duke@1: /*
xdono@117:  * Copyright 1999-2008 Sun Microsystems, Inc.  All Rights Reserved.
duke@1:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@1:  *
duke@1:  * This code is free software; you can redistribute it and/or modify it
duke@1:  * under the terms of the GNU General Public License version 2 only, as
duke@1:  * published by the Free Software Foundation.  Sun designates this
duke@1:  * particular file as subject to the "Classpath" exception as provided
duke@1:  * by Sun in the LICENSE file that accompanied this code.
duke@1:  *
duke@1:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@1:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@1:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@1:  * version 2 for more details (a copy is included in the LICENSE file that
duke@1:  * accompanied this code).
duke@1:  *
duke@1:  * You should have received a copy of the GNU General Public License version
duke@1:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@1:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@1:  *
duke@1:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@1:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@1:  * have any questions.
duke@1:  */
duke@1: 
duke@1: package com.sun.tools.javac.tree;
duke@1: 
duke@1: import com.sun.source.tree.Tree;
duke@1: import com.sun.tools.javac.comp.AttrContext;
duke@1: import com.sun.tools.javac.comp.Env;
duke@1: import java.util.Map;
duke@1: import com.sun.tools.javac.util.*;
duke@1: import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
duke@1: import com.sun.tools.javac.code.*;
duke@1: import com.sun.tools.javac.tree.JCTree.*;
duke@1: 
duke@1: import static com.sun.tools.javac.code.Flags.*;
duke@1: 
duke@1: /** Utility class containing inspector methods for trees.
duke@1:  *
duke@1:  *  <p><b>This is NOT part of any API supported by Sun Microsystems.  If
duke@1:  *  you write code that depends on this, you do so at your own risk.
duke@1:  *  This code and its internal interfaces are subject to change or
duke@1:  *  deletion without notice.</b>
duke@1:  */
duke@1: public class TreeInfo {
duke@1:     protected static final Context.Key<TreeInfo> treeInfoKey =
duke@1:         new Context.Key<TreeInfo>();
duke@1: 
duke@1:     public static TreeInfo instance(Context context) {
duke@1:         TreeInfo instance = context.get(treeInfoKey);
duke@1:         if (instance == null)
duke@1:             instance = new TreeInfo(context);
duke@1:         return instance;
duke@1:     }
duke@1: 
duke@1:     /** The names of all operators.
duke@1:      */
duke@1:     private Name[] opname = new Name[JCTree.MOD - JCTree.POS + 1];
duke@1: 
duke@1:     private TreeInfo(Context context) {
duke@1:         context.put(treeInfoKey, this);
duke@1: 
jjg@113:         Names names = Names.instance(context);
duke@1:         opname[JCTree.POS     - JCTree.POS] = names.fromString("+");
duke@1:         opname[JCTree.NEG     - JCTree.POS] = names.hyphen;
duke@1:         opname[JCTree.NOT     - JCTree.POS] = names.fromString("!");
duke@1:         opname[JCTree.COMPL   - JCTree.POS] = names.fromString("~");
duke@1:         opname[JCTree.PREINC  - JCTree.POS] = names.fromString("++");
duke@1:         opname[JCTree.PREDEC  - JCTree.POS] = names.fromString("--");
duke@1:         opname[JCTree.POSTINC - JCTree.POS] = names.fromString("++");
duke@1:         opname[JCTree.POSTDEC - JCTree.POS] = names.fromString("--");
duke@1:         opname[JCTree.NULLCHK - JCTree.POS] = names.fromString("<*nullchk*>");
duke@1:         opname[JCTree.OR      - JCTree.POS] = names.fromString("||");
duke@1:         opname[JCTree.AND     - JCTree.POS] = names.fromString("&&");
duke@1:         opname[JCTree.EQ      - JCTree.POS] = names.fromString("==");
duke@1:         opname[JCTree.NE      - JCTree.POS] = names.fromString("!=");
duke@1:         opname[JCTree.LT      - JCTree.POS] = names.fromString("<");
duke@1:         opname[JCTree.GT      - JCTree.POS] = names.fromString(">");
duke@1:         opname[JCTree.LE      - JCTree.POS] = names.fromString("<=");
duke@1:         opname[JCTree.GE      - JCTree.POS] = names.fromString(">=");
duke@1:         opname[JCTree.BITOR   - JCTree.POS] = names.fromString("|");
duke@1:         opname[JCTree.BITXOR  - JCTree.POS] = names.fromString("^");
duke@1:         opname[JCTree.BITAND  - JCTree.POS] = names.fromString("&");
duke@1:         opname[JCTree.SL      - JCTree.POS] = names.fromString("<<");
duke@1:         opname[JCTree.SR      - JCTree.POS] = names.fromString(">>");
duke@1:         opname[JCTree.USR     - JCTree.POS] = names.fromString(">>>");
duke@1:         opname[JCTree.PLUS    - JCTree.POS] = names.fromString("+");
duke@1:         opname[JCTree.MINUS   - JCTree.POS] = names.hyphen;
duke@1:         opname[JCTree.MUL     - JCTree.POS] = names.asterisk;
duke@1:         opname[JCTree.DIV     - JCTree.POS] = names.slash;
duke@1:         opname[JCTree.MOD     - JCTree.POS] = names.fromString("%");
duke@1:     }
duke@1: 
duke@1: 
duke@1:     /** Return name of operator with given tree tag.
duke@1:      */
duke@1:     public Name operatorName(int tag) {
duke@1:         return opname[tag - JCTree.POS];
duke@1:     }
duke@1: 
duke@1:     /** Is tree a constructor declaration?
