langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/api/JavacTrees.java
changeset 25874 83c19f00452c
parent 25443 9187d77f2c64
child 26264 a09fedde76be
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/api/JavacTrees.java	Sun Aug 17 15:52:32 2014 +0100
@@ -0,0 +1,941 @@
+/*
+ * Copyright (c) 2005, 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package com.sun.tools.javac.api;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.lang.model.element.AnnotationMirror;
+import javax.lang.model.element.AnnotationValue;
+import javax.lang.model.element.Element;
+import javax.lang.model.element.ElementKind;
+import javax.lang.model.element.ExecutableElement;
+import javax.lang.model.element.TypeElement;
+import javax.lang.model.type.DeclaredType;
+import javax.lang.model.type.TypeKind;
+import javax.lang.model.type.TypeMirror;
+import javax.tools.Diagnostic;
+import javax.tools.JavaCompiler;
+import javax.tools.JavaFileObject;
+
+import com.sun.source.doctree.DocCommentTree;
+import com.sun.source.doctree.DocTree;
+import com.sun.source.tree.CatchTree;
+import com.sun.source.tree.CompilationUnitTree;
+import com.sun.source.tree.Scope;
+import com.sun.source.tree.Tree;
+import com.sun.source.util.DocSourcePositions;
+import com.sun.source.util.DocTreePath;
+import com.sun.source.util.DocTreeScanner;
+import com.sun.source.util.DocTrees;
+import com.sun.source.util.JavacTask;
+import com.sun.source.util.TreePath;
+import com.sun.tools.javac.code.Flags;
+import com.sun.tools.javac.code.Kinds;
+import com.sun.tools.javac.code.Symbol;
+import com.sun.tools.javac.code.Symbol.ClassSymbol;
+import com.sun.tools.javac.code.Symbol.MethodSymbol;
+import com.sun.tools.javac.code.Symbol.PackageSymbol;
+import com.sun.tools.javac.code.Symbol.TypeSymbol;
+import com.sun.tools.javac.code.Symbol.VarSymbol;
+import com.sun.tools.javac.code.Type;
+import com.sun.tools.javac.code.Type.ArrayType;
+import com.sun.tools.javac.code.Type.ClassType;
+import com.sun.tools.javac.code.Type.ErrorType;
+import com.sun.tools.javac.code.Type.UnionClassType;
+import com.sun.tools.javac.code.Types;
+import com.sun.tools.javac.code.Types.TypeRelation;
+import com.sun.tools.javac.comp.Attr;
+import com.sun.tools.javac.comp.AttrContext;
+import com.sun.tools.javac.comp.Enter;
+import com.sun.tools.javac.comp.Env;
+import com.sun.tools.javac.comp.MemberEnter;
+import com.sun.tools.javac.comp.Resolve;
+import com.sun.tools.javac.model.JavacElements;
+import com.sun.tools.javac.processing.JavacProcessingEnvironment;
+import com.sun.tools.javac.tree.DCTree;
+import com.sun.tools.javac.tree.DCTree.DCBlockTag;
+import com.sun.tools.javac.tree.DCTree.DCDocComment;
+import com.sun.tools.javac.tree.DCTree.DCEndPosTree;
+import com.sun.tools.javac.tree.DCTree.DCErroneous;
+import com.sun.tools.javac.tree.DCTree.DCIdentifier;
+import com.sun.tools.javac.tree.DCTree.DCParam;
+import com.sun.tools.javac.tree.DCTree.DCReference;
+import com.sun.tools.javac.tree.DCTree.DCText;
+import com.sun.tools.javac.tree.EndPosTable;
+import com.sun.tools.javac.tree.JCTree;
+import com.sun.tools.javac.tree.JCTree.*;
+import com.sun.tools.javac.tree.TreeCopier;
+import com.sun.tools.javac.tree.TreeInfo;
+import com.sun.tools.javac.tree.TreeMaker;
+import com.sun.tools.javac.util.Abort;
+import com.sun.tools.javac.util.Assert;
+import com.sun.tools.javac.util.Context;
+import com.sun.tools.javac.util.JCDiagnostic;
+import com.sun.tools.javac.util.List;
+import com.sun.tools.javac.util.ListBuffer;
+import com.sun.tools.javac.util.Log;
+import com.sun.tools.javac.util.Name;
+import com.sun.tools.javac.util.Names;
+import com.sun.tools.javac.util.Pair;
+import com.sun.tools.javac.util.Position;
+import static com.sun.tools.javac.code.TypeTag.*;
+
+/**
+ * Provides an implementation of Trees.
