Symtab.java revision 3231:50467a1cf5b1 
1/*
2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package com.sun.tools.javac.code;
27
28import java.util.HashMap;
29import java.util.Map;
30
31import javax.lang.model.element.ElementVisitor;
32import javax.tools.JavaFileObject;
33
34
35import com.sun.tools.javac.code.Scope.WriteableScope;
36import com.sun.tools.javac.code.Symbol.ClassSymbol;
37import com.sun.tools.javac.code.Symbol.Completer;
38import com.sun.tools.javac.code.Symbol.CompletionFailure;
39import com.sun.tools.javac.code.Symbol.MethodSymbol;
40import com.sun.tools.javac.code.Symbol.PackageSymbol;
41import com.sun.tools.javac.code.Symbol.TypeSymbol;
42import com.sun.tools.javac.code.Symbol.VarSymbol;
43import com.sun.tools.javac.code.Type.BottomType;
44import com.sun.tools.javac.code.Type.ClassType;
45import com.sun.tools.javac.code.Type.ErrorType;
46import com.sun.tools.javac.code.Type.JCPrimitiveType;
47import com.sun.tools.javac.code.Type.JCVoidType;
48import com.sun.tools.javac.code.Type.MethodType;
49import com.sun.tools.javac.code.Type.UnknownType;
50import com.sun.tools.javac.jvm.Target;
51import com.sun.tools.javac.util.Assert;
52import com.sun.tools.javac.util.Context;
53import com.sun.tools.javac.util.Convert;
54import com.sun.tools.javac.util.DefinedBy;
55import com.sun.tools.javac.util.DefinedBy.Api;
56import com.sun.tools.javac.util.JavacMessages;
57import com.sun.tools.javac.util.List;
58import com.sun.tools.javac.util.Log;
59import com.sun.tools.javac.util.Name;
60import com.sun.tools.javac.util.Names;
61
62import static com.sun.tools.javac.code.Flags.*;
63import static com.sun.tools.javac.code.Kinds.Kind.*;
64import static com.sun.tools.javac.code.TypeTag.*;
65
66/** A class that defines all predefined constants and operators
67 *  as well as special classes such as java.lang.Object, which need
68 *  to be known to the compiler. All symbols are held in instance
69 *  fields. This makes it possible to work in multiple concurrent
70 *  projects, which might use different class files for library classes.
71 *
72 *  <p><b>This is NOT part of any supported API.
73 *  If you write code that depends on this, you do so at your own risk.
74 *  This code and its internal interfaces are subject to change or
75 *  deletion without notice.</b>
76 */
77public class Symtab {
78    /** The context key for the symbol table. */
79    protected static final Context.Key<Symtab> symtabKey = new Context.Key<>();
80
81    /** Get the symbol table instance. */
82    public static Symtab instance(Context context) {
83        Symtab instance = context.get(symtabKey);
84        if (instance == null)
85            instance = new Symtab(context);
86        return instance;
87    }
88
89    /** Builtin types.
90     */
91    public final JCPrimitiveType byteType = new JCPrimitiveType(BYTE, null);
92    public final JCPrimitiveType charType = new JCPrimitiveType(CHAR, null);
93    public final JCPrimitiveType shortType = new JCPrimitiveType(SHORT, null);
94    public final JCPrimitiveType intType = new JCPrimitiveType(INT, null);
95    public final JCPrimitiveType longType = new JCPrimitiveType(LONG, null);
96    public final JCPrimitiveType floatType = new JCPrimitiveType(FLOAT, null);
97    public final JCPrimitiveType doubleType = new JCPrimitiveType(DOUBLE, null);
98    public final JCPrimitiveType booleanType = new JCPrimitiveType(BOOLEAN, null);
99    public final Type botType = new BottomType();
100    public final JCVoidType voidType = new JCVoidType();
101
102    private final Names names;
103    private final Completer initialCompleter;
104    private final Target target;
105
106    /** A symbol for the root package.
107     */
108    public final PackageSymbol rootPackage;
109
110    /** A symbol for the unnamed package.
111     */
112    public final PackageSymbol unnamedPackage;
113
114    /** A symbol that stands for a missing symbol.
