aoqi@0: /* sadayapalam@2812: * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. aoqi@0: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. aoqi@0: * aoqi@0: * This code is free software; you can redistribute it and/or modify it aoqi@0: * under the terms of the GNU General Public License version 2 only, as aoqi@0: * published by the Free Software Foundation. Oracle designates this aoqi@0: * particular file as subject to the "Classpath" exception as provided aoqi@0: * by Oracle in the LICENSE file that accompanied this code. aoqi@0: * aoqi@0: * This code is distributed in the hope that it will be useful, but WITHOUT aoqi@0: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or aoqi@0: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License aoqi@0: * version 2 for more details (a copy is included in the LICENSE file that aoqi@0: * accompanied this code). aoqi@0: * aoqi@0: * You should have received a copy of the GNU General Public License version aoqi@0: * 2 along with this work; if not, write to the Free Software Foundation, aoqi@0: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. aoqi@0: * aoqi@0: * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA aoqi@0: * or visit www.oracle.com if you need additional information or have any aoqi@0: * questions. aoqi@0: */ aoqi@0: aoqi@0: package com.sun.tools.javac.code; aoqi@0: aoqi@0: import java.util.Iterator; aoqi@0: aoqi@0: import com.sun.tools.javac.util.*; aoqi@0: aoqi@0: /** A scope represents an area of visibility in a Java program. The aoqi@0: * Scope class is a container for symbols which provides aoqi@0: * efficient access to symbols given their names. Scopes are implemented aoqi@0: * as hash tables with "open addressing" and "double hashing". aoqi@0: * Scopes can be nested; the next field of a scope points aoqi@0: * to its next outer scope. Nested scopes can share their hash tables. aoqi@0: * aoqi@0: *

This is NOT part of any supported API. aoqi@0: * If you write code that depends on this, you do so at your own risk. aoqi@0: * This code and its internal interfaces are subject to change or aoqi@0: * deletion without notice. aoqi@0: */ aoqi@0: public class Scope { aoqi@0: aoqi@0: /** The number of scopes that share this scope's hash table. aoqi@0: */ aoqi@0: private int shared; aoqi@0: aoqi@0: /** Next enclosing scope (with whom this scope may share a hashtable) aoqi@0: */ aoqi@0: public Scope next; aoqi@0: aoqi@0: /** The scope's owner. aoqi@0: */ aoqi@0: public Symbol owner; aoqi@0: aoqi@0: /** A hash table for the scope's entries. aoqi@0: */ aoqi@0: Entry[] table; aoqi@0: aoqi@0: /** Mask for hash codes, always equal to (table.length - 1). aoqi@0: */ aoqi@0: int hashMask; aoqi@0: aoqi@0: /** A linear list that also contains all entries in aoqi@0: * reverse order of appearance (i.e later entries are pushed on top). aoqi@0: */ aoqi@0: public Entry elems; aoqi@0: aoqi@0: /** The number of elements in this scope. aoqi@0: * This includes deleted elements, whose value is the sentinel. aoqi@0: */ aoqi@0: int nelems = 0; aoqi@0: aoqi@0: /** A list of scopes to be notified if items are to be removed from this scope. aoqi@0: */ aoqi@0: List listeners = List.nil(); aoqi@0: aoqi@0: /** Use as a "not-found" result for lookup. aoqi@0: * Also used to mark deleted entries in the table. aoqi@0: */ aoqi@0: private static final Entry sentinel = new Entry(null, null, null, null); aoqi@0: aoqi@0: /** The hash table's initial size. aoqi@0: */ aoqi@0: private static final int INITIAL_SIZE = 0x10; aoqi@0: aoqi@0: /** A value for the empty