+ *
+ * <p><b>This is NOT part of any supported API.
+ * If you write code that depends on this, you do so at your own
+ * risk.  This code and its internal interfaces are subject to change
+ * or deletion without notice.</b></p>
+ *
+ * @author Peter von der Ah&eacute;
+ */
+public class JavacTrees extends DocTrees {
+
+    // in a world of a single context per compilation, these would all be final
+    private Resolve resolve;
+    private Enter enter;
+    private Log log;
+    private MemberEnter memberEnter;
+    private Attr attr;
+    private TreeMaker treeMaker;
+    private JavacElements elements;
+    private JavacTaskImpl javacTaskImpl;
+    private Names names;
+    private Types types;
+
+    // called reflectively from Trees.instance(CompilationTask task)
+    public static JavacTrees instance(JavaCompiler.CompilationTask task) {
+        if (!(task instanceof BasicJavacTask))
+            throw new IllegalArgumentException();
+        return instance(((BasicJavacTask)task).getContext());
+    }
+
+    // called reflectively from Trees.instance(ProcessingEnvironment env)
+    public static JavacTrees instance(ProcessingEnvironment env) {
+        if (!(env instanceof JavacProcessingEnvironment))
+            throw new IllegalArgumentException();
+        return instance(((JavacProcessingEnvironment)env).getContext());
+    }
+
+    public static JavacTrees instance(Context context) {
+        JavacTrees instance = context.get(JavacTrees.class);
+        if (instance == null)
+            instance = new JavacTrees(context);
+        return instance;
+    }
+
+    protected JavacTrees(Context context) {
+        context.put(JavacTrees.class, this);
+        init(context);
+    }
+
+    public void updateContext(Context context) {
+        init(context);
+    }
+
+    private void init(Context context) {
+        attr = Attr.instance(context);
+        enter = Enter.instance(context);
+        elements = JavacElements.instance(context);
+        log = Log.instance(context);
+        resolve = Resolve.instance(context);
+        treeMaker = TreeMaker.instance(context);
+        memberEnter = MemberEnter.instance(context);
+        names = Names.instance(context);
+        types = Types.instance(context);
+
+        JavacTask t = context.get(JavacTask.class);
+        if (t instanceof JavacTaskImpl)
+            javacTaskImpl = (JavacTaskImpl) t;
+    }
+
+    public DocSourcePositions getSourcePositions() {
+        return new DocSourcePositions() {
+                public long getStartPosition(CompilationUnitTree file, Tree tree) {
+                    return TreeInfo.getStartPos((JCTree) tree);
+                }
+
+                public long getEndPosition(CompilationUnitTree file, Tree tree) {
+                    EndPosTable endPosTable = ((JCCompilationUnit) file).endPositions;
+                    return TreeInfo.getEndPos((JCTree) tree, endPosTable);
+                }
+
+                public long getStartPosition(CompilationUnitTree file, DocCommentTree comment, DocTree tree) {
+                    return ((DCTree) tree).getSourcePosition((DCDocComment) comment);
+                }
+                @SuppressWarnings("fallthrough")
+                public long getEndPosition(CompilationUnitTree file, DocCommentTree comment, DocTree tree) {
+                    DCDocComment dcComment = (DCDocComment) comment;
+                    if (tree instanceof DCEndPosTree) {
+                        int endPos = ((DCEndPosTree) tree).getEndPos(dcComment);
+
+                        if (endPos != Position.NOPOS) {
+                            return endPos;
+                        }
+                    }
+                    int correction = 0;
+                    switch (tree.getKind()) {
+                        case TEXT:
+                            DCText text = (DCText) tree;
+
+                            return dcComment.comment.getSourcePos(text.pos + text.text.length());
+                        case ERRONEOUS:
+                            DCErroneous err = (DCErroneous) tree;
+
+                            return dcComment.comment.getSourcePos(err.pos + err.body.length());
+                        case IDENTIFIER:
+                            DCIdentifier ident = (DCIdentifier) tree;
+
+                            return dcComment.comment.getSourcePos(ident.pos + (ident.name != names.error ? ident.name.length() : 0));
+                        case PARAM:
+                            DCParam param = (DCParam) tree;
+
+                            if (param.isTypeParameter && param.getDescription().isEmpty()) {
+                                correction = 1;
+                            }
+                        case AUTHOR: case DEPRECATED: case RETURN: case SEE:
