/*

 * Copyright (c) 1999, 2011, 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.tree;

import java.util.*;

import java.io.IOException;

import java.io.StringWriter;

import javax.lang.model.element.Modifier;

import javax.lang.model.type.TypeKind;

import javax.tools.JavaFileObject;

import com.sun.tools.javac.util.*;

import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;

import com.sun.tools.javac.util.List;

import com.sun.tools.javac.code.*;

import com.sun.tools.javac.code.Scope.*;

import com.sun.tools.javac.code.Symbol.*;

import com.sun.source.tree.*;

import static com.sun.tools.javac.code.BoundKind.*;

/**

 * Root class for abstract syntax tree nodes. It provides definitions

 * for specific tree nodes as subclasses nested inside.

 *

 * <p>Each subclass is highly standardized.  It generally contains

 * only tree fields for the syntactic subcomponents of the node.  Some

 * classes that represent identifier uses or definitions also define a

 * Symbol field that denotes the represented identifier.  Classes for

 * non-local jumps also carry the jump target as a field.  The root

 * class Tree itself defines fields for the tree's type and position.

 * No other fields are kept in a tree node; instead parameters are

 * passed to methods accessing the node.

 *

 * <p>Except for the methods defined by com.sun.source, the only

 * method defined in subclasses is `visit' which applies a given

 * visitor to the tree. The actual tree processing is done by visitor

 * classes in other packages. The abstract class Visitor, as well as

 * an Factory interface for trees, are defined as inner classes in

 * Tree.

 *

 * <p>To avoid ambiguities with the Tree API in com.sun.source all sub

 * classes should, by convention, start with JC (javac).

 *

 * <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>

 *

 * @see TreeMaker

 * @see TreeInfo

 * @see TreeTranslator

 * @see Pretty

 */

public abstract class JCTree implements Tree, Cloneable, DiagnosticPosition {

    /* Tree tag values, identifying kinds of trees */

    /** Toplevel nodes, of type TopLevel, representing entire source files.

     */

    public static final int  TOPLEVEL = 1;

    /** Import clauses, of type Import.

     */

    public static final int IMPORT = TOPLEVEL + 1;

    /** Class definitions, of type ClassDef.

     */

    public static final int CLASSDEF = IMPORT + 1;

    /** Method definitions, of type MethodDef.

     */

    public static final int METHODDEF = CLASSDEF + 1;

    /** Variable definitions, of type VarDef.

     */

    public static final int VARDEF = METHODDEF + 1;

    /** The no-op statement ";", of type Skip

     */

    public static final int SKIP = VARDEF + 1;

    /** Blocks, of type Block.

     */

    public static final int BLOCK = SKIP + 1;

    /** Do-while loops, of type DoLoop.

     */

    public static final int DOLOOP = BLOCK + 1;

    /** While-loops, of type WhileLoop.

     */

    public static final int WHILELOOP = DOLOOP + 1;

    /** For-loops, of type ForLoop.

     */

    public static final int FORLOOP = WHILELOOP + 1;

    /** Foreach-loops, of type ForeachLoop.

     */

    public static final int FOREACHLOOP = FORLOOP + 1;

    /** Labelled statements, of type Labelled.

     */

    public static final int LABELLED = FOREACHLOOP + 1;

    /** Switch statements, of type Switch.

     */

    public static final int SWITCH = LABELLED + 1;

    /** Case parts in switch statements, of type Case.

     */

    public static final int CASE = SWITCH + 1;

    /** Synchronized statements, of type Synchonized.

     */

    public static final int SYNCHRONIZED = CASE + 1;

    /** Try statements, of type Try.

     */

    public static final int TRY = SYNCHRONIZED + 1;

    /** Catch clauses in try statements, of type Catch.

     */

    public static final int CATCH = TRY + 1;

    /** Conditional expressions, of type Conditional.

     */

    public static final int CONDEXPR = CATCH + 1;

    /** Conditional statements, of type If.

