langtools/src/share/classes/com/sun/tools/javac/tree/TreeInfo.java
changeset 10950 e87b50888909
parent 9300 c2de4dd9853b
child 11055 ec1418effa77
--- a/langtools/src/share/classes/com/sun/tools/javac/tree/TreeInfo.java	Sat Nov 05 00:02:33 2011 -0700
+++ b/langtools/src/share/classes/com/sun/tools/javac/tree/TreeInfo.java	Tue Nov 08 11:51:05 2011 -0800
@@ -35,6 +35,9 @@
 import com.sun.tools.javac.tree.JCTree.*;
 
 import static com.sun.tools.javac.code.Flags.*;
+import static com.sun.tools.javac.tree.JCTree.Tag.*;
+import static com.sun.tools.javac.tree.JCTree.Tag.BLOCK;
+import static com.sun.tools.javac.tree.JCTree.Tag.SYNCHRONIZED;
 
 /** Utility class containing inspector methods for trees.
  *
@@ -56,53 +59,60 @@
 
     /** The names of all operators.
      */
-    private Name[] opname = new Name[JCTree.MOD - JCTree.POS + 1];
+    private Name[] opname = new Name[Tag.getNumberOfOperators()];
+
+    private void setOpname(Tag tag, String name, Names names) {
+         setOpname(tag, names.fromString(name));
+     }
+     private void setOpname(Tag tag, Name name) {
+         opname[tag.operatorIndex()] = name;
+     }
 
     private TreeInfo(Context context) {
         context.put(treeInfoKey, this);
 
         Names names = Names.instance(context);
-        opname[JCTree.POS     - JCTree.POS] = names.fromString("+");
-        opname[JCTree.NEG     - JCTree.POS] = names.hyphen;
-        opname[JCTree.NOT     - JCTree.POS] = names.fromString("!");
-        opname[JCTree.COMPL   - JCTree.POS] = names.fromString("~");
-        opname[JCTree.PREINC  - JCTree.POS] = names.fromString("++");
-        opname[JCTree.PREDEC  - JCTree.POS] = names.fromString("--");
-        opname[JCTree.POSTINC - JCTree.POS] = names.fromString("++");
-        opname[JCTree.POSTDEC - JCTree.POS] = names.fromString("--");
-        opname[JCTree.NULLCHK - JCTree.POS] = names.fromString("<*nullchk*>");
-        opname[JCTree.OR      - JCTree.POS] = names.fromString("||");
-        opname[JCTree.AND     - JCTree.POS] = names.fromString("&&");
-        opname[JCTree.EQ      - JCTree.POS] = names.fromString("==");
-        opname[JCTree.NE      - JCTree.POS] = names.fromString("!=");
-        opname[JCTree.LT      - JCTree.POS] = names.fromString("<");
-        opname[JCTree.GT      - JCTree.POS] = names.fromString(">");
-        opname[JCTree.LE      - JCTree.POS] = names.fromString("<=");
-        opname[JCTree.GE      - JCTree.POS] = names.fromString(">=");
-        opname[JCTree.BITOR   - JCTree.POS] = names.fromString("|");
-        opname[JCTree.BITXOR  - JCTree.POS] = names.fromString("^");
-        opname[JCTree.BITAND  - JCTree.POS] = names.fromString("&");
-        opname[JCTree.SL      - JCTree.POS] = names.fromString("<<");
-        opname[JCTree.SR      - JCTree.POS] = names.fromString(">>");
-        opname[JCTree.USR     - JCTree.POS] = names.fromString(">>>");
-        opname[JCTree.PLUS    - JCTree.POS] = names.fromString("+");
-        opname[JCTree.MINUS   - JCTree.POS] = names.hyphen;
-        opname[JCTree.MUL     - JCTree.POS] = names.asterisk;
-        opname[JCTree.DIV     - JCTree.POS] = names.slash;
-        opname[JCTree.MOD     - JCTree.POS] = names.fromString("%");
+        setOpname(POS, "+", names);
+        setOpname(NEG, names.hyphen);
+        setOpname(NOT, "!", names);
+        setOpname(COMPL, "~", names);
+        setOpname(PREINC, "++", names);
+        setOpname(PREDEC, "--", names);
+        setOpname(POSTINC, "++", names);
+        setOpname(POSTDEC, "--", names);
+        setOpname(NULLCHK, "<*nullchk*>", names);
+        setOpname(OR, "||", names);
+        setOpname(AND, "&&", names);
+        setOpname(EQ, "==", names);
+        setOpname(NE, "!=", names);
+        setOpname(LT, "<", names);
+        setOpname(GT, ">", names);
+        setOpname(LE, "<=", names);
+        setOpname(GE, ">=", names);
+        setOpname(BITOR, "|", names);
+        setOpname(BITXOR, "^", names);
+        setOpname(BITAND, "&", names);
+        setOpname(SL, "<<", names);
+        setOpname(SR, ">>", names);
+        setOpname(USR, ">>>", names);
+        setOpname(PLUS, "+", names);
+        setOpname(MINUS, names.hyphen);
+        setOpname(MUL, names.asterisk);
+        setOpname(DIV, names.slash);
+        setOpname(MOD, "%", names);
     }
 