+                        case SERIAL: case SERIAL_DATA: case SERIAL_FIELD: case SINCE:
+                        case THROWS: case UNKNOWN_BLOCK_TAG: case VERSION: {
+                            DocTree last = getLastChild(tree);
+
+                            if (last != null) {
+                                return getEndPosition(file, comment, last) + correction;
+                            }
+
+                            DCBlockTag block = (DCBlockTag) tree;
+
+                            return dcComment.comment.getSourcePos(block.pos + block.getTagName().length() + 1);
+                        }
+                        default:
+                            DocTree last = getLastChild(tree);
+
+                            if (last != null) {
+                                return getEndPosition(file, comment, last);
+                            }
+                            break;
+                    }
+
+                    return Position.NOPOS;
+                }
+            };
+    }
+
+    private DocTree getLastChild(DocTree tree) {
+        final DocTree[] last = new DocTree[] {null};
+
+        tree.accept(new DocTreeScanner<Void, Void>() {
+            @Override public Void scan(DocTree node, Void p) {
+                if (node != null) last[0] = node;
+                return null;
+            }
+        }, null);
+
+        return last[0];
+    }
+
+    public JCClassDecl getTree(TypeElement element) {
+        return (JCClassDecl) getTree((Element) element);
+    }
+
+    public JCMethodDecl getTree(ExecutableElement method) {
+        return (JCMethodDecl) getTree((Element) method);
+    }
+
+    public JCTree getTree(Element element) {
+        return getTree(element, null);
+    }
+
+    public JCTree getTree(Element e, AnnotationMirror a) {
+        return getTree(e, a, null);
+    }
+
+    public JCTree getTree(Element e, AnnotationMirror a, AnnotationValue v) {
+        Pair<JCTree, JCCompilationUnit> treeTopLevel = elements.getTreeAndTopLevel(e, a, v);
+        if (treeTopLevel == null)
+            return null;
+        return treeTopLevel.fst;
+    }
+
+    public TreePath getPath(CompilationUnitTree unit, Tree node) {
+        return TreePath.getPath(unit, node);
+    }
+
+    public TreePath getPath(Element e) {
+        return getPath(e, null, null);
+    }
+
+    public TreePath getPath(Element e, AnnotationMirror a) {
+        return getPath(e, a, null);
+    }
+
+    public TreePath getPath(Element e, AnnotationMirror a, AnnotationValue v) {
+        final Pair<JCTree, JCCompilationUnit> treeTopLevel = elements.getTreeAndTopLevel(e, a, v);
+        if (treeTopLevel == null)
+            return null;
+        return TreePath.getPath(treeTopLevel.snd, treeTopLevel.fst);
+    }
+
+    public Symbol getElement(TreePath path) {
+        JCTree tree = (JCTree) path.getLeaf();
+        Symbol sym = TreeInfo.symbolFor(tree);
+        if (sym == null) {
+            if (TreeInfo.isDeclaration(tree)) {
+                for (TreePath p = path; p != null; p = p.getParentPath()) {
+                    JCTree t = (JCTree) p.getLeaf();
+                    if (t.hasTag(JCTree.Tag.CLASSDEF)) {
+                        JCClassDecl ct = (JCClassDecl) t;
+                        if (ct.sym != null) {
+                            if ((ct.sym.flags_field & Flags.UNATTRIBUTED) != 0) {
+                                attr.attribClass(ct.pos(), ct.sym);
+                                sym = TreeInfo.symbolFor(tree);
+                            }
+                            break;
+                        }
+                    }
+                }
+            }
+        }
+        return sym;
+    }
+
+    @Override
+    public Element getElement(DocTreePath path) {
+        DocTree forTree = path.getLeaf();
+        if (forTree instanceof DCReference)
+            return attributeDocReference(path.getTreePath(), ((DCReference) forTree));
+        if (forTree instanceof DCIdentifier) {
+            if (path.getParentPath().getLeaf() instanceof DCParam) {
+                return attributeParamIdentifier(path.getTreePath(), (DCParam) path.getParentPath().getLeaf());
+            }
+        }
+        return null;
+    }
+
+    private Symbol attributeDocReference(TreePath path, DCReference ref) {
+        Env<AttrContext> env = getAttrContext(path);
+
+        Log.DeferredDiagnosticHandler deferredDiagnosticHandler =
+                new Log.DeferredDiagnosticHandler(log);
+        try {
+            final TypeSymbol tsym;
+            final Name memberName;
+            if (ref.qualifierExpression == null) {
+                tsym = env.enclClass.sym;
+                memberName = ref.memberName;
+            } else {
+                // See if the qualifierExpression is a type or package name.