     */

    public static final int IF = CONDEXPR + 1;

    /** Expression statements, of type Exec.

     */

    public static final int EXEC = IF + 1;

    /** Break statements, of type Break.

     */

    public static final int BREAK = EXEC + 1;

    /** Continue statements, of type Continue.

     */

    public static final int CONTINUE = BREAK + 1;

    /** Return statements, of type Return.

     */

    public static final int RETURN = CONTINUE + 1;

    /** Throw statements, of type Throw.

     */

    public static final int THROW = RETURN + 1;

    /** Assert statements, of type Assert.

     */

    public static final int ASSERT = THROW + 1;

    /** Method invocation expressions, of type Apply.

     */

    public static final int APPLY = ASSERT + 1;

    /** Class instance creation expressions, of type NewClass.

     */

    public static final int NEWCLASS = APPLY + 1;

    /** Array creation expressions, of type NewArray.

     */

    public static final int NEWARRAY = NEWCLASS + 1;

    /** Parenthesized subexpressions, of type Parens.

     */

    public static final int PARENS = NEWARRAY + 1;

    /** Assignment expressions, of type Assign.

     */

    public static final int ASSIGN = PARENS + 1;

    /** Type cast expressions, of type TypeCast.

     */

    public static final int TYPECAST = ASSIGN + 1;

    /** Type test expressions, of type TypeTest.

     */

    public static final int TYPETEST = TYPECAST + 1;

    /** Indexed array expressions, of type Indexed.

     */

    public static final int INDEXED = TYPETEST + 1;

    /** Selections, of type Select.

     */

    public static final int SELECT = INDEXED + 1;

    /** Simple identifiers, of type Ident.

     */

    public static final int IDENT = SELECT + 1;

    /** Literals, of type Literal.

     */

    public static final int LITERAL = IDENT + 1;

    /** Basic type identifiers, of type TypeIdent.

     */

    public static final int TYPEIDENT = LITERAL + 1;

    /** Array types, of type TypeArray.

     */

    public static final int TYPEARRAY = TYPEIDENT + 1;

    /** Parameterized types, of type TypeApply.

     */

    public static final int TYPEAPPLY = TYPEARRAY + 1;

    /** Disjunction types, of type TypeDisjunction

     */

    public static final int TYPEDISJUNCTION = TYPEAPPLY + 1;

    /** Formal type parameters, of type TypeParameter.

     */

    public static final int TYPEPARAMETER = TYPEDISJUNCTION + 1;

    /** Type argument.

     */

    public static final int WILDCARD = TYPEPARAMETER + 1;

    /** Bound kind: extends, super, exact, or unbound

     */

    public static final int TYPEBOUNDKIND = WILDCARD + 1;

    /** metadata: Annotation.

     */

    public static final int ANNOTATION = TYPEBOUNDKIND + 1;

    /** metadata: Modifiers

     */

    public static final int MODIFIERS = ANNOTATION + 1;

    public static final int ANNOTATED_TYPE = MODIFIERS + 1;

    /** Error trees, of type Erroneous.

     */

    public static final int ERRONEOUS = ANNOTATED_TYPE + 1;

    /** Unary operators, of type Unary.

     */

    public static final int POS = ERRONEOUS + 1;             // +

    public static final int NEG = POS + 1;                   // -

    public static final int NOT = NEG + 1;                   // !

    public static final int COMPL = NOT + 1;                 // ~

    public static final int PREINC = COMPL + 1;              // ++ _

    public static final int PREDEC = PREINC + 1;             // -- _

    public static final int POSTINC = PREDEC + 1;            // _ ++

    public static final int POSTDEC = POSTINC + 1;           // _ --

    /** unary operator for null reference checks, only used internally.

     */

    public static final int NULLCHK = POSTDEC + 1;

    /** Binary operators, of type Binary.