duke@1:      */
duke@1:     public static boolean isConstructor(JCTree tree) {
duke@1:         if (tree.getTag() == JCTree.METHODDEF) {
duke@1:             Name name = ((JCMethodDecl) tree).name;
jjg@113:             return name == name.table.names.init;
duke@1:         } else {
duke@1:             return false;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** Is there a constructor declaration in the given list of trees?
duke@1:      */
duke@1:     public static boolean hasConstructors(List<JCTree> trees) {
duke@1:         for (List<JCTree> l = trees; l.nonEmpty(); l = l.tail)
duke@1:             if (isConstructor(l.head)) return true;
duke@1:         return false;
duke@1:     }
duke@1: 
duke@1:     /** Is statement an initializer for a synthetic field?
duke@1:      */
duke@1:     public static boolean isSyntheticInit(JCTree stat) {
duke@1:         if (stat.getTag() == JCTree.EXEC) {
duke@1:             JCExpressionStatement exec = (JCExpressionStatement)stat;
duke@1:             if (exec.expr.getTag() == JCTree.ASSIGN) {
duke@1:                 JCAssign assign = (JCAssign)exec.expr;
duke@1:                 if (assign.lhs.getTag() == JCTree.SELECT) {
duke@1:                     JCFieldAccess select = (JCFieldAccess)assign.lhs;
duke@1:                     if (select.sym != null &&
duke@1:                         (select.sym.flags() & SYNTHETIC) != 0) {
duke@1:                         Name selected = name(select.selected);
jjg@113:                         if (selected != null && selected == selected.table.names._this)
duke@1:                             return true;
duke@1:                     }
duke@1:                 }
duke@1:             }
duke@1:         }
duke@1:         return false;
duke@1:     }
duke@1: 
duke@1:     /** If the expression is a method call, return the method name, null
duke@1:      *  otherwise. */
duke@1:     public static Name calledMethodName(JCTree tree) {
duke@1:         if (tree.getTag() == JCTree.EXEC) {
duke@1:             JCExpressionStatement exec = (JCExpressionStatement)tree;
duke@1:             if (exec.expr.getTag() == JCTree.APPLY) {
duke@1:                 Name mname = TreeInfo.name(((JCMethodInvocation) exec.expr).meth);
duke@1:                 return mname;
duke@1:             }
duke@1:         }
duke@1:         return null;
duke@1:     }
duke@1: 
duke@1:     /** Is this a call to this or super?
duke@1:      */
duke@1:     public static boolean isSelfCall(JCTree tree) {
duke@1:         Name name = calledMethodName(tree);
duke@1:         if (name != null) {
jjg@113:             Names names = name.table.names;
duke@1:             return name==names._this || name==names._super;
duke@1:         } else {
duke@1:             return false;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** Is this a call to super?
duke@1:      */
duke@1:     public static boolean isSuperCall(JCTree tree) {
duke@1:         Name name = calledMethodName(tree);
duke@1:         if (name != null) {
jjg@113:             Names names = name.table.names;
duke@1:             return name==names._super;
duke@1:         } else {
duke@1:             return false;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** Is this a constructor whose first (non-synthetic) statement is not
duke@1:      *  of the form this(...)?
duke@1:      */
duke@1:     public static boolean isInitialConstructor(JCTree tree) {
duke@1:         JCMethodInvocation app = firstConstructorCall(tree);
duke@1:         if (app == null) return false;
duke@1:         Name meth = name(app.meth);
jjg@113:         return meth == null || meth != meth.table.names._this;
duke@1:     }
duke@1: 
duke@1:     /** Return the first call in a constructor definition. */
duke@1:     public static JCMethodInvocation firstConstructorCall(JCTree tree) {
duke@1:         if (tree.getTag() != JCTree.METHODDEF) return null;
duke@1:         JCMethodDecl md = (JCMethodDecl) tree;
jjg@113:         Names names = md.name.table.names;
duke@1:         if (md.name != names.init) return null;
duke@1:         if (md.body == null) return null;
duke@1:         List<JCStatement> stats = md.body.stats;
duke@1:         // Synthetic initializations can appear before the super call.
duke@1:         while (stats.nonEmpty() && isSyntheticInit(stats.head))
duke@1:             stats = stats.tail;
duke@1:         if (stats.isEmpty()) return null;
duke@1:         if (stats.head.getTag() != JCTree.EXEC) return null;
duke@1:         JCExpressionStatement exec = (JCExpressionStatement) stats.head;
duke@1:         if (exec.expr.getTag() != JCTree.APPLY) return null;
duke@1:         return (JCMethodInvocation)exec.expr;
duke@1:     }
duke@1: 
mcimadamore@537:     /** Return true if a tree represents a diamond new expr. */
mcimadamore@537:     public static boolean isDiamond(JCTree tree) {
mcimadamore@537:         switch(tree.getTag()) {
mcimadamore@537:             case JCTree.TYPEAPPLY: return ((JCTypeApply)tree).getTypeArguments().isEmpty();
mcimadamore@537:             case JCTree.NEWCLASS: return isDiamond(((JCNewClass)tree).clazz);
mcimadamore@537:             default: return false;
mcimadamore@537:         }
mcimadamore@537:     }
mcimadamore@537: 
duke@1:     /** Return true if a tree represents the null literal. */
duke@1:     public static boolean isNull(JCTree tree) {
duke@1:         if (tree.getTag() != JCTree.LITERAL)
duke@1:             return false;
duke@1:         JCLiteral lit = (JCLiteral) tree;
duke@1:         return (lit.typetag == TypeTags.BOT);
duke@1:     }
duke@1: 
duke@1:     /** The position of the first statement in a block, or the position of
duke@1:      *  the block itself if it is empty.