+                // javac does not provide the exact method required, so
+                // we first check if qualifierExpression identifies a type,
+                // and if not, then we check to see if it identifies a package.
+                Type t = attr.attribType(ref.qualifierExpression, env);
+                if (t.isErroneous()) {
+                    if (ref.memberName == null) {
+                        // Attr/Resolve assume packages exist and create symbols as needed
+                        // so use getPackageElement to restrict search to existing packages
+                        PackageSymbol pck = elements.getPackageElement(ref.qualifierExpression.toString());
+                        if (pck != null) {
+                            return pck;
+                        } else if (ref.qualifierExpression.hasTag(JCTree.Tag.IDENT)) {
+                            // fixup:  allow "identifier" instead of "#identifier"
+                            // for compatibility with javadoc
+                            tsym = env.enclClass.sym;
+                            memberName = ((JCIdent) ref.qualifierExpression).name;
+                        } else
+                            return null;
+                    } else {
+                        return null;
+                    }
+                } else {
+                    tsym = t.tsym;
+                    memberName = ref.memberName;
+                }
+            }
+
+            if (memberName == null)
+                return tsym;
+
+            final List<Type> paramTypes;
+            if (ref.paramTypes == null)
+                paramTypes = null;
+            else {
+                ListBuffer<Type> lb = new ListBuffer<>();
+                for (List<JCTree> l = ref.paramTypes; l.nonEmpty(); l = l.tail) {
+                    JCTree tree = l.head;
+                    Type t = attr.attribType(tree, env);
+                    lb.add(t);
+                }
+                paramTypes = lb.toList();
+            }
+
+            ClassSymbol sym = (ClassSymbol) types.cvarUpperBound(tsym.type).tsym;
+
+            Symbol msym = (memberName == sym.name)
+                    ? findConstructor(sym, paramTypes)
+                    : findMethod(sym, memberName, paramTypes);
+            if (paramTypes != null) {
+                // explicit (possibly empty) arg list given, so cannot be a field
+                return msym;
+            }
+
+            VarSymbol vsym = (ref.paramTypes != null) ? null : findField(sym, memberName);
+            // prefer a field over a method with no parameters
+            if (vsym != null &&
+                    (msym == null ||
+                        types.isSubtypeUnchecked(vsym.enclClass().asType(), msym.enclClass().asType()))) {
+                return vsym;
+            } else {
+                return msym;
+            }
+        } catch (Abort e) { // may be thrown by Check.completionError in case of bad class file
+            return null;
+        } finally {
+            log.popDiagnosticHandler(deferredDiagnosticHandler);
+        }
+    }
+
+    private Symbol attributeParamIdentifier(TreePath path, DCParam ptag) {
+        Symbol javadocSymbol = getElement(path);
+        if (javadocSymbol == null)
+            return null;
+        ElementKind kind = javadocSymbol.getKind();
+        List<? extends Symbol> params = List.nil();
+        if (kind == ElementKind.METHOD || kind == ElementKind.CONSTRUCTOR) {
+            MethodSymbol ee = (MethodSymbol) javadocSymbol;
+            params = ptag.isTypeParameter()
+                    ? ee.getTypeParameters()
+                    : ee.getParameters();
+        } else if (kind.isClass() || kind.isInterface()) {
+            ClassSymbol te = (ClassSymbol) javadocSymbol;
+            params = te.getTypeParameters();
+        }
+
+        for (Symbol param : params) {
+            if (param.getSimpleName() == ptag.getName().getName()) {
+                return param;
+            }
+        }
+        return null;
+    }
+
+    /** @see com.sun.tools.javadoc.ClassDocImpl#findField */
+    private VarSymbol findField(ClassSymbol tsym, Name fieldName) {
+        return searchField(tsym, fieldName, new HashSet<ClassSymbol>());
+    }
+
+    /** @see com.sun.tools.javadoc.ClassDocImpl#searchField */
+    private VarSymbol searchField(ClassSymbol tsym, Name fieldName, Set<ClassSymbol> searched) {
+        if (searched.contains(tsym)) {
+            return null;
+        }
+        searched.add(tsym);
+
+        for (Symbol sym : tsym.members().getSymbolsByName(fieldName)) {
+            if (sym.kind == Kinds.VAR) {
+                return (VarSymbol)sym;
+            }
+        }
+
+        //### If we found a VarSymbol above, but which did not pass
+        //### the modifier filter, we should return failure here!