115     */
116    public final TypeSymbol noSymbol;
117
118    /** The error symbol.
119     */
120    public final ClassSymbol errSymbol;
121
122    /** The unknown symbol.
123     */
124    public final ClassSymbol unknownSymbol;
125
126    /** A value for the errType, with a originalType of noType */
127    public final Type errType;
128
129    /** A value for the unknown type. */
130    public final Type unknownType;
131
132    /** The builtin type of all arrays. */
133    public final ClassSymbol arrayClass;
134    public final MethodSymbol arrayCloneMethod;
135
136    /** VGJ: The (singleton) type of all bound types. */
137    public final ClassSymbol boundClass;
138
139    /** The builtin type of all methods. */
140    public final ClassSymbol methodClass;
141
142    /** Predefined types.
143     */
144    public final Type objectType;
145    public final Type objectsType;
146    public final Type classType;
147    public final Type classLoaderType;
148    public final Type stringType;
149    public final Type stringBufferType;
150    public final Type stringBuilderType;
151    public final Type cloneableType;
152    public final Type serializableType;
153    public final Type serializedLambdaType;
154    public final Type methodHandleType;
155    public final Type methodHandleLookupType;
156    public final Type methodTypeType;
157    public final Type nativeHeaderType;
158    public final Type throwableType;
159    public final Type errorType;
160    public final Type interruptedExceptionType;
161    public final Type illegalArgumentExceptionType;
162    public final Type exceptionType;
163    public final Type runtimeExceptionType;
164    public final Type classNotFoundExceptionType;
165    public final Type noClassDefFoundErrorType;
166    public final Type noSuchFieldErrorType;
167    public final Type assertionErrorType;
168    public final Type cloneNotSupportedExceptionType;
169    public final Type annotationType;
170    public final TypeSymbol enumSym;
171    public final Type listType;
172    public final Type collectionsType;
173    public final Type comparableType;
174    public final Type comparatorType;
175    public final Type arraysType;
176    public final Type iterableType;
177    public final Type iteratorType;
178    public final Type annotationTargetType;
179    public final Type overrideType;
180    public final Type retentionType;
181    public final Type deprecatedType;
182    public final Type suppressWarningsType;
183    public final Type supplierType;
184    public final Type inheritedType;
185    public final Type profileType;
186    public final Type proprietaryType;
187    public final Type systemType;
188    public final Type autoCloseableType;
189    public final Type trustMeType;
190    public final Type lambdaMetafactory;
191    public final Type stringConcatFactory;
192    public final Type repeatableType;
193    public final Type documentedType;
194    public final Type elementTypeType;
195    public final Type functionalInterfaceType;
196
197    /** The symbol representing the length field of an array.
198     */
199    public final VarSymbol lengthVar;
200
201    /** The symbol representing the final finalize method on enums */
202    public final MethodSymbol enumFinalFinalize;
203
204    /** The symbol representing the close method on TWR AutoCloseable type */
205    public final MethodSymbol autoCloseableClose;
206
207    /** The predefined type that belongs to a tag.
208     */
209    public final Type[] typeOfTag = new Type[TypeTag.getTypeTagCount()];
210
211    /** The name of the class that belongs to a basix type tag.
212     */
213    public final Name[] boxedName = new Name[TypeTag.getTypeTagCount()];
214
215    /** A hashtable containing the encountered top-level and member classes,
216     *  indexed by flat names. The table does not contain local classes.
217     *  It should be updated from the outside to reflect classes defined
218     *  by compiled source files.
219     */
220    public final Map<Name, ClassSymbol> classes = new HashMap<>();
221
222    /** A hashtable containing the encountered packages.
223     *  the table should be updated from outside to reflect packages defined
224     *  by compiled source files.
225     */
226    public final Map<Name, PackageSymbol> packages = new HashMap<>();
227
228    public void initType(Type type, ClassSymbol c) {
229        type.tsym = c;
230        typeOfTag[type.getTag().ordinal()] = type;
231    }
232
233    public void initType(Type type, String name) {
234        initType(
235            type,
236            new ClassSymbol(
237                PUBLIC, names.fromString(name), type, rootPackage));
238    }
239
240    public void initType(Type type, String name, String bname) {
241        initType(type, name);
242            boxedName[type.getTag().ordinal()] = names.fromString("java.lang." + bname);
243    }
244
245    /** The class symbol that owns all predefined symbols.