 
     /** Return name of operator with given tree tag.
      */
-    public Name operatorName(int tag) {
-        return opname[tag - JCTree.POS];
+    public Name operatorName(JCTree.Tag tag) {
+        return opname[tag.operatorIndex()];
     }
 
     /** Is tree a constructor declaration?
      */
     public static boolean isConstructor(JCTree tree) {
-        if (tree.getTag() == JCTree.METHODDEF) {
+        if (tree.hasTag(METHODDEF)) {
             Name name = ((JCMethodDecl) tree).name;
             return name == name.table.names.init;
         } else {
@@ -119,17 +129,17 @@
     }
 
     public static boolean isMultiCatch(JCCatch catchClause) {
-        return catchClause.param.vartype.getTag() == JCTree.TYPEUNION;
+        return catchClause.param.vartype.hasTag(TYPEUNION);
     }
 
     /** Is statement an initializer for a synthetic field?
      */
     public static boolean isSyntheticInit(JCTree stat) {
-        if (stat.getTag() == JCTree.EXEC) {
+        if (stat.hasTag(EXEC)) {
             JCExpressionStatement exec = (JCExpressionStatement)stat;
-            if (exec.expr.getTag() == JCTree.ASSIGN) {
+            if (exec.expr.hasTag(ASSIGN)) {
                 JCAssign assign = (JCAssign)exec.expr;
-                if (assign.lhs.getTag() == JCTree.SELECT) {
+                if (assign.lhs.hasTag(SELECT)) {
                     JCFieldAccess select = (JCFieldAccess)assign.lhs;
                     if (select.sym != null &&
                         (select.sym.flags() & SYNTHETIC) != 0) {
@@ -146,9 +156,9 @@
     /** If the expression is a method call, return the method name, null
      *  otherwise. */
     public static Name calledMethodName(JCTree tree) {
-        if (tree.getTag() == JCTree.EXEC) {
+        if (tree.hasTag(EXEC)) {
             JCExpressionStatement exec = (JCExpressionStatement)tree;
-            if (exec.expr.getTag() == JCTree.APPLY) {
+            if (exec.expr.hasTag(APPLY)) {
                 Name mname = TreeInfo.name(((JCMethodInvocation) exec.expr).meth);
                 return mname;
             }
@@ -192,7 +202,7 @@
 
     /** Return the first call in a constructor definition. */
     public static JCMethodInvocation firstConstructorCall(JCTree tree) {
-        if (tree.getTag() != JCTree.METHODDEF) return null;
+        if (!tree.hasTag(METHODDEF)) return null;
         JCMethodDecl md = (JCMethodDecl) tree;
         Names names = md.name.table.names;
         if (md.name != names.init) return null;
@@ -202,24 +212,24 @@
         while (stats.nonEmpty() && isSyntheticInit(stats.head))
             stats = stats.tail;
         if (stats.isEmpty()) return null;
-        if (stats.head.getTag() != JCTree.EXEC) return null;
+        if (!stats.head.hasTag(EXEC)) return null;
         JCExpressionStatement exec = (JCExpressionStatement) stats.head;
-        if (exec.expr.getTag() != JCTree.APPLY) return null;
+        if (!exec.expr.hasTag(APPLY)) return null;
         return (JCMethodInvocation)exec.expr;
     }
 
     /** Return true if a tree represents a diamond new expr. */
     public static boolean isDiamond(JCTree tree) {
         switch(tree.getTag()) {
-            case JCTree.TYPEAPPLY: return ((JCTypeApply)tree).getTypeArguments().isEmpty();
-            case JCTree.NEWCLASS: return isDiamond(((JCNewClass)tree).clazz);
+            case TYPEAPPLY: return ((JCTypeApply)tree).getTypeArguments().isEmpty();
+            case NEWCLASS: return isDiamond(((JCNewClass)tree).clazz);
             default: return false;
         }
     }
 
     /** Return true if a tree represents the null literal. */
     public static boolean isNull(JCTree tree) {
-        if (tree.getTag() != JCTree.LITERAL)
+        if (!tree.hasTag(LITERAL))
             return false;
         JCLiteral lit = (JCLiteral) tree;
         return (lit.typetag == TypeTags.BOT);
@@ -229,7 +239,7 @@
      *  the block itself if it is empty.
      */
     public static int firstStatPos(JCTree tree) {
-        if (tree.getTag() == JCTree.BLOCK && ((JCBlock) tree).stats.nonEmpty())
+        if (tree.hasTag(BLOCK) && ((JCBlock) tree).stats.nonEmpty())
             return ((JCBlock) tree).stats.head.pos;
         else
             return tree.pos;
@@ -239,11 +249,11 @@
      *  defined endpos.
      */
     public static int endPos(JCTree tree) {
-        if (tree.getTag() == JCTree.BLOCK && ((JCBlock) tree).endpos != Position.NOPOS)
+        if (tree.hasTag(BLOCK) && ((JCBlock) tree).endpos != Position.NOPOS)
             return ((JCBlock) tree).endpos;
-        else if (tree.getTag() == JCTree.SYNCHRONIZED)
+        else if (tree.hasTag(SYNCHRONIZED))
             return endPos(((JCSynchronized) tree).body);
-        else if (tree.getTag() == JCTree.TRY) {
+        else if (tree.hasTag(TRY)) {
             JCTry t = (JCTry) tree;
             return endPos((t.finalizer != null)
                           ? t.finalizer
@@ -263,73 +273,73 @@
             return Position.NOPOS;
 