+
+        ClassSymbol encl = tsym.owner.enclClass();
+        if (encl != null) {
+            VarSymbol vsym = searchField(encl, fieldName, searched);
+            if (vsym != null) {
+                return vsym;
+            }
+        }
+
+        // search superclass
+        Type superclass = tsym.getSuperclass();
+        if (superclass.tsym != null) {
+            VarSymbol vsym = searchField((ClassSymbol) superclass.tsym, fieldName, searched);
+            if (vsym != null) {
+                return vsym;
+            }
+        }
+
+        // search interfaces
+        List<Type> intfs = tsym.getInterfaces();
+        for (List<Type> l = intfs; l.nonEmpty(); l = l.tail) {
+            Type intf = l.head;
+            if (intf.isErroneous()) continue;
+            VarSymbol vsym = searchField((ClassSymbol) intf.tsym, fieldName, searched);
+            if (vsym != null) {
+                return vsym;
+            }
+        }
+
+        return null;
+    }
+
+    /** @see com.sun.tools.javadoc.ClassDocImpl#findConstructor */
+    MethodSymbol findConstructor(ClassSymbol tsym, List<Type> paramTypes) {
+        for (Symbol sym : tsym.members().getSymbolsByName(names.init)) {
+            if (sym.kind == Kinds.MTH) {
+                if (hasParameterTypes((MethodSymbol) sym, paramTypes)) {
+                    return (MethodSymbol) sym;
+                }
+            }
+        }
+        return null;
+    }
+
+    /** @see com.sun.tools.javadoc.ClassDocImpl#findMethod */
+    private MethodSymbol findMethod(ClassSymbol tsym, Name methodName, List<Type> paramTypes) {
+        return searchMethod(tsym, methodName, paramTypes, new HashSet<ClassSymbol>());
+    }
+
+    /** @see com.sun.tools.javadoc.ClassDocImpl#searchMethod */
+    private MethodSymbol searchMethod(ClassSymbol tsym, Name methodName,
+                                       List<Type> paramTypes, Set<ClassSymbol> searched) {
+        //### Note that this search is not necessarily what the compiler would do!
+
+        // do not match constructors
+        if (methodName == names.init)
+            return null;
+
+        if (searched.contains(tsym))
+            return null;
+        searched.add(tsym);
+
+        // search current class
+
+        //### Using modifier filter here isn't really correct,
+        //### but emulates the old behavior.  Instead, we should
+        //### apply the normal rules of visibility and inheritance.
+
+        if (paramTypes == null) {
+            // If no parameters specified, we are allowed to return
+            // any method with a matching name.  In practice, the old
+            // code returned the first method, which is now the last!
+            // In order to provide textually identical results, we
+            // attempt to emulate the old behavior.
+            MethodSymbol lastFound = null;
+            for (Symbol sym : tsym.members().getSymbolsByName(methodName)) {
+                if (sym.kind == Kinds.MTH) {
+                    if (sym.name == methodName) {
+                        lastFound = (MethodSymbol)sym;
+                    }
+                }
+            }
+            if (lastFound != null) {
+                return lastFound;
+            }
+        } else {
+            for (Symbol sym : tsym.members().getSymbolsByName(methodName)) {
+                if (sym != null &&
+                    sym.kind == Kinds.MTH) {
+                    if (hasParameterTypes((MethodSymbol) sym, paramTypes)) {
+                        return (MethodSymbol) sym;
+                    }
+                }
+            }
+        }
+
+        //### If we found a MethodSymbol above, but which did not pass
+        //### the modifier filter, we should return failure here!