246     */
247    public final ClassSymbol predefClass;
248
249    /** Enter a class into symbol table.
250     *  @param s The name of the class.
251     */
252    private Type enterClass(String s) {
253        return enterClass(names.fromString(s)).type;
254    }
255
256    public void synthesizeEmptyInterfaceIfMissing(final Type type) {
257        final Completer completer = type.tsym.completer;
258        type.tsym.completer = new Completer() {
259            public void complete(Symbol sym) throws CompletionFailure {
260                try {
261                    completer.complete(sym);
262                } catch (CompletionFailure e) {
263                    sym.flags_field |= (PUBLIC | INTERFACE);
264                    ((ClassType) sym.type).supertype_field = objectType;
265                }
266            }
267
268            @Override
269            public boolean isTerminal() {
270                return completer.isTerminal();
271            }
272        };
273    }
274
275    public void synthesizeBoxTypeIfMissing(final Type type) {
276        ClassSymbol sym = enterClass(boxedName[type.getTag().ordinal()]);
277        final Completer completer = sym.completer;
278        sym.completer = new Completer() {
279            public void complete(Symbol sym) throws CompletionFailure {
280                try {
281                    completer.complete(sym);
282                } catch (CompletionFailure e) {
283                    sym.flags_field |= PUBLIC;
284                    ((ClassType) sym.type).supertype_field = objectType;
285                    MethodSymbol boxMethod =
286                        new MethodSymbol(PUBLIC | STATIC, names.valueOf,
287                                         new MethodType(List.of(type), sym.type,
288                                List.<Type>nil(), methodClass),
289                            sym);
290                    sym.members().enter(boxMethod);
291                    MethodSymbol unboxMethod =
292                        new MethodSymbol(PUBLIC,
293                            type.tsym.name.append(names.Value), // x.intValue()
294                            new MethodType(List.<Type>nil(), type,
295                                List.<Type>nil(), methodClass),
296                            sym);
297                    sym.members().enter(unboxMethod);
298                }
299            }
300
301            @Override
302            public boolean isTerminal() {
303                return completer.isTerminal();
304            }
305        };
306    }
307
308    // Enter a synthetic class that is used to mark classes in ct.sym.
309    // This class does not have a class file.
310    private Type enterSyntheticAnnotation(String name) {
311        ClassType type = (ClassType)enterClass(name);
312        ClassSymbol sym = (ClassSymbol)type.tsym;
313        sym.completer = Completer.NULL_COMPLETER;
314        sym.flags_field = PUBLIC|ACYCLIC|ANNOTATION|INTERFACE;
315        sym.erasure_field = type;
316        sym.members_field = WriteableScope.create(sym);
317        type.typarams_field = List.nil();
318        type.allparams_field = List.nil();
319        type.supertype_field = annotationType;
320        type.interfaces_field = List.nil();
321        return type;
322    }
323
324    /** Constructor; enters all predefined identifiers and operators
325     *  into symbol table.