     */

    public static final int OR = NULLCHK + 1;                // ||

    public static final int AND = OR + 1;                    // &&

    public static final int BITOR = AND + 1;                 // |

    public static final int BITXOR = BITOR + 1;              // ^

    public static final int BITAND = BITXOR + 1;             // &

    public static final int EQ = BITAND + 1;                 // ==

    public static final int NE = EQ + 1;                     // !=

    public static final int LT = NE + 1;                     // <

    public static final int GT = LT + 1;                     // >

    public static final int LE = GT + 1;                     // <=

    public static final int GE = LE + 1;                     // >=

    public static final int SL = GE + 1;                     // <<

    public static final int SR = SL + 1;                     // >>

    public static final int USR = SR + 1;                    // >>>

    public static final int PLUS = USR + 1;                  // +

    public static final int MINUS = PLUS + 1;                // -

    public static final int MUL = MINUS + 1;                 // *

    public static final int DIV = MUL + 1;                   // /

    public static final int MOD = DIV + 1;                   // %

    /** Assignment operators, of type Assignop.

     */

    public static final int BITOR_ASG = MOD + 1;             // |=

    public static final int BITXOR_ASG = BITOR_ASG + 1;      // ^=

    public static final int BITAND_ASG = BITXOR_ASG + 1;     // &=

    public static final int SL_ASG = SL + BITOR_ASG - BITOR; // <<=

    public static final int SR_ASG = SL_ASG + 1;             // >>=

    public static final int USR_ASG = SR_ASG + 1;            // >>>=

    public static final int PLUS_ASG = USR_ASG + 1;          // +=

    public static final int MINUS_ASG = PLUS_ASG + 1;        // -=

    public static final int MUL_ASG = MINUS_ASG + 1;         // *=

    public static final int DIV_ASG = MUL_ASG + 1;           // /=

    public static final int MOD_ASG = DIV_ASG + 1;           // %=

    /** A synthetic let expression, of type LetExpr.

     */

    public static final int LETEXPR = MOD_ASG + 1;           // ala scheme

    /** The offset between assignment operators and normal operators.

     */

    public static final int ASGOffset = BITOR_ASG - BITOR;

    /* The (encoded) position in the source file. @see util.Position.

     */

    public int pos;

    /* The type of this node.

     */

    public Type type;

    /* The tag of this node -- one of the constants declared above.

     */

    public abstract int getTag();

    /** Convert a tree to a pretty-printed string. */

    @Override

    public String toString() {

        StringWriter s = new StringWriter();

        try {

            new Pretty(s, false).printExpr(this);

        }

        catch (IOException e) {

            // should never happen, because StringWriter is defined

            // never to throw any IOExceptions

            throw new AssertionError(e);

        }

        return s.toString();

    }

    /** Set position field and return this tree.

     */

    public JCTree setPos(int pos) {

        this.pos = pos;

        return this;

    }

    /** Set type field and return this tree.

     */

    public JCTree setType(Type type) {

        this.type = type;

        return this;

    }

    /** Visit this tree with a given visitor.

     */

    public abstract void accept(Visitor v);

    public abstract <R,D> R accept(TreeVisitor<R,D> v, D d);

    /** Return a shallow copy of this tree.

     */

    @Override

    public Object clone() {

        try {

            return super.clone();

        } catch(CloneNotSupportedException e) {

            throw new RuntimeException(e);

        }

    }

    /** Get a default position for this tree node.

     */

    public DiagnosticPosition pos() {

        return this;

    }

    // for default DiagnosticPosition

    public JCTree getTree() {

        return this;

    }

    // for default DiagnosticPosition

    public int getStartPosition() {

        return TreeInfo.getStartPos(this);

    }

    // for default DiagnosticPosition

    public int getPreferredPosition() {

        return pos;

    }

    // for default DiagnosticPosition

    public int getEndPosition(Map<JCTree, Integer> endPosTable) {

        return TreeInfo.getEndPos(this, endPosTable);

    }

    /**

     * Everything in one source file is kept in a TopLevel structure.