+
+        // search superclass
+        Type superclass = tsym.getSuperclass();
+        if (superclass.tsym != null) {
+            MethodSymbol msym = searchMethod((ClassSymbol) superclass.tsym, methodName, paramTypes, searched);
+            if (msym != null) {
+                return msym;
+            }
+        }
+
+        // search interfaces
+        List<Type> intfs = tsym.getInterfaces();
+        for (List<Type> l = intfs; l.nonEmpty(); l = l.tail) {
+            Type intf = l.head;
+            if (intf.isErroneous()) continue;
+            MethodSymbol msym = searchMethod((ClassSymbol) intf.tsym, methodName, paramTypes, searched);
+            if (msym != null) {
+                return msym;
+            }
+        }
+
+        // search enclosing class
+        ClassSymbol encl = tsym.owner.enclClass();
+        if (encl != null) {
+            MethodSymbol msym = searchMethod(encl, methodName, paramTypes, searched);
+            if (msym != null) {
+                return msym;
+            }
+        }
+
+        return null;
+    }
+
+    /** @see com.sun.tools.javadoc.ClassDocImpl */
+    private boolean hasParameterTypes(MethodSymbol method, List<Type> paramTypes) {
+        if (paramTypes == null)
+            return true;
+
+        if (method.params().size() != paramTypes.size())
+            return false;
+
+        List<Type> methodParamTypes = types.erasureRecursive(method.asType()).getParameterTypes();
+
+        return (Type.isErroneous(paramTypes))
+            ? fuzzyMatch(paramTypes, methodParamTypes)
+            : types.isSameTypes(paramTypes, methodParamTypes);
+    }
+
+    boolean fuzzyMatch(List<Type> paramTypes, List<Type> methodParamTypes) {
+        List<Type> l1 = paramTypes;
+        List<Type> l2 = methodParamTypes;
+        while (l1.nonEmpty()) {
+            if (!fuzzyMatch(l1.head, l2.head))
+                return false;
+            l1 = l1.tail;
+            l2 = l2.tail;
+        }
+        return true;
+    }
+
+    boolean fuzzyMatch(Type paramType, Type methodParamType) {
+        Boolean b = fuzzyMatcher.visit(paramType, methodParamType);
+        return (b == Boolean.TRUE);
+    }
+
+    TypeRelation fuzzyMatcher = new TypeRelation() {
+        @Override
+        public Boolean visitType(Type t, Type s) {
+            if (t == s)
+                return true;
+
+            if (s.isPartial())
+                return visit(s, t);
+
+            switch (t.getTag()) {
+            case BYTE: case CHAR: case SHORT: case INT: case LONG: case FLOAT:
+            case DOUBLE: case BOOLEAN: case VOID: case BOT: case NONE:
+                return t.hasTag(s.getTag());
+            default:
+                throw new AssertionError("fuzzyMatcher " + t.getTag());
+            }
+        }
+
+        @Override
+        public Boolean visitArrayType(ArrayType t, Type s) {
+            if (t == s)
+                return true;
+
+            if (s.isPartial())
+                return visit(s, t);
+
+            return s.hasTag(ARRAY)
+                && visit(t.elemtype, types.elemtype(s));
+        }
+
+        @Override
+        public Boolean visitClassType(ClassType t, Type s) {
+            if (t == s)
+                return true;
+
+            if (s.isPartial())
+                return visit(s, t);
+
+            return t.tsym == s.tsym;
+        }
+
+        @Override
+        public Boolean visitErrorType(ErrorType t, Type s) {
+            return s.hasTag(CLASS)
+                    && t.tsym.name == ((ClassType) s).tsym.name;
+        }
+    };
+
+    public TypeMirror getTypeMirror(TreePath path) {
+        Tree t = path.getLeaf();
+        return ((JCTree)t).type;
+    }
+
+    public JavacScope getScope(TreePath path) {
+        return JavacScope.create(getAttrContext(path));
+    }
+
+    public String getDocComment(TreePath path) {
+        CompilationUnitTree t = path.getCompilationUnit();
+        Tree leaf = path.getLeaf();
+        if (t instanceof JCTree.JCCompilationUnit && leaf instanceof JCTree) {
+            JCCompilationUnit cu = (JCCompilationUnit) t;
+            if (cu.docComments != null) {
+                return cu.docComments.getCommentText((JCTree) leaf);
+            }
+        }
+        return null;
+    }
+
+    public DocCommentTree getDocCommentTree(TreePath path) {
+        CompilationUnitTree t = path.getCompilationUnit();
+        Tree leaf = path.getLeaf();
+        if (t instanceof JCTree.JCCompilationUnit && leaf instanceof JCTree) {
+            JCCompilationUnit cu = (JCCompilationUnit) t;
+            if (cu.docComments != null) {
+                return cu.docComments.getCommentTree((JCTree) leaf);
+            }
+        }
+        return null;
+    }
+
+    public boolean isAccessible(Scope scope, TypeElement type) {
+        if (scope instanceof JavacScope && type instanceof ClassSymbol) {
+            Env<AttrContext> env = ((JavacScope) scope).env;
+            return resolve.isAccessible(env, (ClassSymbol)type, true);