duke@1:      */
duke@1:     public static int firstStatPos(JCTree tree) {
duke@1:         if (tree.getTag() == JCTree.BLOCK && ((JCBlock) tree).stats.nonEmpty())
duke@1:             return ((JCBlock) tree).stats.head.pos;
duke@1:         else
duke@1:             return tree.pos;
duke@1:     }
duke@1: 
duke@1:     /** The end position of given tree, if it is a block with
duke@1:      *  defined endpos.
duke@1:      */
duke@1:     public static int endPos(JCTree tree) {
duke@1:         if (tree.getTag() == JCTree.BLOCK && ((JCBlock) tree).endpos != Position.NOPOS)
duke@1:             return ((JCBlock) tree).endpos;
duke@1:         else if (tree.getTag() == JCTree.SYNCHRONIZED)
duke@1:             return endPos(((JCSynchronized) tree).body);
duke@1:         else if (tree.getTag() == JCTree.TRY) {
duke@1:             JCTry t = (JCTry) tree;
duke@1:             return endPos((t.finalizer != null)
duke@1:                           ? t.finalizer
duke@1:                           : t.catchers.last().body);
duke@1:         } else
duke@1:             return tree.pos;
duke@1:     }
duke@1: 
duke@1: 
duke@1:     /** Get the start position for a tree node.  The start position is
duke@1:      * defined to be the position of the first character of the first
duke@1:      * token of the node's source text.
duke@1:      * @param tree  The tree node
duke@1:      */
duke@1:     public static int getStartPos(JCTree tree) {
duke@1:         if (tree == null)
duke@1:             return Position.NOPOS;
duke@1: 
duke@1:         switch(tree.getTag()) {
duke@1:         case(JCTree.APPLY):
duke@1:             return getStartPos(((JCMethodInvocation) tree).meth);
duke@1:         case(JCTree.ASSIGN):
duke@1:             return getStartPos(((JCAssign) tree).lhs);
duke@1:         case(JCTree.BITOR_ASG): case(JCTree.BITXOR_ASG): case(JCTree.BITAND_ASG):
duke@1:         case(JCTree.SL_ASG): case(JCTree.SR_ASG): case(JCTree.USR_ASG):
duke@1:         case(JCTree.PLUS_ASG): case(JCTree.MINUS_ASG): case(JCTree.MUL_ASG):
duke@1:         case(JCTree.DIV_ASG): case(JCTree.MOD_ASG):
duke@1:             return getStartPos(((JCAssignOp) tree).lhs);
duke@1:         case(JCTree.OR): case(JCTree.AND): case(JCTree.BITOR):
duke@1:         case(JCTree.BITXOR): case(JCTree.BITAND): case(JCTree.EQ):
duke@1:         case(JCTree.NE): case(JCTree.LT): case(JCTree.GT):
duke@1:         case(JCTree.LE): case(JCTree.GE): case(JCTree.SL):
duke@1:         case(JCTree.SR): case(JCTree.USR): case(JCTree.PLUS):
duke@1:         case(JCTree.MINUS): case(JCTree.MUL): case(JCTree.DIV):
duke@1:         case(JCTree.MOD):
duke@1:             return getStartPos(((JCBinary) tree).lhs);
duke@1:         case(JCTree.CLASSDEF): {
duke@1:             JCClassDecl node = (JCClassDecl)tree;
duke@1:             if (node.mods.pos != Position.NOPOS)
duke@1:                 return node.mods.pos;
duke@1:             break;
duke@1:         }
duke@1:         case(JCTree.CONDEXPR):
duke@1:             return getStartPos(((JCConditional) tree).cond);
duke@1:         case(JCTree.EXEC):
duke@1:             return getStartPos(((JCExpressionStatement) tree).expr);
duke@1:         case(JCTree.INDEXED):
duke@1:             return getStartPos(((JCArrayAccess) tree).indexed);
duke@1:         case(JCTree.METHODDEF): {
duke@1:             JCMethodDecl node = (JCMethodDecl)tree;
duke@1:             if (node.mods.pos != Position.NOPOS)
duke@1:                 return node.mods.pos;
duke@1:             if (node.typarams.nonEmpty()) // List.nil() used for no typarams
duke@1:                 return getStartPos(node.typarams.head);
duke@1:             return node.restype == null ? node.pos : getStartPos(node.restype);
duke@1:         }
duke@1:         case(JCTree.SELECT):
duke@1:             return getStartPos(((JCFieldAccess) tree).selected);
duke@1:         case(JCTree.TYPEAPPLY):
duke@1:             return getStartPos(((JCTypeApply) tree).clazz);
duke@1:         case(JCTree.TYPEARRAY):
duke@1:             return getStartPos(((JCArrayTypeTree) tree).elemtype);
duke@1:         case(JCTree.TYPETEST):
duke@1:             return getStartPos(((JCInstanceOf) tree).expr);
duke@1:         case(JCTree.POSTINC):
duke@1:         case(JCTree.POSTDEC):
duke@1:             return getStartPos(((JCUnary) tree).arg);
jjg@482:         case(JCTree.ANNOTATED_TYPE): {
jjg@482:             JCAnnotatedType node = (JCAnnotatedType) tree;
jjg@482:             if (node.annotations.nonEmpty())
jjg@482:                 return getStartPos(node.annotations.head);
jjg@482:             return getStartPos(node.underlyingType);
jjg@482:         }
jjg@482:         case(JCTree.NEWCLASS): {
jjg@482:             JCNewClass node = (JCNewClass)tree;
jjg@482:             if (node.encl != null)
jjg@482:                 return getStartPos(node.encl);
jjg@482:             break;
jjg@482:         }
duke@1:         case(JCTree.VARDEF): {
duke@1:             JCVariableDecl node = (JCVariableDecl)tree;
duke@1:             if (node.mods.pos != Position.NOPOS) {
duke@1:                 return node.mods.pos;
duke@1:             } else {
duke@1:                 return getStartPos(node.vartype);
duke@1:             }
duke@1:         }
duke@1:         case(JCTree.ERRONEOUS): {