         switch(tree.getTag()) {
-        case(JCTree.APPLY):
-            return getStartPos(((JCMethodInvocation) tree).meth);
-        case(JCTree.ASSIGN):
-            return getStartPos(((JCAssign) tree).lhs);
-        case(JCTree.BITOR_ASG): case(JCTree.BITXOR_ASG): case(JCTree.BITAND_ASG):
-        case(JCTree.SL_ASG): case(JCTree.SR_ASG): case(JCTree.USR_ASG):
-        case(JCTree.PLUS_ASG): case(JCTree.MINUS_ASG): case(JCTree.MUL_ASG):
-        case(JCTree.DIV_ASG): case(JCTree.MOD_ASG):
-            return getStartPos(((JCAssignOp) tree).lhs);
-        case(JCTree.OR): case(JCTree.AND): case(JCTree.BITOR):
-        case(JCTree.BITXOR): case(JCTree.BITAND): case(JCTree.EQ):
-        case(JCTree.NE): case(JCTree.LT): case(JCTree.GT):
-        case(JCTree.LE): case(JCTree.GE): case(JCTree.SL):
-        case(JCTree.SR): case(JCTree.USR): case(JCTree.PLUS):
-        case(JCTree.MINUS): case(JCTree.MUL): case(JCTree.DIV):
-        case(JCTree.MOD):
-            return getStartPos(((JCBinary) tree).lhs);
-        case(JCTree.CLASSDEF): {
-            JCClassDecl node = (JCClassDecl)tree;
-            if (node.mods.pos != Position.NOPOS)
-                return node.mods.pos;
-            break;
-        }
-        case(JCTree.CONDEXPR):
-            return getStartPos(((JCConditional) tree).cond);
-        case(JCTree.EXEC):
-            return getStartPos(((JCExpressionStatement) tree).expr);
-        case(JCTree.INDEXED):
-            return getStartPos(((JCArrayAccess) tree).indexed);
-        case(JCTree.METHODDEF): {
-            JCMethodDecl node = (JCMethodDecl)tree;
-            if (node.mods.pos != Position.NOPOS)
-                return node.mods.pos;
-            if (node.typarams.nonEmpty()) // List.nil() used for no typarams
-                return getStartPos(node.typarams.head);
-            return node.restype == null ? node.pos : getStartPos(node.restype);
-        }
-        case(JCTree.SELECT):
-            return getStartPos(((JCFieldAccess) tree).selected);
-        case(JCTree.TYPEAPPLY):
-            return getStartPos(((JCTypeApply) tree).clazz);
-        case(JCTree.TYPEARRAY):
-            return getStartPos(((JCArrayTypeTree) tree).elemtype);
-        case(JCTree.TYPETEST):
-            return getStartPos(((JCInstanceOf) tree).expr);
-        case(JCTree.POSTINC):
-        case(JCTree.POSTDEC):
-            return getStartPos(((JCUnary) tree).arg);
-        case(JCTree.NEWCLASS): {
-            JCNewClass node = (JCNewClass)tree;
-            if (node.encl != null)
-                return getStartPos(node.encl);
-            break;
-        }
-        case(JCTree.VARDEF): {
-            JCVariableDecl node = (JCVariableDecl)tree;
-            if (node.mods.pos != Position.NOPOS) {
-                return node.mods.pos;
-            } else {
-                return getStartPos(node.vartype);
+            case APPLY:
+                return getStartPos(((JCMethodInvocation) tree).meth);
+            case ASSIGN:
+                return getStartPos(((JCAssign) tree).lhs);
+            case BITOR_ASG: case BITXOR_ASG: case BITAND_ASG:
+            case SL_ASG: case SR_ASG: case USR_ASG:
+            case PLUS_ASG: case MINUS_ASG: case MUL_ASG:
+            case DIV_ASG: case MOD_ASG:
+                return getStartPos(((JCAssignOp) tree).lhs);
+            case OR: case AND: case BITOR:
+            case BITXOR: case BITAND: case EQ:
+            case NE: case LT: case GT:
+            case LE: case GE: case SL:
+            case SR: case USR: case PLUS:
+            case MINUS: case MUL: case DIV:
+            case MOD:
+                return getStartPos(((JCBinary) tree).lhs);
+            case CLASSDEF: {
+                JCClassDecl node = (JCClassDecl)tree;
+                if (node.mods.pos != Position.NOPOS)
+                    return node.mods.pos;
+                break;
             }
-        }
-        case(JCTree.ERRONEOUS): {
-            JCErroneous node = (JCErroneous)tree;
-            if (node.errs != null && node.errs.nonEmpty())
-                return getStartPos(node.errs.head);
-        }
+            case CONDEXPR:
+                return getStartPos(((JCConditional) tree).cond);
+            case EXEC:
+                return getStartPos(((JCExpressionStatement) tree).expr);
+            case INDEXED:
+                return getStartPos(((JCArrayAccess) tree).indexed);
+            case METHODDEF: {
+                JCMethodDecl node = (JCMethodDecl)tree;
+                if (node.mods.pos != Position.NOPOS)
+                    return node.mods.pos;
+                if (node.typarams.nonEmpty()) // List.nil() used for no typarams
+                    return getStartPos(node.typarams.head);
+                return node.restype == null ? node.pos : getStartPos(node.restype);
+            }
+            case SELECT:
+                return getStartPos(((JCFieldAccess) tree).selected);
+            case TYPEAPPLY:
+                return getStartPos(((JCTypeApply) tree).clazz);
+            case TYPEARRAY:
+                return getStartPos(((JCArrayTypeTree) tree).elemtype);
+            case TYPETEST:
+                return getStartPos(((JCInstanceOf) tree).expr);
+            case POSTINC:
+            case POSTDEC:
+                return getStartPos(((JCUnary) tree).arg);
+            case NEWCLASS: {
+                JCNewClass node = (JCNewClass)tree;
+                if (node.encl != null)
+                    return getStartPos(node.encl);
+                break;
+            }
+            case VARDEF: {
+                JCVariableDecl node = (JCVariableDecl)tree;
+                if (node.mods.pos != Position.NOPOS) {
+                    return node.mods.pos;
+                } else {
+                    return getStartPos(node.vartype);
+                }
+            }
+            case ERRONEOUS: {
+                JCErroneous node = (JCErroneous)tree;
+                if (node.errs != null && node.errs.nonEmpty())
+                    return getStartPos(node.errs.head);
+            }
         }
         return tree.pos;
     }
@@ -350,75 +360,75 @@
             return mapPos;
 