+        } else
+            return false;
+    }
+
+    public boolean isAccessible(Scope scope, Element member, DeclaredType type) {
+        if (scope instanceof JavacScope
+                && member instanceof Symbol
+                && type instanceof com.sun.tools.javac.code.Type) {
+            Env<AttrContext> env = ((JavacScope) scope).env;
+            return resolve.isAccessible(env, (com.sun.tools.javac.code.Type)type, (Symbol)member, true);
+        } else
+            return false;
+    }
+
+    private Env<AttrContext> getAttrContext(TreePath path) {
+        if (!(path.getLeaf() instanceof JCTree))  // implicit null-check
+            throw new IllegalArgumentException();
+
+        // if we're being invoked from a Tree API client via parse/enter/analyze,
+        // we need to make sure all the classes have been entered;
+        // if we're being invoked from JSR 199 or JSR 269, then the classes
+        // will already have been entered.
+        if (javacTaskImpl != null) {
+            try {
+                javacTaskImpl.enter(null);
+            } catch (IOException e) {
+                throw new Error("unexpected error while entering symbols: " + e);
+            }
+        }
+
+
+        JCCompilationUnit unit = (JCCompilationUnit) path.getCompilationUnit();
+        Copier copier = createCopier(treeMaker.forToplevel(unit));
+
+        Env<AttrContext> env = null;
+        JCMethodDecl method = null;
+        JCVariableDecl field = null;
+
+        List<Tree> l = List.nil();
+        TreePath p = path;
+        while (p != null) {
+            l = l.prepend(p.getLeaf());
+            p = p.getParentPath();
+        }
+
+        for ( ; l.nonEmpty(); l = l.tail) {
+            Tree tree = l.head;
+            switch (tree.getKind()) {
+                case COMPILATION_UNIT:
+//                    System.err.println("COMP: " + ((JCCompilationUnit)tree).sourcefile);
+                    env = enter.getTopLevelEnv((JCCompilationUnit)tree);
+                    break;
+                case ANNOTATION_TYPE:
+                case CLASS:
+                case ENUM:
+                case INTERFACE:
+//                    System.err.println("CLASS: " + ((JCClassDecl)tree).sym.getSimpleName());
+                    env = enter.getClassEnv(((JCClassDecl)tree).sym);
+                    break;
+                case METHOD:
+//                    System.err.println("METHOD: " + ((JCMethodDecl)tree).sym.getSimpleName());
+                    method = (JCMethodDecl)tree;
+                    env = memberEnter.getMethodEnv(method, env);
+                    break;
+                case VARIABLE:
+//                    System.err.println("FIELD: " + ((JCVariableDecl)tree).sym.getSimpleName());
+                    field = (JCVariableDecl)tree;
+                    break;
+                case BLOCK: {
+//                    System.err.println("BLOCK: ");
+                    if (method != null) {
+                        try {
+                            Assert.check(method.body == tree);
+                            method.body = copier.copy((JCBlock)tree, (JCTree) path.getLeaf());
+                            env = attribStatToTree(method.body, env, copier.leafCopy);
+                        } finally {
+                            method.body = (JCBlock) tree;
+                        }
+                    } else {
+                        JCBlock body = copier.copy((JCBlock)tree, (JCTree) path.getLeaf());
+                        env = attribStatToTree(body, env, copier.leafCopy);
+                    }
+                    return env;
+                }
+                default:
+//                    System.err.println("DEFAULT: " + tree.getKind());
+                    if (field != null && field.getInitializer() == tree) {
+                        env = memberEnter.getInitEnv(field, env);
+                        JCExpression expr = copier.copy((JCExpression)tree, (JCTree) path.getLeaf());
+                        env = attribExprToTree(expr, env, copier.leafCopy);
+                        return env;
+                    }
+            }
+        }
+        return (field != null) ? memberEnter.getInitEnv(field, env) : env;
+    }
+
+    private Env<AttrContext> attribStatToTree(JCTree stat, Env<AttrContext>env, JCTree tree) {
+        JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
+        try {
+            return attr.attribStatToTree(stat, env, tree);
+        } finally {
+            log.useSource(prev);
+        }
+    }
+
+    private Env<AttrContext> attribExprToTree(JCExpression expr, Env<AttrContext>env, JCTree tree) {
+        JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
+        try {
+            return attr.attribExprToTree(expr, env, tree);
+        } finally {
+            log.useSource(prev);
+        }
+    }
+
+    /**
+     * Makes a copy of a tree, noting the value resulting from copying a particular leaf.