duke@1:             JCErroneous node = (JCErroneous)tree;
duke@1:             if (node.errs != null && node.errs.nonEmpty())
duke@1:                 return getStartPos(node.errs.head);
duke@1:         }
duke@1:         }
duke@1:         return tree.pos;
duke@1:     }
duke@1: 
duke@1:     /** The end position of given tree, given  a table of end positions generated by the parser
duke@1:      */
duke@1:     public static int getEndPos(JCTree tree, Map<JCTree, Integer> endPositions) {
duke@1:         if (tree == null)
duke@1:             return Position.NOPOS;
duke@1: 
duke@1:         if (endPositions == null) {
duke@1:             // fall back on limited info in the tree
duke@1:             return endPos(tree);
duke@1:         }
duke@1: 
duke@1:         Integer mapPos = endPositions.get(tree);
duke@1:         if (mapPos != null)
duke@1:             return mapPos;
duke@1: 
duke@1:         switch(tree.getTag()) {
duke@1:         case(JCTree.BITOR_ASG): case(JCTree.BITXOR_ASG): case(JCTree.BITAND_ASG):
duke@1:         case(JCTree.SL_ASG): case(JCTree.SR_ASG): case(JCTree.USR_ASG):
duke@1:         case(JCTree.PLUS_ASG): case(JCTree.MINUS_ASG): case(JCTree.MUL_ASG):
duke@1:         case(JCTree.DIV_ASG): case(JCTree.MOD_ASG):
duke@1:             return getEndPos(((JCAssignOp) tree).rhs, endPositions);
duke@1:         case(JCTree.OR): case(JCTree.AND): case(JCTree.BITOR):
duke@1:         case(JCTree.BITXOR): case(JCTree.BITAND): case(JCTree.EQ):
duke@1:         case(JCTree.NE): case(JCTree.LT): case(JCTree.GT):
duke@1:         case(JCTree.LE): case(JCTree.GE): case(JCTree.SL):
duke@1:         case(JCTree.SR): case(JCTree.USR): case(JCTree.PLUS):
duke@1:         case(JCTree.MINUS): case(JCTree.MUL): case(JCTree.DIV):
duke@1:         case(JCTree.MOD):
duke@1:             return getEndPos(((JCBinary) tree).rhs, endPositions);
duke@1:         case(JCTree.CASE):
duke@1:             return getEndPos(((JCCase) tree).stats.last(), endPositions);
duke@1:         case(JCTree.CATCH):
duke@1:             return getEndPos(((JCCatch) tree).body, endPositions);
duke@1:         case(JCTree.CONDEXPR):
duke@1:             return getEndPos(((JCConditional) tree).falsepart, endPositions);
duke@1:         case(JCTree.FORLOOP):
duke@1:             return getEndPos(((JCForLoop) tree).body, endPositions);
duke@1:         case(JCTree.FOREACHLOOP):
duke@1:             return getEndPos(((JCEnhancedForLoop) tree).body, endPositions);
duke@1:         case(JCTree.IF): {
duke@1:             JCIf node = (JCIf)tree;
duke@1:             if (node.elsepart == null) {
duke@1:                 return getEndPos(node.thenpart, endPositions);
duke@1:             } else {
duke@1:                 return getEndPos(node.elsepart, endPositions);
duke@1:             }
duke@1:         }
duke@1:         case(JCTree.LABELLED):
duke@1:             return getEndPos(((JCLabeledStatement) tree).body, endPositions);
duke@1:         case(JCTree.MODIFIERS):
duke@1:             return getEndPos(((JCModifiers) tree).annotations.last(), endPositions);
duke@1:         case(JCTree.SYNCHRONIZED):
duke@1:             return getEndPos(((JCSynchronized) tree).body, endPositions);
duke@1:         case(JCTree.TOPLEVEL):
duke@1:             return getEndPos(((JCCompilationUnit) tree).defs.last(), endPositions);
duke@1:         case(JCTree.TRY): {
duke@1:             JCTry node = (JCTry)tree;
duke@1:             if (node.finalizer != null) {
duke@1:                 return getEndPos(node.finalizer, endPositions);
duke@1:             } else if (!node.catchers.isEmpty()) {
duke@1:                 return getEndPos(node.catchers.last(), endPositions);
duke@1:             } else {
duke@1:                 return getEndPos(node.body, endPositions);
duke@1:             }
duke@1:         }
duke@1:         case(JCTree.WILDCARD):
duke@1:             return getEndPos(((JCWildcard) tree).inner, endPositions);
duke@1:         case(JCTree.TYPECAST):
duke@1:             return getEndPos(((JCTypeCast) tree).expr, endPositions);
duke@1:         case(JCTree.TYPETEST):
duke@1:             return getEndPos(((JCInstanceOf) tree).clazz, endPositions);
duke@1:         case(JCTree.POS):
duke@1:         case(JCTree.NEG):
duke@1:         case(JCTree.NOT):
duke@1:         case(JCTree.COMPL):
duke@1:         case(JCTree.PREINC):
duke@1:         case(JCTree.PREDEC):
duke@1:             return getEndPos(((JCUnary) tree).arg, endPositions);
duke@1:         case(JCTree.WHILELOOP):
duke@1:             return getEndPos(((JCWhileLoop) tree).body, endPositions);
jjg@482:         case(JCTree.ANNOTATED_TYPE):
jjg@482:             return getEndPos(((JCAnnotatedType) tree).underlyingType, endPositions);
duke@1:         case(JCTree.ERRONEOUS): {
duke@1:             JCErroneous node = (JCErroneous)tree;
duke@1:             if (node.errs != null && node.errs.nonEmpty())
duke@1:                 return getEndPos(node.errs.last(), endPositions);
duke@1:         }
duke@1:         }
duke@1:         return Position.NOPOS;
duke@1:     }
duke@1: 
duke@1: 
duke@1:     /** A DiagnosticPosition with the preferred position set to the
duke@1:      *  end position of given tree, if it is a block with
duke@1:      *  defined endpos.
