/*
* Copyright (c) 1999, 2016, 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
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*/
package com.sun.tools.javac.code;
import com.sun.tools.javac.code.Kinds.Kind;
import java.lang.ref.WeakReference;
import java.util.*;
import java.util.function.BiConsumer;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;
import com.sun.tools.javac.code.Symbol.CompletionFailure;
import com.sun.tools.javac.code.Symbol.TypeSymbol;
import com.sun.tools.javac.tree.JCTree.JCImport;
import com.sun.tools.javac.util.*;
import com.sun.tools.javac.util.List;
import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
import static com.sun.tools.javac.code.Scope.LookupKind.RECURSIVE;
/** A scope represents an area of visibility in a Java program. The
* Scope class is a container for symbols which provides
* efficient access to symbols given their names. Scopes are implemented
* as hash tables with "open addressing" and "double hashing".
* Scopes can be nested. Nested scopes can share their hash tables.
*
* <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>
*/
public abstract class Scope {
/** The scope's owner.
*/
public final Symbol owner;
protected Scope(Symbol owner) {
this.owner = owner;
}
/**Returns all Symbols in this Scope. Symbols from outward Scopes are included.
*/
public final Iterable<Symbol> getSymbols() {
return getSymbols(noFilter);
}
/**Returns Symbols that match the given filter. Symbols from outward Scopes are included.
*/
public final Iterable<Symbol> getSymbols(Filter<Symbol> sf) {
return getSymbols(sf, RECURSIVE);
}
/**Returns all Symbols in this Scope. Symbols from outward Scopes are included
* iff lookupKind == RECURSIVE.
*/
public final Iterable<Symbol> getSymbols(LookupKind lookupKind) {
return getSymbols(noFilter, lookupKind);
}
/**Returns Symbols that match the given filter. Symbols from outward Scopes are included
* iff lookupKind == RECURSIVE.
*/
public abstract Iterable<Symbol> getSymbols(Filter<Symbol> sf, LookupKind lookupKind);
/**Returns Symbols with the given name. Symbols from outward Scopes are included.
*/
public final Iterable<Symbol> getSymbolsByName(Name name) {
return getSymbolsByName(name, RECURSIVE);
}
/**Returns Symbols with the given name that match the given filter.
* Symbols from outward Scopes are included.
*/
public final Iterable<Symbol> getSymbolsByName(final Name name, final Filter<Symbol> sf) {
return getSymbolsByName(name, sf, RECURSIVE);
}
/**Returns Symbols with the given name. Symbols from outward Scopes are included
* iff lookupKind == RECURSIVE.
*/
public final Iterable<Symbol> getSymbolsByName(Name name, LookupKind lookupKind) {
return getSymbolsByName(name, noFilter, lookupKind);
}
/**Returns Symbols with the given name that match the given filter.
* Symbols from outward Scopes are included iff lookupKind == RECURSIVE.
*/
public abstract Iterable<Symbol> getSymbolsByName(final Name name, final Filter<Symbol> sf,
final LookupKind lookupKind);
/** Return the first Symbol from this or outward scopes with the given name.
* Returns null if none.
*/
public final Symbol findFirst(Name name) {
return findFirst(name, noFilter);
}
/** Return the first Symbol from this or outward scopes with the given name that matches the
* given filter. Returns null if none.
*/
public Symbol findFirst(Name name, Filter<Symbol> sf) {
Iterator<Symbol> it = getSymbolsByName(name, sf).iterator();
return it.hasNext() ? it.next() : null;
}
/** Returns true iff there are is at least one Symbol in this scope matching the given filter.
* Does not inspect outward scopes.
*/
public boolean anyMatch(Filter<Symbol> filter) {
return getSymbols(filter, NON_RECURSIVE).iterator().hasNext();
}
/** Returns true iff the given Symbol is in this scope or any outward scope.
*/
public boolean includes(final Symbol sym) {
return includes(sym, RECURSIVE);
}
/** Returns true iff the given Symbol is in this scope, optionally checking outward scopes.