         switch(tree.getTag()) {
-        case(JCTree.BITOR_ASG): case(JCTree.BITXOR_ASG): case(JCTree.BITAND_ASG):
-        case(JCTree.SL_ASG): case(JCTree.SR_ASG): case(JCTree.USR_ASG):
-        case(JCTree.PLUS_ASG): case(JCTree.MINUS_ASG): case(JCTree.MUL_ASG):
-        case(JCTree.DIV_ASG): case(JCTree.MOD_ASG):
-            return getEndPos(((JCAssignOp) tree).rhs, endPositions);
-        case(JCTree.OR): case(JCTree.AND): case(JCTree.BITOR):
-        case(JCTree.BITXOR): case(JCTree.BITAND): case(JCTree.EQ):
-        case(JCTree.NE): case(JCTree.LT): case(JCTree.GT):
-        case(JCTree.LE): case(JCTree.GE): case(JCTree.SL):
-        case(JCTree.SR): case(JCTree.USR): case(JCTree.PLUS):
-        case(JCTree.MINUS): case(JCTree.MUL): case(JCTree.DIV):
-        case(JCTree.MOD):
-            return getEndPos(((JCBinary) tree).rhs, endPositions);
-        case(JCTree.CASE):
-            return getEndPos(((JCCase) tree).stats.last(), endPositions);
-        case(JCTree.CATCH):
-            return getEndPos(((JCCatch) tree).body, endPositions);
-        case(JCTree.CONDEXPR):
-            return getEndPos(((JCConditional) tree).falsepart, endPositions);
-        case(JCTree.FORLOOP):
-            return getEndPos(((JCForLoop) tree).body, endPositions);
-        case(JCTree.FOREACHLOOP):
-            return getEndPos(((JCEnhancedForLoop) tree).body, endPositions);
-        case(JCTree.IF): {
-            JCIf node = (JCIf)tree;
-            if (node.elsepart == null) {
-                return getEndPos(node.thenpart, endPositions);
-            } else {
-                return getEndPos(node.elsepart, endPositions);
+            case BITOR_ASG: case BITXOR_ASG: case BITAND_ASG:
+            case SL_ASG: case SR_ASG: case USR_ASG:
+            case PLUS_ASG: case MINUS_ASG: case MUL_ASG:
+            case DIV_ASG: case MOD_ASG:
+                return getEndPos(((JCAssignOp) tree).rhs, endPositions);
+            case OR: case AND: case BITOR:
+            case BITXOR: case BITAND: case EQ:
+            case NE: case LT: case GT:
+            case LE: case GE: case SL:
+            case SR: case USR: case PLUS:
+            case MINUS: case MUL: case DIV:
+            case MOD:
+                return getEndPos(((JCBinary) tree).rhs, endPositions);
+            case CASE:
+                return getEndPos(((JCCase) tree).stats.last(), endPositions);
+            case CATCH:
+                return getEndPos(((JCCatch) tree).body, endPositions);
+            case CONDEXPR:
+                return getEndPos(((JCConditional) tree).falsepart, endPositions);
+            case FORLOOP:
+                return getEndPos(((JCForLoop) tree).body, endPositions);
+            case FOREACHLOOP:
+                return getEndPos(((JCEnhancedForLoop) tree).body, endPositions);
+            case IF: {
+                JCIf node = (JCIf)tree;
+                if (node.elsepart == null) {
+                    return getEndPos(node.thenpart, endPositions);
+                } else {
+                    return getEndPos(node.elsepart, endPositions);
+                }
             }
-        }
-        case(JCTree.LABELLED):
-            return getEndPos(((JCLabeledStatement) tree).body, endPositions);
-        case(JCTree.MODIFIERS):
-            return getEndPos(((JCModifiers) tree).annotations.last(), endPositions);
-        case(JCTree.SYNCHRONIZED):
-            return getEndPos(((JCSynchronized) tree).body, endPositions);
-        case(JCTree.TOPLEVEL):
-            return getEndPos(((JCCompilationUnit) tree).defs.last(), endPositions);
-        case(JCTree.TRY): {
-            JCTry node = (JCTry)tree;
-            if (node.finalizer != null) {
-                return getEndPos(node.finalizer, endPositions);
-            } else if (!node.catchers.isEmpty()) {
-                return getEndPos(node.catchers.last(), endPositions);
-            } else {
-                return getEndPos(node.body, endPositions);
+            case LABELLED:
+                return getEndPos(((JCLabeledStatement) tree).body, endPositions);
+            case MODIFIERS:
+                return getEndPos(((JCModifiers) tree).annotations.last(), endPositions);
+            case SYNCHRONIZED:
+                return getEndPos(((JCSynchronized) tree).body, endPositions);
+            case TOPLEVEL:
+                return getEndPos(((JCCompilationUnit) tree).defs.last(), endPositions);
+            case TRY: {
+                JCTry node = (JCTry)tree;
+                if (node.finalizer != null) {
+                    return getEndPos(node.finalizer, endPositions);
+                } else if (!node.catchers.isEmpty()) {
+                    return getEndPos(node.catchers.last(), endPositions);
+                } else {
+                    return getEndPos(node.body, endPositions);
+                }
             }
-        }
-        case(JCTree.WILDCARD):
-            return getEndPos(((JCWildcard) tree).inner, endPositions);
-        case(JCTree.TYPECAST):
-            return getEndPos(((JCTypeCast) tree).expr, endPositions);
-        case(JCTree.TYPETEST):
-            return getEndPos(((JCInstanceOf) tree).clazz, endPositions);
-        case(JCTree.POS):
-        case(JCTree.NEG):
-        case(JCTree.NOT):
-        case(JCTree.COMPL):
-        case(JCTree.PREINC):
-        case(JCTree.PREDEC):
-            return getEndPos(((JCUnary) tree).arg, endPositions);
-        case(JCTree.WHILELOOP):
-            return getEndPos(((JCWhileLoop) tree).body, endPositions);
-        case(JCTree.ERRONEOUS): {
-            JCErroneous node = (JCErroneous)tree;
-            if (node.errs != null && node.errs.nonEmpty())
-                return getEndPos(node.errs.last(), endPositions);
-        }
+            case WILDCARD:
+                return getEndPos(((JCWildcard) tree).inner, endPositions);
+            case TYPECAST:
+                return getEndPos(((JCTypeCast) tree).expr, endPositions);
+            case TYPETEST:
+                return getEndPos(((JCInstanceOf) tree).clazz, endPositions);