scope. aoqi@0: */ aoqi@0: public static final Scope emptyScope = new Scope(null, null, new Entry[]{}); aoqi@0: aoqi@0: /** Construct a new scope, within scope next, with given owner, using aoqi@0: * given table. The table's length must be an exponent of 2. aoqi@0: */ aoqi@0: private Scope(Scope next, Symbol owner, Entry[] table) { aoqi@0: this.next = next; aoqi@0: Assert.check(emptyScope == null || owner != null); aoqi@0: this.owner = owner; aoqi@0: this.table = table; aoqi@0: this.hashMask = table.length - 1; aoqi@0: } aoqi@0: aoqi@0: /** Convenience constructor used for dup and dupUnshared. */ aoqi@0: private Scope(Scope next, Symbol owner, Entry[] table, int nelems) { aoqi@0: this(next, owner, table); aoqi@0: this.nelems = nelems; aoqi@0: } aoqi@0: aoqi@0: /** Construct a new scope, within scope next, with given owner, aoqi@0: * using a fresh table of length INITIAL_SIZE. aoqi@0: */ aoqi@0: public Scope(Symbol owner) { aoqi@0: this(null, owner, new Entry[INITIAL_SIZE]); aoqi@0: } aoqi@0: aoqi@0: /** Construct a fresh scope within this scope, with same owner, aoqi@0: * which shares its table with the outer scope. Used in connection with aoqi@0: * method leave if scope access is stack-like in order to avoid allocation aoqi@0: * of fresh tables. aoqi@0: */ aoqi@0: public Scope dup() { aoqi@0: return dup(this.owner); aoqi@0: } aoqi@0: aoqi@0: /** Construct a fresh scope within this scope, with new owner, aoqi@0: * which shares its table with the outer scope. Used in connection with aoqi@0: * method leave if scope access is stack-like in order to avoid allocation aoqi@0: * of fresh tables. aoqi@0: */ aoqi@0: public Scope dup(Symbol newOwner) { aoqi@0: Scope result = new Scope(this, newOwner, this.table, this.nelems); aoqi@0: shared++; aoqi@0: // System.out.println("====> duping scope " + this.hashCode() + " owned by " + newOwner + " to " + result.hashCode()); aoqi@0: // new Error().printStackTrace(System.out); aoqi@0: return result; aoqi@0: } aoqi@0: aoqi@0: /** Construct a fresh scope within this scope, with same owner, aoqi@0: * with a new hash table, whose contents initially are those of aoqi@0: * the table of its outer scope. aoqi@0: */ aoqi@0: public Scope dupUnshared() { aoqi@0: return new Scope(this, this.owner, this.table.clone(), this.nelems); aoqi@0: } aoqi@0: aoqi@0: /** Remove all entries of this scope from its table, if shared aoqi@0: * with next. aoqi@0: */ aoqi@0: public Scope leave() { aoqi@0: Assert.check(shared == 0); aoqi@0: if (table != next.table) return next; aoqi@0: while (elems != null) { aoqi@0: int hash = getIndex(elems.sym.name); aoqi@0: Entry e = table[hash]; aoqi@0: Assert.check(e == elems, elems.sym); aoqi@0: table[hash] = elems.shadowed; aoqi@0: elems = elems.sibling; aoqi@0: } aoqi@0: Assert.check(next.shared > 0); aoqi@0: next.shared--; aoqi@0: next.nelems = nelems; aoqi@0: // System.out.println("====> leaving scope " + this.hashCode() + " owned by " + this.owner + " to " + next.hashCode()); aoqi@0: // new Error().printStackTrace(System.out); aoqi@0: return next; aoqi@0: } aoqi@0: aoqi@0: /** Double size of hash table. aoqi@0: */ aoqi@0: private void dble() { aoqi@0: Assert.check(shared == 0); aoqi@0: Entry[] oldtable = table; aoqi@0: Entry[] newtable = new Entry[oldtable.length * 2]; aoqi@0: for (Scope s = this; s != null; s = s.next) { aoqi@0: if (s.table == oldtable) { aoqi@0: Assert.check(s == this || s.shared != 0); aoqi@0: s.table = newtable; aoqi@0: s.hashMask = newtable.length - 1; aoqi@0: } aoqi@0: } aoqi@0: int n = 0; aoqi@0: for (int i = oldtable.length; --i >= 0; ) { aoqi@0: Entry e = oldtable[i]; aoqi@0: if (e != null && e != sentinel) { aoqi@0: table[getIndex(e.sym.name)] = e; aoqi@0: n++; aoqi@0: } aoqi@0: } aoqi@0: // We don't need to update nelems for shared inherited scopes, aoqi@0: // since that gets handled by leave(). aoqi@0: nelems = n; aoqi@0: } aoqi@0: aoqi@0: /** Enter symbol sym in this scope. aoqi@0: */ aoqi@0: public void enter(Symbol sym) { aoqi@0: Assert.check(shared == 0); aoqi@0: enter(sym, this); aoqi@0: } aoqi@0: aoqi@0: public void enter(Symbol sym, Scope s) { aoqi@0: enter(sym, s, s, false); aoqi@0: } aoqi@0: aoqi@0: /** aoqi@0: * Enter symbol sym in this scope, but mark that it comes from aoqi@0: * given scope `s' accessed through `origin'. The last two aoqi@0: * arguments are only used in import scopes. aoqi@0: */ aoqi@0: public void enter(Symbol sym, Scope s, Scope origin, boolean staticallyImported) { aoqi@0: Assert.check(shared == 0); aoqi@0: if (nelems * 3 >= hashMask * 2) aoqi@0: dble(); aoqi@0: int hash = getIndex(sym.name); aoqi@0: Entry old = table[hash]; aoqi@0: if (old == null) { aoqi@0: old = sentinel; aoqi@0: nelems++; aoqi@0: } aoqi@0: Entry e = makeEntry(sym, old, elems, s, origin, staticallyImported); aoqi@0: table[hash] = e; aoqi@0: elems = e; aoqi@0: aoqi@0: //notify listeners aoqi@0: for (List l = listeners; l.nonEmpty(); l = l.tail) { aoqi@0: l.head.symbolAdded(sym, this); aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: Entry makeEntry(Symbol sym, Entry shadowed, Entry sibling, Scope scope, Scope origin, boolean staticallyImported) { aoqi@0: return new Entry(sym, shadowed, sibling, scope); aoqi@0: } aoqi@0: aoqi@0: aoqi@0: public interface ScopeListener { aoqi@0: public void symbolAdded(Symbol sym, Scope s); aoqi@0: public void symbolRemoved(Symbol sym, Scope s); aoqi@0: } aoqi@0: aoqi@0: public void addScopeListener(ScopeListener sl) { aoqi@0: listeners = listeners.prepend(sl); aoqi@0: } aoqi@0: sadayapalam@2812: /** Remove symbol from this scope. aoqi@0: */ sadayapalam@2812: public void remove(final Symbol sym) { aoqi@0: Assert.check(shared == 0); sadayapalam@2812: Entry e = lookup(sym.name, new Filter() { sadayapalam@2812: @Override sadayapalam@2812: public boolean accepts(Symbol candidate) { sadayapalam@2812: return candidate == sym; sadayapalam@2812: } sadayapalam@2812: }); aoqi@0: if (e.scope == null) return; aoqi@0: aoqi@0: // remove e from table and shadowed list; aoqi@0: int i = getIndex(sym.name); aoqi@0: Entry te = table[i]; aoqi@0: if (te == e) aoqi@0: table[i] = e.shadowed; aoqi@0: else while (true) { aoqi@0: if (te.shadowed == e) { aoqi@0: te.shadowed = e.shadowed; aoqi@0: break; aoqi@0: } aoqi@0: te = te.shadowed; aoqi@0: } aoqi@0: aoqi@0: // remove e from elems and sibling list aoqi@0: te = elems; aoqi@0: if (te == e) aoqi@0: elems = e.sibling; aoqi@0: else while (true) { aoqi@0: if (te.sibling == e) { aoqi@0: te.sibling = e.sibling; aoqi@0: break; aoqi@0: } aoqi@0: te = te.sibling; aoqi@0: } aoqi@0: aoqi@0: //notify listeners aoqi@0: for (List l = listeners; l.nonEmpty(); l = l.tail) { aoqi@0: l.head.symbolRemoved(sym, this); aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: /** Enter symbol sym in this scope if not already there. aoqi@0: */ aoqi@0: public void enterIfAbsent(Symbol sym) { aoqi@0: Assert.check(shared == 0); aoqi@0: Entry e = lookup(sym.name); aoqi@0: while (e.scope == this && e.sym.kind != sym.kind) e = e.next(); aoqi@0: if (e.scope != this) enter(sym); aoqi@0: } aoqi@0: aoqi@0: /** Given a class, is there already a class with same fully aoqi@0: * qualified name in this (import) scope? aoqi@0: */ aoqi@0: public boolean includes(Symbol c) { aoqi@0: for (Scope.Entry e = lookup(c.name); aoqi@0: e.scope == this; aoqi@0: e = e.next()) { aoqi@0: if (e.sym == c) return true; aoqi@0: } aoqi@0: return false; aoqi@0: } aoqi@0: aoqi@0: static final Filter noFilter = new Filter() { aoqi@0: public boolean accepts(Symbol s) { aoqi@0: return true; aoqi@0: } aoqi@0: }; aoqi@0: aoqi@0: /** Return the entry associated with given name, starting in aoqi@0: * this scope and proceeding outwards. If no entry was found, aoqi@0: * return the sentinel, which is characterized by having a null in aoqi@0: * both its scope and sym fields, whereas both fields are non-null aoqi@0: * for regular entries. aoqi@0: */ aoqi@0: public Entry lookup(Name name) { aoqi@0: return lookup(name, noFilter); aoqi@0: } aoqi@0: aoqi@0: public Entry lookup(Name name, Filter sf) { aoqi@0: Entry e = table[getIndex(name)]; aoqi@0: if (e == null || e == sentinel) aoqi@0: return sentinel; aoqi@0: while (e.scope != null && (e.sym.name != name || !sf.accepts(e.sym))) aoqi@0: e = e.shadowed; aoqi@0: return e; aoqi@0: } aoqi@0: aoqi@0: /*void dump (java.io.PrintStream out) { aoqi@0: out.println(this); aoqi@0: for (int l=0; l < table.length; l++) { aoqi@0: Entry le = table[l]; aoqi@0: out.print("#"+l+": "); aoqi@0: if (le==sentinel) out.println("sentinel"); aoqi@0: else if(le == null) out.println("null"); aoqi@0: else out.println(""+le+" s:"+le.sym); aoqi@0: } aoqi@0: }*/ aoqi@0: aoqi@0: /** Look for slot in the table. aoqi@0: * We use open addressing with double hashing. aoqi@0: */ aoqi@0: int getIndex (Name name) { aoqi@0: int h = name.hashCode(); aoqi@0: int i = h & hashMask; aoqi@0: // The expression below is always odd, so it is guaranteed aoqi@0: // to be mutually prime with table.length, a power of 2. aoqi@0: int x = hashMask - ((h + (h >> 16)) << 1); aoqi@0: int d = -1; // Index of a deleted item. aoqi@0: for (;;) { aoqi@0: Entry e = table[i]; aoqi@0: if (e == null) aoqi@0: return d >= 0 ? d : i; aoqi@0: if (e == sentinel) { aoqi@0: // We have to keep searching even if we see a deleted item. aoqi@0: // However, remember the index in case we fail to find the name. aoqi@0: if (d < 0) aoqi@0: d = i; aoqi@0: } else if (e.sym.name == name) aoqi@0: return i; aoqi@0: i = (i + x) & hashMask; aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: public boolean anyMatch(Filter sf) { aoqi@0: return getElements(sf).iterator().hasNext(); aoqi@0: } aoqi@0: aoqi@0: public Iterable getElements() { aoqi@0: return getElements(noFilter); aoqi@0: } aoqi@0: aoqi@0: public Iterable getElements(final Filter sf) { aoqi@0: return new Iterable() { aoqi@0: public Iterator iterator() { aoqi@0: return new Iterator() { aoqi@0: private Scope currScope = Scope.this; aoqi@0: private Scope.Entry currEntry = elems; aoqi@0: { aoqi@0: update(); aoqi@0: } aoqi@0: aoqi@0: public boolean hasNext() { aoqi@0: return currEntry != null; aoqi@0: } aoqi@0: aoqi@0: public Symbol next() { aoqi@0: Symbol sym = (currEntry == null ? null : currEntry.sym); aoqi@0: if (currEntry != null) { aoqi@0: currEntry = currEntry.sibling; aoqi@0: } aoqi@0: update(); aoqi@0: return sym; aoqi@0: } aoqi@0: aoqi@0: public void remove() { aoqi@0: throw new UnsupportedOperationException(); aoqi@0: } aoqi@0: aoqi@0: private void update() { aoqi@0: skipToNextMatchingEntry(); aoqi@0: while (currEntry == null && currScope.next != null) { aoqi@0: currScope = currScope.next; aoqi@0: currEntry = currScope.elems; aoqi@0: skipToNextMatchingEntry(); aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: void skipToNextMatchingEntry() { aoqi@0: while (currEntry != null && !sf.accepts(currEntry.sym)) { aoqi@0: currEntry = currEntry.sibling; aoqi@0: } aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: aoqi@0: public Iterable getElementsByName(Name name) { aoqi@0: return getElementsByName(name, noFilter); aoqi@0: } aoqi@0: aoqi@0: public Iterable getElementsByName(final Name name, final Filter sf) { aoqi@0: return new Iterable() { aoqi@0: public Iterator iterator() { aoqi@0: return new Iterator() { aoqi@0: Scope.Entry currentEntry = lookup(name, sf); aoqi@0: aoqi@0: public boolean hasNext() { aoqi@0: return currentEntry.scope != null; aoqi@0: } aoqi@0: public Symbol next() { aoqi@0: Scope.Entry prevEntry = currentEntry; aoqi@0: currentEntry = currentEntry.next(sf); aoqi@0: return prevEntry.sym; aoqi@0: } aoqi@0: public void remove() { aoqi@0: throw new UnsupportedOperationException(); aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: aoqi@0: public String toString() { aoqi@0: StringBuilder result = new StringBuilder(); aoqi@0: result.append("Scope["); aoqi@0: for (Scope s = this; s != null ; s = s.next) { aoqi@0: if (s != this) result.append(" | "); aoqi@0: for (Entry e = s.elems; e != null; e = e.sibling) { aoqi@0: if (e != s.elems) result.append(", "); aoqi@0: result.append(e.sym); aoqi@0: } aoqi@0: } aoqi@0: result.append("]"); aoqi@0: return result.toString(); aoqi@0: } aoqi@0: aoqi@0: /** A class for scope entries. aoqi@0: */ aoqi@0: public static class Entry { aoqi@0: aoqi@0: /** The referenced symbol. aoqi@0: * sym == null iff this == sentinel aoqi@0: */ aoqi@0: public Symbol sym; aoqi@0: aoqi@0: /** An entry with the same hash code, or sentinel. aoqi@0: */ aoqi@0: private Entry shadowed; aoqi@0: aoqi@0: /** Next entry in same scope. aoqi@0: */ aoqi@0: public Entry sibling; aoqi@0: aoqi@0: /** The entry's scope. aoqi@0: * scope == null iff this == sentinel aoqi@0: * for an entry in an import scope, this is the scope aoqi@0: * where the entry came from (i.e. was imported from). aoqi@0: */ aoqi@0: public Scope scope; aoqi@0: aoqi@0: public Entry(Symbol sym, Entry shadowed, Entry sibling, Scope scope) { aoqi@0: this.sym = sym; aoqi@0: this.shadowed = shadowed; aoqi@0: this.sibling = sibling; aoqi@0: this.scope = scope; aoqi@0: } aoqi@0: aoqi@0: /** Return next entry with the same name as this entry, proceeding aoqi@0: * outwards if not found in this scope. aoqi@0: */ aoqi@0: public Entry next() { aoqi@0: return shadowed; aoqi@0: } aoqi@0: aoqi@0: public Entry next(Filter sf) { aoqi@0: if (shadowed.sym == null || sf.accepts(shadowed.sym)) return shadowed; aoqi@0: else return shadowed.next(sf); aoqi@0: } aoqi@0: aoqi@0: public boolean isStaticallyImported() { aoqi@0: return false; aoqi@0: } aoqi@0: aoqi@0: public Scope getOrigin() { aoqi@0: // The origin is only recorded for import scopes. For all aoqi@0: // other scope entries, the "enclosing" type is available aoqi@0: // from other sources. See Attr.visitSelect and aoqi@0: // Attr.visitIdent. Rather than throwing an assertion aoqi@0: // error, we return scope which will be the same as origin aoqi@0: // in many cases. aoqi@0: return scope; aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: public static class ImportScope extends Scope { aoqi@0: aoqi@0: public ImportScope(Symbol owner) { aoqi@0: super(owner); aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: Entry makeEntry(Symbol sym, Entry shadowed, Entry sibling, Scope scope, aoqi@0: final Scope origin, final boolean