*/
public boolean includes(final Symbol sym, LookupKind lookupKind) {
return getSymbolsByName(sym.name, new Filter<Symbol>() {
@Override
public boolean accepts(Symbol t) {
return t == sym;
}
}, lookupKind).iterator().hasNext();
}
/** Returns true iff this scope does not contain any Symbol. Does not inspect outward scopes.
*/
public boolean isEmpty() {
return !getSymbols(NON_RECURSIVE).iterator().hasNext();
}
/** Returns the Scope from which the givins Symbol originates in this scope.
*/
public abstract Scope getOrigin(Symbol byName);
/** Returns true iff the given Symbol is part of this scope due to a static import.
*/
public abstract boolean isStaticallyImported(Symbol byName);
private static final Filter<Symbol> noFilter = null;
/** A list of scopes to be notified if items are to be removed from this scope.
*/
ScopeListenerList listeners = new ScopeListenerList();
public interface ScopeListener {
void symbolAdded(Symbol sym, Scope s);
void symbolRemoved(Symbol sym, Scope s);
}
/**
* A list of scope listeners; listeners are stored in weak references, to avoid memory leaks.
* When the listener list is scanned (upon notification), elements corresponding to GC-ed
* listeners are removed so that the listener list size is kept in check.
*/
public static class ScopeListenerList {
List<WeakReference<ScopeListener>> listeners = List.nil();
void add(ScopeListener sl) {
listeners = listeners.prepend(new WeakReference<>(sl));
}
void symbolAdded(Symbol sym, Scope scope) {
walkReferences(sym, scope, false);
}
void symbolRemoved(Symbol sym, Scope scope) {
walkReferences(sym, scope, true);
}
private void walkReferences(Symbol sym, Scope scope, boolean isRemove) {
ListBuffer<WeakReference<ScopeListener>> newListeners = new ListBuffer<>();
for (WeakReference<ScopeListener> wsl : listeners) {
ScopeListener sl = wsl.get();
if (sl != null) {
if (isRemove) {
sl.symbolRemoved(sym, scope);
} else {
sl.symbolAdded(sym, scope);
}
newListeners.add(wsl);
}
}
listeners = newListeners.toList();
}
}
public enum LookupKind {
RECURSIVE,
NON_RECURSIVE;
}
/**A scope into which Symbols can be added.*/
public abstract static class WriteableScope extends Scope {
public WriteableScope(Symbol owner) {
super(owner);
}
/** Enter the given Symbol into this scope.
*/
public abstract void enter(Symbol c);
/** Enter symbol sym in this scope if not already there.
*/
public abstract void enterIfAbsent(Symbol c);
public abstract void remove(Symbol c);
/** Construct a fresh scope within this scope, with same owner. The new scope may
* shares internal structures with the this scope. Used in connection with
* method leave if scope access is stack-like in order to avoid allocation
* of fresh tables.
*/
public final WriteableScope dup() {
return dup(this.owner);
}
/** Construct a fresh scope within this scope, with new owner. The new scope may
* shares internal structures with the this scope. Used in connection with
* method leave if scope access is stack-like in order to avoid allocation
* of fresh tables.
*/
public abstract WriteableScope dup(Symbol newOwner);
/** Must be called on dup-ed scopes to be able to work with the outward scope again.
*/
public abstract WriteableScope leave();
/** Construct a fresh scope within this scope, with same owner. The new scope
* will not share internal structures with this scope.
*/
public final WriteableScope dupUnshared() {
return dupUnshared(owner);
}
/** Construct a fresh scope within this scope, with new owner. The new scope
* will not share internal structures with this scope.
*/
public abstract WriteableScope dupUnshared(Symbol newOwner);
/** Create a new WriteableScope.
*/
public static WriteableScope create(Symbol owner) {
return new ScopeImpl(owner);
}
}
private static class ScopeImpl extends WriteableScope {
/** The number of scopes that share this scope's hash table.
*/
private int shared;
/** Next enclosing scope (with whom this scope may share a hashtable)
*/
public ScopeImpl next;
/** A hash table for the scope's entries.