+            case POS:
+            case NEG:
+            case NOT:
+            case COMPL:
+            case PREINC:
+            case PREDEC:
+                return getEndPos(((JCUnary) tree).arg, endPositions);
+            case WHILELOOP:
+                return getEndPos(((JCWhileLoop) tree).body, endPositions);
+            case ERRONEOUS: {
+                JCErroneous node = (JCErroneous)tree;
+                if (node.errs != null && node.errs.nonEmpty())
+                    return getEndPos(node.errs.last(), endPositions);
+            }
         }
         return Position.NOPOS;
     }
@@ -443,11 +453,11 @@
     /** The position of the finalizer of given try/synchronized statement.
      */
     public static int finalizerPos(JCTree tree) {
-        if (tree.getTag() == JCTree.TRY) {
+        if (tree.hasTag(TRY)) {
             JCTry t = (JCTry) tree;
             Assert.checkNonNull(t.finalizer);
             return firstStatPos(t.finalizer);
-        } else if (tree.getTag() == JCTree.SYNCHRONIZED) {
+        } else if (tree.hasTag(SYNCHRONIZED)) {
             return endPos(((JCSynchronized) tree).body);
         } else {
             throw new AssertionError();
@@ -547,9 +557,9 @@
     public static JCTree referencedStatement(JCLabeledStatement tree) {
         JCTree t = tree;
         do t = ((JCLabeledStatement) t).body;
-        while (t.getTag() == JCTree.LABELLED);
+        while (t.hasTag(LABELLED));
         switch (t.getTag()) {
-        case JCTree.DOLOOP: case JCTree.WHILELOOP: case JCTree.FORLOOP: case JCTree.FOREACHLOOP: case JCTree.SWITCH:
+        case DOLOOP: case WHILELOOP: case FORLOOP: case FOREACHLOOP: case SWITCH:
             return t;
         default:
             return tree;
@@ -559,7 +569,7 @@
     /** Skip parens and return the enclosed expression
      */
     public static JCExpression skipParens(JCExpression tree) {
-        while (tree.getTag() == JCTree.PARENS) {
+        while (tree.hasTag(PARENS)) {
             tree = ((JCParens) tree).expr;
         }
         return tree;
@@ -568,7 +578,7 @@
     /** Skip parens and return the enclosed expression
      */
     public static JCTree skipParens(JCTree tree) {
-        if (tree.getTag() == JCTree.PARENS)
+        if (tree.hasTag(PARENS))
             return skipParens((JCParens)tree);
         else
             return tree;
@@ -588,11 +598,11 @@
      */
     public static Name name(JCTree tree) {
         switch (tree.getTag()) {
-        case JCTree.IDENT:
+        case IDENT:
             return ((JCIdent) tree).name;
-        case JCTree.SELECT:
+        case SELECT:
             return ((JCFieldAccess) tree).name;
-        case JCTree.TYPEAPPLY:
+        case TYPEAPPLY:
             return name(((JCTypeApply) tree).clazz);
         default:
             return null;
@@ -605,9 +615,9 @@
     public static Name fullName(JCTree tree) {
         tree = skipParens(tree);
         switch (tree.getTag()) {
-        case JCTree.IDENT:
+        case IDENT:
             return ((JCIdent) tree).name;
-        case JCTree.SELECT:
+        case SELECT:
             Name sname = fullName(((JCFieldAccess) tree).selected);
             return sname == null ? null : sname.append('.', name(tree));
         default:
@@ -618,11 +628,11 @@
     public static Symbol symbolFor(JCTree node) {
         node = skipParens(node);
         switch (node.getTag()) {
-        case JCTree.CLASSDEF:
+        case CLASSDEF:
             return ((JCClassDecl) node).sym;
-        case JCTree.METHODDEF:
+        case METHODDEF:
             return ((JCMethodDecl) node).sym;
-        case JCTree.VARDEF:
+        case VARDEF:
             return ((JCVariableDecl) node).sym;
         default:
             return null;
@@ -632,9 +642,9 @@
     public static boolean isDeclaration(JCTree node) {
         node = skipParens(node);
         switch (node.getTag()) {
-        case JCTree.CLASSDEF:
-        case JCTree.METHODDEF:
-        case JCTree.VARDEF:
+        case CLASSDEF:
+        case METHODDEF:
+        case VARDEF:
             return true;
         default:
             return false;
@@ -647,11 +657,11 @@
     public static Symbol symbol(JCTree tree) {
         tree = skipParens(tree);
         switch (tree.getTag()) {
-        case JCTree.IDENT:
+        case IDENT:
             return ((JCIdent) tree).sym;
-        case JCTree.SELECT:
+        case SELECT:
             return ((JCFieldAccess) tree).sym;
-        case JCTree.TYPEAPPLY:
+        case TYPEAPPLY:
             return symbol(((JCTypeApply) tree).clazz);
         default:
             return null;
@@ -661,7 +671,7 @@
     /** Return true if this is a nonstatic selection. */
     public static boolean nonstaticSelect(JCTree tree) {
         tree = skipParens(tree);
-        if (tree.getTag() != JCTree.SELECT) return false;
+        if (!tree.hasTag(SELECT)) return false;
         JCFieldAccess s = (JCFieldAccess) tree;
         Symbol e = symbol(s.selected);
         return e == null || (e.kind != Kinds.PCK && e.kind != Kinds.TYP);
@@ -672,9 +682,9 @@
     public static void setSymbol(JCTree tree, Symbol sym) {
         tree = skipParens(tree);
         switch (tree.getTag()) {
-        case JCTree.IDENT:
+        case IDENT:
             ((JCIdent) tree).sym = sym; break;
-        case JCTree.SELECT:
+        case SELECT:
             ((JCFieldAccess) tree).sym = sym; break;
         default:
         }
@@ -685,13 +695,13 @@
      */
     public static long flags(JCTree tree) {
         switch (tree.getTag()) {
-        case JCTree.VARDEF:
+        case VARDEF:
             return ((JCVariableDecl) tree).mods.flags;
-        case JCTree.METHODDEF:
+        case METHODDEF:
             return ((JCMethodDecl) tree).mods.flags;
-        case JCTree.CLASSDEF:
+        case CLASSDEF:
             return ((JCClassDecl) tree).mods.flags;
-        case JCTree.BLOCK:
+        case BLOCK:
             return ((JCBlock) tree).flags;
         default:
             return 0;
@@ -739,155 +749,155 @@
 