duke@1:      */
duke@1:     public static DiagnosticPosition diagEndPos(final JCTree tree) {
duke@1:         final int endPos = TreeInfo.endPos(tree);
duke@1:         return new DiagnosticPosition() {
duke@1:             public JCTree getTree() { return tree; }
duke@1:             public int getStartPosition() { return TreeInfo.getStartPos(tree); }
duke@1:             public int getPreferredPosition() { return endPos; }
duke@1:             public int getEndPosition(Map<JCTree, Integer> endPosTable) {
duke@1:                 return TreeInfo.getEndPos(tree, endPosTable);
duke@1:             }
duke@1:         };
duke@1:     }
duke@1: 
duke@1:     /** The position of the finalizer of given try/synchronized statement.
duke@1:      */
duke@1:     public static int finalizerPos(JCTree tree) {
duke@1:         if (tree.getTag() == JCTree.TRY) {
duke@1:             JCTry t = (JCTry) tree;
duke@1:             assert t.finalizer != null;
duke@1:             return firstStatPos(t.finalizer);
duke@1:         } else if (tree.getTag() == JCTree.SYNCHRONIZED) {
duke@1:             return endPos(((JCSynchronized) tree).body);
duke@1:         } else {
duke@1:             throw new AssertionError();
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** Find the position for reporting an error about a symbol, where
duke@1:      *  that symbol is defined somewhere in the given tree. */
duke@1:     public static int positionFor(final Symbol sym, final JCTree tree) {
duke@1:         JCTree decl = declarationFor(sym, tree);
duke@1:         return ((decl != null) ? decl : tree).pos;
duke@1:     }
duke@1: 
duke@1:     /** Find the position for reporting an error about a symbol, where
duke@1:      *  that symbol is defined somewhere in the given tree. */
duke@1:     public static DiagnosticPosition diagnosticPositionFor(final Symbol sym, final JCTree tree) {
duke@1:         JCTree decl = declarationFor(sym, tree);
duke@1:         return ((decl != null) ? decl : tree).pos();
duke@1:     }
duke@1: 
duke@1:     /** Find the declaration for a symbol, where
duke@1:      *  that symbol is defined somewhere in the given tree. */
duke@1:     public static JCTree declarationFor(final Symbol sym, final JCTree tree) {
duke@1:         class DeclScanner extends TreeScanner {
duke@1:             JCTree result = null;
duke@1:             public void scan(JCTree tree) {
duke@1:                 if (tree!=null && result==null)
duke@1:                     tree.accept(this);
duke@1:             }
duke@1:             public void visitTopLevel(JCCompilationUnit that) {
duke@1:                 if (that.packge == sym) result = that;
duke@1:                 else super.visitTopLevel(that);
duke@1:             }
duke@1:             public void visitClassDef(JCClassDecl that) {
duke@1:                 if (that.sym == sym) result = that;
duke@1:                 else super.visitClassDef(that);
duke@1:             }
duke@1:             public void visitMethodDef(JCMethodDecl that) {
duke@1:                 if (that.sym == sym) result = that;
duke@1:                 else super.visitMethodDef(that);
duke@1:             }
duke@1:             public void visitVarDef(JCVariableDecl that) {
duke@1:                 if (that.sym == sym) result = that;
duke@1:                 else super.visitVarDef(that);
duke@1:             }
duke@1:         }
duke@1:         DeclScanner s = new DeclScanner();
duke@1:         tree.accept(s);
duke@1:         return s.result;
duke@1:     }
duke@1: 
duke@1:     public static Env<AttrContext> scopeFor(JCTree node, JCCompilationUnit unit) {
duke@1:         return scopeFor(pathFor(node, unit));
duke@1:     }
duke@1: 
duke@1:     public static Env<AttrContext> scopeFor(List<JCTree> path) {
duke@1:         // TODO: not implemented yet
duke@1:         throw new UnsupportedOperationException("not implemented yet");
duke@1:     }
duke@1: 
duke@1:     public static List<JCTree> pathFor(final JCTree node, final JCCompilationUnit unit) {
duke@1:         class Result extends Error {
duke@1:             static final long serialVersionUID = -5942088234594905625L;
duke@1:             List<JCTree> path;
duke@1:             Result(List<JCTree> path) {
duke@1:                 this.path = path;
duke@1:             }
duke@1:         }
duke@1:         class PathFinder extends TreeScanner {
duke@1:             List<JCTree> path = List.nil();
duke@1:             public void scan(JCTree tree) {
duke@1:                 if (tree != null) {
duke@1:                     path = path.prepend(tree);
duke@1:                     if (tree == node)
duke@1:                         throw new Result(path);
duke@1:                     super.scan(tree);
duke@1:                     path = path.tail;
duke@1:                 }
duke@1:             }
duke@1:         }
duke@1:         try {
duke@1:             new PathFinder().scan(unit);
duke@1:         } catch (Result result) {
duke@1:             return result.path;
duke@1:         }
duke@1:         return List.nil();
duke@1:     }
duke@1: 
duke@1:     /** Return the statement referenced by a label.