     * @param pid              The tree representing the package clause.

     * @param sourcefile       The source file name.

     * @param defs             All definitions in this file (ClassDef, Import, and Skip)

     * @param packge           The package it belongs to.

     * @param namedImportScope A scope for all named imports.

     * @param starImportScope  A scope for all import-on-demands.

     * @param lineMap          Line starting positions, defined only

     *                         if option -g is set.

     * @param docComments      A hashtable that stores all documentation comments

     *                         indexed by the tree nodes they refer to.

     *                         defined only if option -s is set.

     * @param endPositions     A hashtable that stores ending positions of source

     *                         ranges indexed by the tree nodes they belong to.

     *                         Defined only if option -Xjcov is set.

     */

    public static class JCCompilationUnit extends JCTree implements CompilationUnitTree {

        public List<JCAnnotation> packageAnnotations;

        public JCExpression pid;

        public List<JCTree> defs;

        public JavaFileObject sourcefile;

        public PackageSymbol packge;

        public ImportScope namedImportScope;

        public StarImportScope starImportScope;

        public long flags;

        public Position.LineMap lineMap = null;

        public Map<JCTree, String> docComments = null;

        public Map<JCTree, Integer> endPositions = null;

        protected JCCompilationUnit(List<JCAnnotation> packageAnnotations,

                        JCExpression pid,

                        List<JCTree> defs,

                        JavaFileObject sourcefile,

                        PackageSymbol packge,

                        ImportScope namedImportScope,

                        StarImportScope starImportScope) {

            this.packageAnnotations = packageAnnotations;

            this.pid = pid;

            this.defs = defs;

            this.sourcefile = sourcefile;

            this.packge = packge;

            this.namedImportScope = namedImportScope;

            this.starImportScope = starImportScope;

        }

        @Override

        public void accept(Visitor v) { v.visitTopLevel(this); }

        public Kind getKind() { return Kind.COMPILATION_UNIT; }

        public List<JCAnnotation> getPackageAnnotations() {

            return packageAnnotations;

        }

        public List<JCImport> getImports() {

            ListBuffer<JCImport> imports = new ListBuffer<JCImport>();

            for (JCTree tree : defs) {

                if (tree.getTag() == IMPORT)

                    imports.append((JCImport)tree);

                else

                    break;

            }

            return imports.toList();

        }

        public JCExpression getPackageName() { return pid; }

        public JavaFileObject getSourceFile() {

            return sourcefile;

        }

        public Position.LineMap getLineMap() {

            return lineMap;

        }

        public List<JCTree> getTypeDecls() {

            List<JCTree> typeDefs;

            for (typeDefs = defs; !typeDefs.isEmpty(); typeDefs = typeDefs.tail)

                if (typeDefs.head.getTag() != IMPORT)

                    break;

            return typeDefs;

        }

        @Override

        public <R,D> R accept(TreeVisitor<R,D> v, D d) {

            return v.visitCompilationUnit(this, d);

        }

        @Override

        public int getTag() {

            return TOPLEVEL;

        }

    }

    /**

     * An import clause.

     * @param qualid    The imported class(es).

     */

    public static class JCImport extends JCTree implements ImportTree {

        public boolean staticImport;

        public JCTree qualid;

        protected JCImport(JCTree qualid, boolean importStatic) {

            this.qualid = qualid;

            this.staticImport = importStatic;

        }

        @Override

        public void accept(Visitor v) { v.visitImport(this); }

        public boolean isStatic() { return staticImport; }

        public JCTree getQualifiedIdentifier() { return qualid; }

        public Kind getKind() { return Kind.IMPORT; }

        @Override

        public <R,D> R accept(TreeVisitor<R,D> v, D d) {

            return v.visitImport(this, d);

        }

        @Override

        public int getTag() {

            return IMPORT;