326     */
327    protected Symtab(Context context) throws CompletionFailure {
328        context.put(symtabKey, this);
329
330        names = Names.instance(context);
331        target = Target.instance(context);
332
333        // Create the unknown type
334        unknownType = new UnknownType();
335
336        // create the basic builtin symbols
337        rootPackage = new PackageSymbol(names.empty, null);
338        packages.put(names.empty, rootPackage);
339        final JavacMessages messages = JavacMessages.instance(context);
340        unnamedPackage = new PackageSymbol(names.empty, rootPackage) {
341                public String toString() {
342                    return messages.getLocalizedString("compiler.misc.unnamed.package");
343                }
344            };
345        noSymbol = new TypeSymbol(NIL, 0, names.empty, Type.noType, rootPackage) {
346            @DefinedBy(Api.LANGUAGE_MODEL)
347            public <R, P> R accept(ElementVisitor<R, P> v, P p) {
348                return v.visitUnknown(this, p);
349            }
350        };
351
352        // create the error symbols
353        errSymbol = new ClassSymbol(PUBLIC|STATIC|ACYCLIC, names.any, null, rootPackage);
354        errType = new ErrorType(errSymbol, Type.noType);
355
356        unknownSymbol = new ClassSymbol(PUBLIC|STATIC|ACYCLIC, names.fromString("<any?>"), null, rootPackage);
357        unknownSymbol.members_field = new Scope.ErrorScope(unknownSymbol);
358        unknownSymbol.type = unknownType;
359
360        // initialize builtin types
361        initType(byteType, "byte", "Byte");
362        initType(shortType, "short", "Short");
363        initType(charType, "char", "Character");
364        initType(intType, "int", "Integer");
365        initType(longType, "long", "Long");
366        initType(floatType, "float", "Float");
367        initType(doubleType, "double", "Double");
368        initType(booleanType, "boolean", "Boolean");
369        initType(voidType, "void", "Void");
370        initType(botType, "<nulltype>");
371        initType(errType, errSymbol);
372        initType(unknownType, unknownSymbol);
373
374        // the builtin class of all arrays
375        arrayClass = new ClassSymbol(PUBLIC|ACYCLIC, names.Array, noSymbol);
376
377        // VGJ
378        boundClass = new ClassSymbol(PUBLIC|ACYCLIC, names.Bound, noSymbol);
379        boundClass.members_field = new Scope.ErrorScope(boundClass);
380
381        // the builtin class of all methods
382        methodClass = new ClassSymbol(PUBLIC|ACYCLIC, names.Method, noSymbol);
383        methodClass.members_field = new Scope.ErrorScope(boundClass);
384
385        // Create class to hold all predefined constants and operations.
386        predefClass = new ClassSymbol(PUBLIC|ACYCLIC, names.empty, rootPackage);
387        WriteableScope scope = WriteableScope.create(predefClass);
388        predefClass.members_field = scope;
389
390        // Get the initial completer for Symbols from the ClassFinder
391        initialCompleter = ClassFinder.instance(context).getCompleter();
392        rootPackage.completer = initialCompleter;
393        unnamedPackage.completer = initialCompleter;
394
395        // Enter symbols for basic types.
396        scope.enter(byteType.tsym);
397        scope.enter(shortType.tsym);
398        scope.enter(charType.tsym);
399        scope.enter(intType.tsym);
400        scope.enter(longType.tsym);
401        scope.enter(floatType.tsym);
402        scope.enter(doubleType.tsym);
403        scope.enter(booleanType.tsym);
404        scope.enter(errType.tsym);
405
406        // Enter symbol for the errSymbol
407        scope.enter(errSymbol);
408
409        classes.put(predefClass.fullname, predefClass);
410
411        // Enter predefined classes.
412        objectType = enterClass("java.lang.Object");
413        objectsType = enterClass("java.util.Objects");
414        classType = enterClass("java.lang.Class");
415        stringType = enterClass("java.lang.String");
416        stringBufferType = enterClass("java.lang.StringBuffer");
417        stringBuilderType = enterClass("java.lang.StringBuilder");
418        cloneableType = enterClass("java.lang.Cloneable");
419        throwableType = enterClass("java.lang.Throwable");
420        serializableType = enterClass("java.io.Serializable");
421        serializedLambdaType = enterClass("java.lang.invoke.SerializedLambda");
422        methodHandleType = enterClass("java.lang.invoke.MethodHandle");
423        methodHandleLookupType = enterClass("java.lang.invoke.MethodHandles$Lookup");
424        methodTypeType = enterClass("java.lang.invoke.MethodType");