duke@1:      *  If the label refers to a loop or switch, return that switch
duke@1:      *  otherwise return the labelled statement itself
duke@1:      */
duke@1:     public static JCTree referencedStatement(JCLabeledStatement tree) {
duke@1:         JCTree t = tree;
duke@1:         do t = ((JCLabeledStatement) t).body;
duke@1:         while (t.getTag() == JCTree.LABELLED);
duke@1:         switch (t.getTag()) {
duke@1:         case JCTree.DOLOOP: case JCTree.WHILELOOP: case JCTree.FORLOOP: case JCTree.FOREACHLOOP: case JCTree.SWITCH:
duke@1:             return t;
duke@1:         default:
duke@1:             return tree;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** Skip parens and return the enclosed expression
duke@1:      */
duke@1:     public static JCExpression skipParens(JCExpression tree) {
duke@1:         while (tree.getTag() == JCTree.PARENS) {
duke@1:             tree = ((JCParens) tree).expr;
duke@1:         }
duke@1:         return tree;
duke@1:     }
duke@1: 
duke@1:     /** Skip parens and return the enclosed expression
duke@1:      */
duke@1:     public static JCTree skipParens(JCTree tree) {
duke@1:         if (tree.getTag() == JCTree.PARENS)
duke@1:             return skipParens((JCParens)tree);
duke@1:         else
duke@1:             return tree;
duke@1:     }
duke@1: 
duke@1:     /** Return the types of a list of trees.
duke@1:      */
duke@1:     public static List<Type> types(List<? extends JCTree> trees) {
duke@1:         ListBuffer<Type> ts = new ListBuffer<Type>();
duke@1:         for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
duke@1:             ts.append(l.head.type);
duke@1:         return ts.toList();
duke@1:     }
duke@1: 
duke@1:     /** If this tree is an identifier or a field or a parameterized type,
duke@1:      *  return its name, otherwise return null.
duke@1:      */
duke@1:     public static Name name(JCTree tree) {
duke@1:         switch (tree.getTag()) {
duke@1:         case JCTree.IDENT:
duke@1:             return ((JCIdent) tree).name;
duke@1:         case JCTree.SELECT:
duke@1:             return ((JCFieldAccess) tree).name;
duke@1:         case JCTree.TYPEAPPLY:
duke@1:             return name(((JCTypeApply) tree).clazz);
duke@1:         default:
duke@1:             return null;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** If this tree is a qualified identifier, its return fully qualified name,
duke@1:      *  otherwise return null.
duke@1:      */
duke@1:     public static Name fullName(JCTree tree) {
duke@1:         tree = skipParens(tree);
duke@1:         switch (tree.getTag()) {
duke@1:         case JCTree.IDENT:
duke@1:             return ((JCIdent) tree).name;
duke@1:         case JCTree.SELECT:
duke@1:             Name sname = fullName(((JCFieldAccess) tree).selected);
duke@1:             return sname == null ? null : sname.append('.', name(tree));
duke@1:         default:
duke@1:             return null;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     public static Symbol symbolFor(JCTree node) {
duke@1:         node = skipParens(node);
duke@1:         switch (node.getTag()) {
duke@1:         case JCTree.CLASSDEF:
duke@1:             return ((JCClassDecl) node).sym;
duke@1:         case JCTree.METHODDEF:
duke@1:             return ((JCMethodDecl) node).sym;
duke@1:         case JCTree.VARDEF:
duke@1:             return ((JCVariableDecl) node).sym;
duke@1:         default:
duke@1:             return null;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** If this tree is an identifier or a field, return its symbol,
duke@1:      *  otherwise return null.
duke@1:      */
duke@1:     public static Symbol symbol(JCTree tree) {
duke@1:         tree = skipParens(tree);
duke@1:         switch (tree.getTag()) {
duke@1:         case JCTree.IDENT:
duke@1:             return ((JCIdent) tree).sym;
duke@1:         case JCTree.SELECT:
duke@1:             return ((JCFieldAccess) tree).sym;
duke@1:         case JCTree.TYPEAPPLY:
duke@1:             return symbol(((JCTypeApply) tree).clazz);
duke@1:         default:
duke@1:             return null;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** Return true if this is a nonstatic selection. */
duke@1:     public static boolean nonstaticSelect(JCTree tree) {
duke@1:         tree = skipParens(tree);
duke@1:         if (tree.getTag() != JCTree.SELECT) return false;
duke@1:         JCFieldAccess s = (JCFieldAccess) tree;
duke@1:         Symbol e = symbol(s.selected);
duke@1:         return e == null || (e.kind != Kinds.PCK && e.kind != Kinds.TYP);
duke@1:     }
duke@1: 
duke@1:     /** If this tree is an identifier or a field, set its symbol, otherwise skip.
duke@1:      */
duke@1:     public static void setSymbol(JCTree tree, Symbol sym) {
duke@1:         tree = skipParens(tree);
duke@1:         switch (tree.getTag()) {
duke@1:         case JCTree.IDENT:
duke@1:             ((JCIdent) tree).sym = sym; break;
duke@1:         case JCTree.SELECT:
duke@1:             ((JCFieldAccess) tree).sym = sym; break;
duke@1:         default:
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** If this tree is a declaration or a block, return its flags field,
duke@1:      *  otherwise return 0.
duke@1:      */
duke@1:     public static long flags(JCTree tree) {
duke@1:         switch (tree.getTag()) {
duke@1:         case JCTree.VARDEF:
duke@1:             return ((JCVariableDecl) tree).mods.flags;
duke@1:         case JCTree.METHODDEF:
duke@1:             return ((JCMethodDecl) tree).mods.flags;
duke@1:         case JCTree.CLASSDEF:
duke@1:             return ((JCClassDecl) tree).mods.flags;
duke@1:         case JCTree.BLOCK:
duke@1:             return ((JCBlock) tree).flags;
duke@1:         default:
duke@1:             return 0;
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     /** Return first (smallest) flag in `flags':
duke@1:      *  pre: flags != 0
duke@1:      */
duke@1:     public static long firstFlag(long flags) {
duke@1:         int flag = 1;
duke@1:         while ((flag & StandardFlags) != 0 && (flag & flags) == 0)
duke@1:             flag = flag << 1;
duke@1:         return flag;
duke@1:     }
duke@1: 
duke@1:     /** Return flags as a string, separated by " ".