     /** Map operators to their precedence levels.
      */
-    public static int opPrec(int op) {
+    public static int opPrec(JCTree.Tag op) {
         switch(op) {
-        case JCTree.POS:
-        case JCTree.NEG:
-        case JCTree.NOT:
-        case JCTree.COMPL:
-        case JCTree.PREINC:
-        case JCTree.PREDEC: return prefixPrec;
-        case JCTree.POSTINC:
-        case JCTree.POSTDEC:
-        case JCTree.NULLCHK: return postfixPrec;
-        case JCTree.ASSIGN: return assignPrec;
-        case JCTree.BITOR_ASG:
-        case JCTree.BITXOR_ASG:
-        case JCTree.BITAND_ASG:
-        case JCTree.SL_ASG:
-        case JCTree.SR_ASG:
-        case JCTree.USR_ASG:
-        case JCTree.PLUS_ASG:
-        case JCTree.MINUS_ASG:
-        case JCTree.MUL_ASG:
-        case JCTree.DIV_ASG:
-        case JCTree.MOD_ASG: return assignopPrec;
-        case JCTree.OR: return orPrec;
-        case JCTree.AND: return andPrec;
-        case JCTree.EQ:
-        case JCTree.NE: return eqPrec;
-        case JCTree.LT:
-        case JCTree.GT:
-        case JCTree.LE:
-        case JCTree.GE: return ordPrec;
-        case JCTree.BITOR: return bitorPrec;
-        case JCTree.BITXOR: return bitxorPrec;
-        case JCTree.BITAND: return bitandPrec;
-        case JCTree.SL:
-        case JCTree.SR:
-        case JCTree.USR: return shiftPrec;
-        case JCTree.PLUS:
-        case JCTree.MINUS: return addPrec;
-        case JCTree.MUL:
-        case JCTree.DIV:
-        case JCTree.MOD: return mulPrec;
-        case JCTree.TYPETEST: return ordPrec;
+        case POS:
+        case NEG:
+        case NOT:
+        case COMPL:
+        case PREINC:
+        case PREDEC: return prefixPrec;
+        case POSTINC:
+        case POSTDEC:
+        case NULLCHK: return postfixPrec;
+        case ASSIGN: return assignPrec;
+        case BITOR_ASG:
+        case BITXOR_ASG:
+        case BITAND_ASG:
+        case SL_ASG:
+        case SR_ASG:
+        case USR_ASG:
+        case PLUS_ASG:
+        case MINUS_ASG:
+        case MUL_ASG:
+        case DIV_ASG:
+        case MOD_ASG: return assignopPrec;
+        case OR: return orPrec;
+        case AND: return andPrec;
+        case EQ:
+        case NE: return eqPrec;
+        case LT:
+        case GT:
+        case LE:
+        case GE: return ordPrec;
+        case BITOR: return bitorPrec;
+        case BITXOR: return bitxorPrec;
+        case BITAND: return bitandPrec;
+        case SL:
+        case SR:
+        case USR: return shiftPrec;
+        case PLUS:
+        case MINUS: return addPrec;
+        case MUL:
+        case DIV:
+        case MOD: return mulPrec;
+        case TYPETEST: return ordPrec;
         default: throw new AssertionError();
         }
     }
 
