kind tagToKind(int tag) {
755 switch (tag) {
756 // Postfix expressions
757 case JCTree.POSTINC: // _ ++
758 return Tree.Kind.POSTFIX_INCREMENT;
759 case JCTree.POSTDEC: // _ --
760 return Tree.Kind.POSTFIX_DECREMENT;
761
762 // Unary operators
763 case JCTree.PREINC: // ++ _
764 return Tree.Kind.PREFIX_INCREMENT;
765 case JCTree.PREDEC: // -- _
766 return Tree.Kind.PREFIX_DECREMENT;
767 case JCTree.POS: // +
768 return Tree.Kind.UNARY_PLUS;
769 case JCTree.NEG: // -
770 return Tree.Kind.UNARY_MINUS;
771 case JCTree.COMPL: // ~
772 return Tree.Kind.BITWISE_COMPLEMENT;
773 case JCTree.NOT: // !
774 return Tree.Kind.LOGICAL_COMPLEMENT;
775
776 // Binary operators
777
778 // Multiplicative operators
779 case JCTree.MUL: // *
780 return Tree.Kind.MULTIPLY;
781 case JCTree.DIV: // /
782 return Tree.Kind.DIVIDE;
783 case JCTree.MOD: // %
784 return Tree.Kind.REMAINDER;
785
786 // Additive operators
787 case JCTree.PLUS: // +
788 return Tree.Kind.PLUS;
789 case JCTree.MINUS: // -
790 return Tree.Kind.MINUS;
791
792 // Shift operators
793 case JCTree.SL: // <<
794 return Tree.Kind.LEFT_SHIFT;
795 case JCTree.SR: // >>
796 return Tree.Kind.RIGHT_SHIFT;
797 case JCTree.USR: // >>>
798 return Tree.Kind.UNSIGNED_RIGHT_SHIFT;
799
800 // Relational operators
801 case JCTree.LT: // <
802 return Tree.Kind.LESS_THAN;
803 case JCTree.GT: // >
804 return Tree.Kind.GREATER_THAN;
805 case JCTree.LE: // <=
806 return Tree.Kind.LESS_THAN_EQUAL;
807 case JCTree.GE: // >=
808 return Tree.Kind.GREATER_THAN_EQUAL;
809
810 // Equality operators
811 case JCTree.EQ: // ==
812 return Tree.Kind.EQUAL_TO;
813 case JCTree.NE: // !=
814 return Tree.Kind.NOT_EQUAL_TO;
815
816 // Bitwise and logical operators
817 case JCTree.BITAND: // &
818 return Tree.Kind.AND;
819 case JCTree.BITXOR: // ^
820 return Tree.Kind.XOR;
821 case JCTree.BITOR: // |
822 return Tree.Kind.OR;
823
824 // Conditional operators
825 case JCTree.AND: // &&
826 return Tree.Kind.CONDITIONAL_AND;
827 case JCTree.OR: // ||
828 return Tree.Kind.CONDITIONAL_OR;
829
830 // Assignment operators
831 case JCTree.MUL_ASG: // *=
832 return Tree.Kind.MULTIPLY_ASSIGNMENT;
833 case JCTree.DIV_ASG: // /=
834 return Tree.Kind.DIVIDE_ASSIGNMENT;
835 case JCTree.MOD_ASG: // %=
836 return Tree.Kind.REMAINDER_ASSIGNMENT;
837 case JCTree.PLUS_ASG: // +=
838 return Tree.Kind.PLUS_ASSIGNMENT;
839 case JCTree.MINUS_ASG: // -=
840 return Tree.Kind.MINUS_ASSIGNMENT;
841 case JCTree.SL_ASG: // <<=
842 return Tree.Kind.LEFT_SHIFT_ASSIGNMENT;
843 case JCTree.SR_ASG: // >>=
844 return Tree.Kind.RIGHT_SHIFT_ASSIGNMENT;
845 case JCTree.USR_ASG: // >>>=
846 return Tree.Kind.UNSIGNED_RIGHT_SHIFT_ASSIGNMENT;
847 case JCTree.BITAND_ASG: // &=
848 return Tree.Kind.AND_ASSIGNMENT;
849 case JCTree.BITXOR_ASG: // ^=
850 return Tree.Kind.XOR_ASSIGNMENT;
851 case JCTree.BITOR_ASG: // |=
852 return Tree.Kind.OR_ASSIGNMENT;
853
854 // Null check (implementation detail), for example, __.getClass()
855 case JCTree.NULLCHK:
856 return Tree.Kind.OTHER;
857
858 default:
859 return null;
860 }
861 }
862 }