staticallyImported) { aoqi@0: return new Entry(sym, shadowed, sibling, scope) { aoqi@0: @Override aoqi@0: public Scope getOrigin() { aoqi@0: return origin; aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public boolean isStaticallyImported() { aoqi@0: return staticallyImported; aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: public static class StarImportScope extends ImportScope implements ScopeListener { aoqi@0: aoqi@0: public StarImportScope(Symbol owner) { aoqi@0: super(owner); aoqi@0: } aoqi@0: aoqi@0: public void importAll (Scope fromScope) { aoqi@0: for (Scope.Entry e = fromScope.elems; e != null; e = e.sibling) { aoqi@0: if (e.sym.kind == Kinds.TYP && !includes(e.sym)) aoqi@0: enter(e.sym, fromScope); aoqi@0: } aoqi@0: // Register to be notified when imported items are removed aoqi@0: fromScope.addScopeListener(this); aoqi@0: } aoqi@0: aoqi@0: public void symbolRemoved(Symbol sym, Scope s) { aoqi@0: remove(sym); aoqi@0: } aoqi@0: public void symbolAdded(Symbol sym, Scope s) { } aoqi@0: } aoqi@0: aoqi@0: /** An empty scope, into which you can't place anything. Used for aoqi@0: * the scope for a variable initializer. aoqi@0: */ aoqi@0: public static class DelegatedScope extends Scope { aoqi@0: Scope delegatee; aoqi@0: public static final Entry[] emptyTable = new Entry[0]; aoqi@0: aoqi@0: public DelegatedScope(Scope outer) { aoqi@0: super(outer, outer.owner, emptyTable); aoqi@0: delegatee = outer; aoqi@0: } aoqi@0: public Scope dup() { aoqi@0: return new DelegatedScope(next); aoqi@0: } aoqi@0: public Scope dupUnshared() { aoqi@0: return new DelegatedScope(next); aoqi@0: } aoqi@0: public Scope leave() { aoqi@0: return next; aoqi@0: } aoqi@0: public void enter(Symbol sym) { aoqi@0: // only anonymous classes could be put here aoqi@0: } aoqi@0: public void enter(Symbol sym, Scope s) { aoqi@0: // only anonymous classes could be put here aoqi@0: } aoqi@0: public void remove(Symbol sym) { aoqi@0: throw new AssertionError(sym); aoqi@0: } aoqi@0: public Entry lookup(Name name) { aoqi@0: return delegatee.lookup(name); aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: /** A class scope adds capabilities to keep track of changes in related aoqi@0: * class scopes - this allows client to realize whether a class scope aoqi@0: * has changed, either directly (because a new member has been added/removed aoqi@0: * to this scope) or indirectly (i.e. because a new member has been aoqi@0: * added/removed into a supertype scope) aoqi@0: */ aoqi@0: public static class CompoundScope extends Scope implements ScopeListener { aoqi@0: aoqi@0: public static final Entry[] emptyTable = new Entry[0]; aoqi@0: aoqi@0: private List subScopes = List.nil(); aoqi@0: private int mark = 0; aoqi@0: aoqi@0: public CompoundScope(Symbol owner) { aoqi@0: super(null, owner, emptyTable); aoqi@0: } aoqi@0: aoqi@0: public void addSubScope(Scope that) { aoqi@0: if (that != null) { aoqi@0: subScopes = subScopes.prepend(that); aoqi@0: that.addScopeListener(this); aoqi@0: mark++; aoqi@0: for (ScopeListener sl : listeners) { aoqi@0: sl.symbolAdded(null, this); //propagate upwards in case of nested CompoundScopes aoqi@0: } aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: public void symbolAdded(Symbol sym, Scope s) { aoqi@0: mark++; aoqi@0: for (ScopeListener sl : listeners) { aoqi@0: sl.symbolAdded(sym, s); aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: public void symbolRemoved(Symbol sym, Scope s) { aoqi@0: mark++; aoqi@0: for (ScopeListener sl : listeners) { aoqi@0: sl.symbolRemoved(sym, s); aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: public int getMark() { aoqi@0: return mark; aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public String toString() { aoqi@0: StringBuilder buf = new StringBuilder(); aoqi@0: buf.append("CompoundScope{"); aoqi@0: String sep = ""; aoqi@0: for (Scope s : subScopes) { aoqi@0: buf.append(sep); aoqi@0: buf.append(s); aoqi@0: sep = ","; aoqi@0: } aoqi@0: buf.append("}"); aoqi@0: return buf.toString(); aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public Iterable getElements(final Filter sf) { aoqi@0: return new Iterable() { aoqi@0: public Iterator iterator() { aoqi@0: return new CompoundScopeIterator(subScopes) { aoqi@0: Iterator nextIterator(Scope s) { aoqi@0: return s.getElements(sf).iterator(); aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public Iterable getElementsByName(final Name name, final Filter sf) { aoqi@0: return new Iterable() { aoqi@0: public Iterator iterator() { aoqi@0: return new CompoundScopeIterator(subScopes) { aoqi@0: Iterator nextIterator(Scope s) { aoqi@0: return s.getElementsByName(name, sf).iterator(); aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: }; aoqi@0: } aoqi@0: aoqi@0: abstract class CompoundScopeIterator implements Iterator { aoqi@0: aoqi@0: private Iterator currentIterator; aoqi@0: private List scopesToScan; aoqi@0: aoqi@0: public CompoundScopeIterator(List scopesToScan) { aoqi@0: this.scopesToScan = scopesToScan; aoqi@0: update(); aoqi@0: } aoqi@0: aoqi@0: abstract Iterator nextIterator(Scope s); aoqi@0: aoqi@0: public boolean hasNext() { aoqi@0: return currentIterator != null; aoqi@0: } aoqi@0: aoqi@0: public Symbol next() { aoqi@0: Symbol sym = currentIterator.next(); aoqi@0: if (!currentIterator.hasNext()) { aoqi@0: update(); aoqi@0: } aoqi@0: return sym; aoqi@0: } aoqi@0: aoqi@0: public void remove() { aoqi@0: throw new UnsupportedOperationException(); aoqi@0: } aoqi@0: aoqi@0: private void update() { aoqi@0: while (scopesToScan.nonEmpty()) { aoqi@0: currentIterator = nextIterator(scopesToScan.head); aoqi@0: scopesToScan = scopesToScan.tail; aoqi@0: if (currentIterator.hasNext()) return; aoqi@0: } aoqi@0: currentIterator = null; aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public Entry lookup(Name name, Filter sf) { aoqi@0: throw new UnsupportedOperationException(); aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public Scope dup(Symbol newOwner) { aoqi@0: throw new UnsupportedOperationException(); aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public void enter(Symbol sym, Scope s, Scope origin, boolean staticallyImported) { aoqi@0: throw new UnsupportedOperationException(); aoqi@0: } aoqi@0: aoqi@0: @Override aoqi@0: public void remove(Symbol sym) { aoqi@0: throw new UnsupportedOperationException(); aoqi@0: } aoqi@0: } aoqi@0: aoqi@0: /** An error scope, for which the owner should be an error symbol. */ aoqi@0: public static class ErrorScope extends Scope { aoqi@0: ErrorScope(Scope next, Symbol errSymbol, Entry[] table) { aoqi@0: super(next, /*owner=*/errSymbol, table); aoqi@0: } aoqi@0: public ErrorScope(Symbol errSymbol) { aoqi@0: super(errSymbol); aoqi@0: } aoqi@0: public Scope dup() { aoqi@0: return new ErrorScope(this, owner, table); aoqi@0: } aoqi@0: public Scope dupUnshared() { aoqi@0: return new ErrorScope(this, owner, table.clone()); aoqi@0: } aoqi@0: public Entry lookup(Name name) { aoqi@0: Entry e = super.lookup(name); aoqi@0: if (e.scope == null) aoqi@0: return new Entry(owner, null, null, null); aoqi@0: else aoqi@0: return e; aoqi@0: } aoqi@0: } aoqi@0: }