-    static Tree.Kind tagToKind(int tag) {
+    static Tree.Kind tagToKind(JCTree.Tag tag) {
         switch (tag) {
         // Postfix expressions
-        case JCTree.POSTINC:           // _ ++
+        case POSTINC:           // _ ++
             return Tree.Kind.POSTFIX_INCREMENT;
-        case JCTree.POSTDEC:           // _ --
+        case POSTDEC:           // _ --
             return Tree.Kind.POSTFIX_DECREMENT;
 
         // Unary operators
-        case JCTree.PREINC:            // ++ _
+        case PREINC:            // ++ _
             return Tree.Kind.PREFIX_INCREMENT;
-        case JCTree.PREDEC:            // -- _
+        case PREDEC:            // -- _
             return Tree.Kind.PREFIX_DECREMENT;
-        case JCTree.POS:               // +
+        case POS:               // +
             return Tree.Kind.UNARY_PLUS;
-        case JCTree.NEG:               // -
+        case NEG:               // -
             return Tree.Kind.UNARY_MINUS;
-        case JCTree.COMPL:             // ~
+        case COMPL:             // ~
             return Tree.Kind.BITWISE_COMPLEMENT;
-        case JCTree.NOT:               // !
+        case NOT:               // !
             return Tree.Kind.LOGICAL_COMPLEMENT;
 
         // Binary operators
 
         // Multiplicative operators
-        case JCTree.MUL:               // *
+        case MUL:               // *
             return Tree.Kind.MULTIPLY;
-        case JCTree.DIV:               // /
+        case DIV:               // /
             return Tree.Kind.DIVIDE;
-        case JCTree.MOD:               // %
+        case MOD:               // %
             return Tree.Kind.REMAINDER;
 
         // Additive operators
-        case JCTree.PLUS:              // +
+        case PLUS:              // +
             return Tree.Kind.PLUS;
-        case JCTree.MINUS:             // -
+        case MINUS:             // -
             return Tree.Kind.MINUS;
 
         // Shift operators
-        case JCTree.SL:                // <<
+        case SL:                // <<
             return Tree.Kind.LEFT_SHIFT;
-        case JCTree.SR:                // >>
+        case SR:                // >>
             return Tree.Kind.RIGHT_SHIFT;
-        case JCTree.USR:               // >>>
+        case USR:               // >>>
             return Tree.Kind.UNSIGNED_RIGHT_SHIFT;
 