425        errorType = enterClass("java.lang.Error");
426        illegalArgumentExceptionType = enterClass("java.lang.IllegalArgumentException");
427        interruptedExceptionType = enterClass("java.lang.InterruptedException");
428        exceptionType = enterClass("java.lang.Exception");
429        runtimeExceptionType = enterClass("java.lang.RuntimeException");
430        classNotFoundExceptionType = enterClass("java.lang.ClassNotFoundException");
431        noClassDefFoundErrorType = enterClass("java.lang.NoClassDefFoundError");
432        noSuchFieldErrorType = enterClass("java.lang.NoSuchFieldError");
433        assertionErrorType = enterClass("java.lang.AssertionError");
434        cloneNotSupportedExceptionType = enterClass("java.lang.CloneNotSupportedException");
435        annotationType = enterClass("java.lang.annotation.Annotation");
436        classLoaderType = enterClass("java.lang.ClassLoader");
437        enumSym = enterClass(names.java_lang_Enum);
438        enumFinalFinalize =
439            new MethodSymbol(PROTECTED|FINAL|HYPOTHETICAL,
440                             names.finalize,
441                             new MethodType(List.<Type>nil(), voidType,
442                                            List.<Type>nil(), methodClass),
443                             enumSym);
444        listType = enterClass("java.util.List");
445        collectionsType = enterClass("java.util.Collections");
446        comparableType = enterClass("java.lang.Comparable");
447        comparatorType = enterClass("java.util.Comparator");
448        arraysType = enterClass("java.util.Arrays");
449        iterableType = enterClass("java.lang.Iterable");
450        iteratorType = enterClass("java.util.Iterator");
451        annotationTargetType = enterClass("java.lang.annotation.Target");
452        overrideType = enterClass("java.lang.Override");
453        retentionType = enterClass("java.lang.annotation.Retention");
454        deprecatedType = enterClass("java.lang.Deprecated");
455        suppressWarningsType = enterClass("java.lang.SuppressWarnings");
456        supplierType = enterClass("java.util.function.Supplier");
457        inheritedType = enterClass("java.lang.annotation.Inherited");
458        repeatableType = enterClass("java.lang.annotation.Repeatable");
459        documentedType = enterClass("java.lang.annotation.Documented");
460        elementTypeType = enterClass("java.lang.annotation.ElementType");
461        systemType = enterClass("java.lang.System");
462        autoCloseableType = enterClass("java.lang.AutoCloseable");
463        autoCloseableClose = new MethodSymbol(PUBLIC,
464                             names.close,
465                             new MethodType(List.<Type>nil(), voidType,
466                                            List.of(exceptionType), methodClass),
467                             autoCloseableType.tsym);
468        trustMeType = enterClass("java.lang.SafeVarargs");
469        nativeHeaderType = enterClass("java.lang.annotation.Native");
470        lambdaMetafactory = enterClass("java.lang.invoke.LambdaMetafactory");
471        stringConcatFactory = enterClass("java.lang.invoke.StringConcatFactory");
472        functionalInterfaceType = enterClass("java.lang.FunctionalInterface");
473
474        synthesizeEmptyInterfaceIfMissing(autoCloseableType);
475        synthesizeEmptyInterfaceIfMissing(cloneableType);
476        synthesizeEmptyInterfaceIfMissing(serializableType);
477        synthesizeEmptyInterfaceIfMissing(lambdaMetafactory);
478        synthesizeEmptyInterfaceIfMissing(serializedLambdaType);
479        synthesizeEmptyInterfaceIfMissing(stringConcatFactory);
480        synthesizeBoxTypeIfMissing(doubleType);
481        synthesizeBoxTypeIfMissing(floatType);
482        synthesizeBoxTypeIfMissing(voidType);
483
484        // Enter a synthetic class that is used to mark internal
485        // proprietary classes in ct.sym.  This class does not have a
486        // class file.
487        proprietaryType = enterSyntheticAnnotation("sun.Proprietary+Annotation");
488
489        // Enter a synthetic class that is used to provide profile info for
490        // classes in ct.sym.  This class does not have a class file.
491        profileType = enterSyntheticAnnotation("jdk.Profile+Annotation");
492        MethodSymbol m = new MethodSymbol(PUBLIC | ABSTRACT, names.value, intType, profileType.tsym);
493        profileType.tsym.members().enter(m);
494
495        // Enter a class for arrays.
496        // The class implements java.lang.Cloneable and java.io.Serializable.
497        // It has a final length field and a clone method.