duke@1:      */
duke@1:     public static String flagNames(long flags) {
duke@1:         return Flags.toString(flags & StandardFlags).trim();
duke@1:     }
duke@1: 
duke@1:     /** Operator precedences values.
duke@1:      */
duke@1:     public static final int
duke@1:         notExpression = -1,   // not an expression
duke@1:         noPrec = 0,           // no enclosing expression
duke@1:         assignPrec = 1,
duke@1:         assignopPrec = 2,
duke@1:         condPrec = 3,
duke@1:         orPrec = 4,
duke@1:         andPrec = 5,
duke@1:         bitorPrec = 6,
duke@1:         bitxorPrec = 7,
duke@1:         bitandPrec = 8,
duke@1:         eqPrec = 9,
duke@1:         ordPrec = 10,
duke@1:         shiftPrec = 11,
duke@1:         addPrec = 12,
duke@1:         mulPrec = 13,
duke@1:         prefixPrec = 14,
duke@1:         postfixPrec = 15,
duke@1:         precCount = 16;
duke@1: 
duke@1: 
duke@1:     /** Map operators to their precedence levels.
duke@1:      */
duke@1:     public static int opPrec(int op) {
duke@1:         switch(op) {
duke@1:         case JCTree.POS:
duke@1:         case JCTree.NEG:
duke@1:         case JCTree.NOT:
duke@1:         case JCTree.COMPL:
duke@1:         case JCTree.PREINC:
duke@1:         case JCTree.PREDEC: return prefixPrec;
duke@1:         case JCTree.POSTINC:
duke@1:         case JCTree.POSTDEC:
duke@1:         case JCTree.NULLCHK: return postfixPrec;
duke@1:         case JCTree.ASSIGN: return assignPrec;
duke@1:         case JCTree.BITOR_ASG:
duke@1:         case JCTree.BITXOR_ASG:
duke@1:         case JCTree.BITAND_ASG:
duke@1:         case JCTree.SL_ASG:
duke@1:         case JCTree.SR_ASG:
duke@1:         case JCTree.USR_ASG:
duke@1:         case JCTree.PLUS_ASG:
duke@1:         case JCTree.MINUS_ASG:
duke@1:         case JCTree.MUL_ASG:
duke@1:         case JCTree.DIV_ASG:
duke@1:         case JCTree.MOD_ASG: return assignopPrec;
duke@1:         case JCTree.OR: return orPrec;
duke@1:         case JCTree.AND: return andPrec;
duke@1:         case JCTree.EQ:
duke@1:         case JCTree.NE: return eqPrec;
duke@1:         case JCTree.LT:
duke@1:         case JCTree.GT:
duke@1:         case JCTree.LE:
duke@1:         case JCTree.GE: return ordPrec;
duke@1:         case JCTree.BITOR: return bitorPrec;
duke@1:         case JCTree.BITXOR: return bitxorPrec;
duke@1:         case JCTree.BITAND: return bitandPrec;
duke@1:         case JCTree.SL:
duke@1:         case JCTree.SR:
duke@1:         case JCTree.USR: return shiftPrec;
duke@1:         case JCTree.PLUS:
duke@1:         case JCTree.MINUS: return addPrec;
duke@1:         case JCTree.MUL:
duke@1:         case JCTree.DIV:
duke@1:         case JCTree.MOD: return mulPrec;
duke@1:         case JCTree.TYPETEST: return ordPrec;
duke@1:         default: throw new AssertionError();
duke@1:         }
duke@1:     }
duke@1: 
duke@1:     static Tree.Kind tagToKind(int tag) {
duke@1:         switch (tag) {
duke@1:         // Postfix expressions
duke@1:         case JCTree.POSTINC:           // _ ++
duke@1:             return Tree.Kind.POSTFIX_INCREMENT;
duke@1:         case JCTree.POSTDEC:           // _ --
duke@1:             return Tree.Kind.POSTFIX_DECREMENT;
duke@1: 
duke@1:         // Unary operators
duke@1:         case JCTree.PREINC:            // ++ _
duke@1:             return Tree.Kind.PREFIX_INCREMENT;
duke@1:         case JCTree.PREDEC:            // -- _
duke@1:             return Tree.Kind.PREFIX_DECREMENT;
duke@1:         case JCTree.POS:               // +
duke@1:             return Tree.Kind.UNARY_PLUS;
duke@1:         case JCTree.NEG:               // -
duke@1:             return Tree.Kind.UNARY_MINUS;
duke@1:         case JCTree.COMPL:             // ~
duke@1:             return Tree.Kind.BITWISE_COMPLEMENT;
duke@1:         case JCTree.NOT:               // !