         // Relational operators
-        case JCTree.LT:                // <
+        case LT:                // <
             return Tree.Kind.LESS_THAN;
-        case JCTree.GT:                // >
+        case GT:                // >
             return Tree.Kind.GREATER_THAN;
-        case JCTree.LE:                // <=
+        case LE:                // <=
             return Tree.Kind.LESS_THAN_EQUAL;
-        case JCTree.GE:                // >=
+        case GE:                // >=
             return Tree.Kind.GREATER_THAN_EQUAL;
 
         // Equality operators
-        case JCTree.EQ:                // ==
+        case EQ:                // ==
             return Tree.Kind.EQUAL_TO;
-        case JCTree.NE:                // !=
+        case NE:                // !=
             return Tree.Kind.NOT_EQUAL_TO;
 
         // Bitwise and logical operators
-        case JCTree.BITAND:            // &
+        case BITAND:            // &
             return Tree.Kind.AND;
-        case JCTree.BITXOR:            // ^
+        case BITXOR:            // ^
             return Tree.Kind.XOR;
-        case JCTree.BITOR:             // |
+        case BITOR:             // |
             return Tree.Kind.OR;
 
         // Conditional operators
-        case JCTree.AND:               // &&
+        case AND:               // &&
             return Tree.Kind.CONDITIONAL_AND;
-        case JCTree.OR:                // ||
+        case OR:                // ||
             return Tree.Kind.CONDITIONAL_OR;
 
         // Assignment operators
-        case JCTree.MUL_ASG:           // *=
+        case MUL_ASG:           // *=
             return Tree.Kind.MULTIPLY_ASSIGNMENT;
-        case JCTree.DIV_ASG:           // /=
+        case DIV_ASG:           // /=
             return Tree.Kind.DIVIDE_ASSIGNMENT;
-        case JCTree.MOD_ASG:           // %=
+        case MOD_ASG:           // %=
             return Tree.Kind.REMAINDER_ASSIGNMENT;
-        case JCTree.PLUS_ASG:          // +=
+        case PLUS_ASG:          // +=
             return Tree.Kind.PLUS_ASSIGNMENT;
-        case JCTree.MINUS_ASG:         // -=
+        case MINUS_ASG:         // -=
             return Tree.Kind.MINUS_ASSIGNMENT;
-        case JCTree.SL_ASG:            // <<=
+        case SL_ASG:            // <<=
             return Tree.Kind.LEFT_SHIFT_ASSIGNMENT;
-        case JCTree.SR_ASG:            // >>=
+        case SR_ASG:            // >>=
             return Tree.Kind.RIGHT_SHIFT_ASSIGNMENT;
-        case JCTree.USR_ASG:           // >>>=
+        case USR_ASG:           // >>>=
             return Tree.Kind.UNSIGNED_RIGHT_SHIFT_ASSIGNMENT;
-        case JCTree.BITAND_ASG:        // &=
+        case BITAND_ASG:        // &=
             return Tree.Kind.AND_ASSIGNMENT;
-        case JCTree.BITXOR_ASG:        // ^=
+        case BITXOR_ASG:        // ^=
             return Tree.Kind.XOR_ASSIGNMENT;
-        case JCTree.BITOR_ASG:         // |=
+        case BITOR_ASG:         // |=
             return Tree.Kind.OR_ASSIGNMENT;
 
         // Null check (implementation detail), for example, __.getClass()
-        case JCTree.NULLCHK:
+        case NULLCHK:
             return Tree.Kind.OTHER;
 
         default:
@@ -901,13 +911,13 @@
      */
     public static JCExpression typeIn(JCExpression tree) {
         switch (tree.getTag()) {
-        case JCTree.IDENT: /* simple names */
-        case JCTree.TYPEIDENT: /* primitive name */
-        case JCTree.SELECT: /* qualified name */
-        case JCTree.TYPEARRAY: /* array types */
-        case JCTree.WILDCARD: /* wild cards */
-        case JCTree.TYPEPARAMETER: /* type parameters */
-        case JCTree.TYPEAPPLY: /* parameterized types */
+        case IDENT: /* simple names */
+        case TYPEIDENT: /* primitive name */
+        case SELECT: /* qualified name */
+        case TYPEARRAY: /* array types */
+        case WILDCARD: /* wild cards */
+        case TYPEPARAMETER: /* type parameters */
+        case TYPEAPPLY: /* parameterized types */
             return tree;
         default:
             throw new AssertionError("Unexpected type tree: " + tree);
@@ -916,9 +926,9 @@
 
     public static JCTree innermostType(JCTree type) {
         switch (type.getTag()) {
-        case JCTree.TYPEARRAY:
+        case TYPEARRAY:
             return innermostType(((JCArrayTypeTree)type).elemtype);
-        case JCTree.WILDCARD:
+        case WILDCARD:
             return innermostType(((JCWildcard)type).inner);
         default:
             return type;