498        ClassType arrayClassType = (ClassType)arrayClass.type;
499        arrayClassType.supertype_field = objectType;
500        arrayClassType.interfaces_field = List.of(cloneableType, serializableType);
501        arrayClass.members_field = WriteableScope.create(arrayClass);
502        lengthVar = new VarSymbol(
503            PUBLIC | FINAL,
504            names.length,
505            intType,
506            arrayClass);
507        arrayClass.members().enter(lengthVar);
508        arrayCloneMethod = new MethodSymbol(
509            PUBLIC,
510            names.clone,
511            new MethodType(List.<Type>nil(), objectType,
512                           List.<Type>nil(), methodClass),
513            arrayClass);
514        arrayClass.members().enter(arrayCloneMethod);
515    }
516
517    /** Define a new class given its name and owner.
518     */
519    public ClassSymbol defineClass(Name name, Symbol owner) {
520        ClassSymbol c = new ClassSymbol(0, name, owner);
521        if (owner.kind == PCK)
522            Assert.checkNull(classes.get(c.flatname), c);
523        c.completer = initialCompleter;
524        return c;
525    }
526
527    /** Create a new toplevel or member class symbol with given name
528     *  and owner and enter in `classes' unless already there.
529     */
530    public ClassSymbol enterClass(Name name, TypeSymbol owner) {
531        Name flatname = TypeSymbol.formFlatName(name, owner);
532        ClassSymbol c = classes.get(flatname);
533        if (c == null) {
534            c = defineClass(name, owner);
535            classes.put(flatname, c);
536        } else if ((c.name != name || c.owner != owner) && owner.kind == TYP && c.owner.kind == PCK) {
537            // reassign fields of classes that might have been loaded with
538            // their flat names.
539            c.owner.members().remove(c);
540            c.name = name;
541            c.owner = owner;
542            c.fullname = ClassSymbol.formFullName(name, owner);
543        }
544        return c;
545    }
546
547    /**
548     * Creates a new toplevel class symbol with given flat name and
549     * given class (or source) file.
550     *
551     * @param flatName a fully qualified binary class name
552     * @param classFile the class file or compilation unit defining
553     * the class (may be {@code null})
554     * @return a newly created class symbol
555     * @throws AssertionError if the class symbol already exists
556     */
557    public ClassSymbol enterClass(Name flatName, JavaFileObject classFile) {
558        ClassSymbol cs = classes.get(flatName);
559        if (cs != null) {
560            String msg = Log.format("%s: completer = %s; class file = %s; source file = %s",
561                                    cs.fullname,
562                                    cs.completer,
563                                    cs.classfile,
564                                    cs.sourcefile);
565            throw new AssertionError(msg);
566        }
567        Name packageName = Convert.packagePart(flatName);
568        PackageSymbol owner = packageName.isEmpty()
569                                ? unnamedPackage
570                                : enterPackage(packageName);
571        cs = defineClass(Convert.shortName(flatName), owner);
572        cs.classfile = classFile;
573        classes.put(flatName, cs);
574        return cs;
575    }
576
577    /** Create a new member or toplevel class symbol with given flat name
578     *  and enter in `classes' unless already there.
579     */
580    public ClassSymbol enterClass(Name flatname) {
581        ClassSymbol c = classes.get(flatname);
582        if (c == null)
583            return enterClass(flatname, (JavaFileObject)null);
584        else
585            return c;
586    }
587
588    /** Check to see if a package exists, given its fully qualified name.
589     */
590    public boolean packageExists(Name fullname) {
591        return enterPackage(fullname).exists();
592    }
593
594    /** Make a package, given its fully qualified name.
595     */
596    public PackageSymbol enterPackage(Name fullname) {
597        PackageSymbol p = packages.get(fullname);
598        if (p == null) {
599            Assert.check(!fullname.isEmpty(), "rootPackage missing!");
600            p = new PackageSymbol(
601                Convert.shortName(fullname),
602                enterPackage(Convert.packagePart(fullname)));
603            p.completer = initialCompleter;
604            packages.put(fullname, p);
605        }
606        return p;
607    }
608
609    /** Make a package, given its unqualified name and enclosing package.
610     */
611    public PackageSymbol enterPackage(Name name, PackageSymbol owner) {
612        return enterPackage(TypeSymbol.formFullName(name, owner));
613    }
614}
615