+     **/
+    protected static class Copier extends TreeCopier<JCTree> {
+        JCTree leafCopy = null;
+
+        protected Copier(TreeMaker M) {
+            super(M);
+        }
+
+        @Override
+        public <T extends JCTree> T copy(T t, JCTree leaf) {
+            T t2 = super.copy(t, leaf);
+            if (t == leaf)
+                leafCopy = t2;
+            return t2;
+        }
+    }
+
+    protected Copier createCopier(TreeMaker maker) {
+        return new Copier(maker);
+    }
+
+    /**
+     * Returns the original type from the ErrorType object.
+     * @param errorType The errorType for which we want to get the original type.
+     * @returns TypeMirror corresponding to the original type, replaced by the ErrorType.
+     *          noType (type.tag == NONE) is returned if there is no original type.
+     */
+    public TypeMirror getOriginalType(javax.lang.model.type.ErrorType errorType) {
+        if (errorType instanceof com.sun.tools.javac.code.Type.ErrorType) {
+            return ((com.sun.tools.javac.code.Type.ErrorType)errorType).getOriginalType();
+        }
+
+        return com.sun.tools.javac.code.Type.noType;
+    }
+
+    /**
+     * Prints a message of the specified kind at the location of the
+     * tree within the provided compilation unit
+     *
+     * @param kind the kind of message
+     * @param msg  the message, or an empty string if none
+     * @param t    the tree to use as a position hint
+     * @param root the compilation unit that contains tree
+     */
+    public void printMessage(Diagnostic.Kind kind, CharSequence msg,
+            com.sun.source.tree.Tree t,
+            com.sun.source.tree.CompilationUnitTree root) {
+        printMessage(kind, msg, ((JCTree) t).pos(), root);
+    }
+
+    public void printMessage(Diagnostic.Kind kind, CharSequence msg,
+            com.sun.source.doctree.DocTree t,
+            com.sun.source.doctree.DocCommentTree c,
+            com.sun.source.tree.CompilationUnitTree root) {
+        printMessage(kind, msg, ((DCTree) t).pos((DCDocComment) c), root);
+    }
+
+    private void printMessage(Diagnostic.Kind kind, CharSequence msg,
+            JCDiagnostic.DiagnosticPosition pos,
+            com.sun.source.tree.CompilationUnitTree root) {
+        JavaFileObject oldSource = null;
+        JavaFileObject newSource = null;
+
+        newSource = root.getSourceFile();
+        if (newSource == null) {
+            pos = null;
+        } else {
+            oldSource = log.useSource(newSource);
+        }
+
+        try {
+            switch (kind) {
+            case ERROR:
+                boolean prev = log.multipleErrors;
+                try {
+                    log.error(pos, "proc.messager", msg.toString());
+                } finally {
+                    log.multipleErrors = prev;
+                }
+                break;
+
+            case WARNING:
+                log.warning(pos, "proc.messager", msg.toString());
+                break;
+
+            case MANDATORY_WARNING:
+                log.mandatoryWarning(pos, "proc.messager", msg.toString());
+                break;
+
+            default:
+                log.note(pos, "proc.messager", msg.toString());
+            }
+        } finally {
+            if (oldSource != null)
+                log.useSource(oldSource);
+        }
+    }
+
+    @Override
+    public TypeMirror getLub(CatchTree tree) {
+        JCCatch ct = (JCCatch) tree;
+        JCVariableDecl v = ct.param;
+        if (v.type != null && v.type.getKind() == TypeKind.UNION) {
+            UnionClassType ut = (UnionClassType) v.type;
+            return ut.getLub();
+        } else {
+            return v.type;
+        }
+    }
+}