duke@1:             return Tree.Kind.LOGICAL_COMPLEMENT;
duke@1: 
duke@1:         // Binary operators
duke@1: 
duke@1:         // Multiplicative operators
duke@1:         case JCTree.MUL:               // *
duke@1:             return Tree.Kind.MULTIPLY;
duke@1:         case JCTree.DIV:               // /
duke@1:             return Tree.Kind.DIVIDE;
duke@1:         case JCTree.MOD:               // %
duke@1:             return Tree.Kind.REMAINDER;
duke@1: 
duke@1:         // Additive operators
duke@1:         case JCTree.PLUS:              // +
duke@1:             return Tree.Kind.PLUS;
duke@1:         case JCTree.MINUS:             // -
duke@1:             return Tree.Kind.MINUS;
duke@1: 
duke@1:         // Shift operators
duke@1:         case JCTree.SL:                // <<
duke@1:             return Tree.Kind.LEFT_SHIFT;
duke@1:         case JCTree.SR:                // >>
duke@1:             return Tree.Kind.RIGHT_SHIFT;
duke@1:         case JCTree.USR:               // >>>
duke@1:             return Tree.Kind.UNSIGNED_RIGHT_SHIFT;
duke@1: 
duke@1:         // Relational operators
duke@1:         case JCTree.LT:                // <
duke@1:             return Tree.Kind.LESS_THAN;
duke@1:         case JCTree.GT:                // >
duke@1:             return Tree.Kind.GREATER_THAN;
duke@1:         case JCTree.LE:                // <=
duke@1:             return Tree.Kind.LESS_THAN_EQUAL;
duke@1:         case JCTree.GE:                // >=
duke@1:             return Tree.Kind.GREATER_THAN_EQUAL;
duke@1: 
duke@1:         // Equality operators
duke@1:         case JCTree.EQ:                // ==
duke@1:             return Tree.Kind.EQUAL_TO;
duke@1:         case JCTree.NE:                // !=
duke@1:             return Tree.Kind.NOT_EQUAL_TO;
duke@1: 
duke@1:         // Bitwise and logical operators
duke@1:         case JCTree.BITAND:            // &
duke@1:             return Tree.Kind.AND;
duke@1:         case JCTree.BITXOR:            // ^
duke@1:             return Tree.Kind.XOR;
duke@1:         case JCTree.BITOR:             // |
duke@1:             return Tree.Kind.OR;
duke@1: 
duke@1:         // Conditional operators
duke@1:         case JCTree.AND:               // &&
duke@1:             return Tree.Kind.CONDITIONAL_AND;
duke@1:         case JCTree.OR:                // ||
duke@1:             return Tree.Kind.CONDITIONAL_OR;
duke@1: 
duke@1:         // Assignment operators
duke@1:         case JCTree.MUL_ASG:           // *=
duke@1:             return Tree.Kind.MULTIPLY_ASSIGNMENT;
duke@1:         case JCTree.DIV_ASG:           // /=
duke@1:             return Tree.Kind.DIVIDE_ASSIGNMENT;
duke@1:         case JCTree.MOD_ASG:           // %=
duke@1:             return Tree.Kind.REMAINDER_ASSIGNMENT;
duke@1:         case JCTree.PLUS_ASG:          // +=
duke@1:             return Tree.Kind.PLUS_ASSIGNMENT;
duke@1:         case JCTree.MINUS_ASG:         // -=
duke@1:             return Tree.Kind.MINUS_ASSIGNMENT;
duke@1:         case JCTree.SL_ASG:            // <<=
duke@1:             return Tree.Kind.LEFT_SHIFT_ASSIGNMENT;
duke@1:         case JCTree.SR_ASG:            // >>=
duke@1:             return Tree.Kind.RIGHT_SHIFT_ASSIGNMENT;
duke@1:         case JCTree.USR_ASG:           // >>>=
duke@1:             return Tree.Kind.UNSIGNED_RIGHT_SHIFT_ASSIGNMENT;
duke@1:         case JCTree.BITAND_ASG:        // &=
duke@1:             return Tree.Kind.AND_ASSIGNMENT;
duke@1:         case JCTree.BITXOR_ASG:        // ^=
duke@1:             return Tree.Kind.XOR_ASSIGNMENT;
duke@1:         case JCTree.BITOR_ASG:         // |=
duke@1:             return Tree.Kind.OR_ASSIGNMENT;
duke@1: 
duke@1:         // Null check (implementation detail), for example, __.getClass()
duke@1:         case JCTree.NULLCHK:
duke@1:             return Tree.Kind.OTHER;
duke@1: 
duke@1:         default:
duke@1:             return null;
duke@1:         }
duke@1:     }
jjg@308: 
jjg@308:     /**
jjg@308:      * Returns the underlying type of the tree if it is annotated type,
jjg@308:      * or the tree itself otherwise
jjg@308:      */
jjg@308:     public static JCExpression typeIn(JCExpression tree) {
jjg@308:         switch (tree.getTag()) {
jjg@308:         case JCTree.ANNOTATED_TYPE:
jjg@308:             return ((JCAnnotatedType)tree).underlyingType;
jjg@308:         case JCTree.IDENT: /* simple names */
jjg@308:         case JCTree.TYPEIDENT: /* primitive name */
jjg@308:         case JCTree.SELECT: /* qualified name */
jjg@308:         case JCTree.TYPEARRAY: /* array types */
jjg@308:         case JCTree.WILDCARD: /* wild cards */
jjg@308:         case JCTree.TYPEPARAMETER: /* type parameters */
jjg@308:         case JCTree.TYPEAPPLY: /* parameterized types */
jjg@308:             return tree;
jjg@308:         default:
jjg@308:             throw new AssertionError("Unexpected type tree: " + tree);
jjg@308:         }
jjg@308:     }
jjg@470: 
jjg@470:     public static JCTree innermostType(JCTree type) {
jjg@470:         switch (type.getTag()) {
jjg@470:         case JCTree.TYPEARRAY:
jjg@470:             return innermostType(((JCArrayTypeTree)type).elemtype);
jjg@470:         case JCTree.WILDCARD:
jjg@470:             return innermostType(((JCWildcard)type).inner);
jjg@470:         case JCTree.ANNOTATED_TYPE:
jjg@470:             return innermostType(((JCAnnotatedType)type).underlyingType);
jjg@470:         default:
jjg@470:             return type;
jjg@470:         }
jjg@470:     }
duke@1: }