*/
Entry[] table;
/** Mask for hash codes, always equal to (table.length - 1).
*/
int hashMask;
/** A linear list that also contains all entries in
* reverse order of appearance (i.e later entries are pushed on top).
*/
public Entry elems;
/** The number of elements in this scope.
* This includes deleted elements, whose value is the sentinel.
*/
int nelems = 0;
int removeCount = 0;
/** Use as a "not-found" result for lookup.
* Also used to mark deleted entries in the table.
*/
private static final Entry sentinel = new Entry(null, null, null, null);
/** The hash table's initial size.
*/
private static final int INITIAL_SIZE = 0x10;
/** Construct a new scope, within scope next, with given owner, using
* given table. The table's length must be an exponent of 2.
*/
private ScopeImpl(ScopeImpl next, Symbol owner, Entry[] table) {
super(owner);
this.next = next;
Assert.check(owner != null);
this.table = table;
this.hashMask = table.length - 1;
}
/** Convenience constructor used for dup and dupUnshared. */
private ScopeImpl(ScopeImpl next, Symbol owner, Entry[] table, int nelems) {
this(next, owner, table);
this.nelems = nelems;
}
/** Construct a new scope, within scope next, with given owner,
* using a fresh table of length INITIAL_SIZE.
*/
public ScopeImpl(Symbol owner) {
this(null, owner, new Entry[INITIAL_SIZE]);
}
/** Construct a fresh scope within this scope, with new owner,
* which shares its table with the outer scope. Used in connection with
* method leave if scope access is stack-like in order to avoid allocation
* of fresh tables.
*/
public WriteableScope dup(Symbol newOwner) {
ScopeImpl result = new ScopeImpl(this, newOwner, this.table, this.nelems);
shared++;
// System.out.println("====> duping scope " + this.hashCode() + " owned by " + newOwner + " to " + result.hashCode());
// new Error().printStackTrace(System.out);
return result;
}
/** Construct a fresh scope within this scope, with new owner,
* with a new hash table, whose contents initially are those of
* the table of its outer scope.
*/
public WriteableScope dupUnshared(Symbol newOwner) {
if (shared > 0) {
//The nested Scopes might have already added something to the table, so all items
//that don't originate in this Scope or any of its outer Scopes need to be cleared:
Set<Scope> acceptScopes = Collections.newSetFromMap(new IdentityHashMap<>());
ScopeImpl c = this;
while (c != null) {
acceptScopes.add(c);
c = c.next;
}
int n = 0;
Entry[] oldTable = this.table;
Entry[] newTable = new Entry[this.table.length];
for (int i = 0; i < oldTable.length; i++) {
Entry e = oldTable[i];
while (e != null && e != sentinel && !acceptScopes.contains(e.scope)) {
e = e.shadowed;
}
if (e != null) {
n++;
newTable[i] = e;
}
}
return new ScopeImpl(this, newOwner, newTable, n);
} else {
return new ScopeImpl(this, newOwner, this.table.clone(), this.nelems);
}
}
/** Remove all entries of this scope from its table, if shared
* with next.
*/
public WriteableScope leave() {
Assert.check(shared == 0);
if (table != next.table) return next;
while (elems != null) {
int hash = getIndex(elems.sym.name);
Entry e = table[hash];
Assert.check(e == elems, elems.sym);
table[hash] = elems.shadowed;
elems = elems.sibling;
}
Assert.check(next.shared > 0);
next.shared--;
next.nelems = nelems;
// System.out.println("====> leaving scope " + this.hashCode() + " owned by " + this.owner + " to " + next.hashCode());
// new Error().printStackTrace(System.out);
return next;
}
/** Double size of hash table.
*/
private void dble() {
Assert.check(shared == 0);
Entry[] oldtable = table;
Entry[] newtable = new Entry[oldtable.length * 2];
for (ScopeImpl s = this; s != null; s = s.next) {
if (s.table == oldtable) {
Assert.check(s == this || s.shared != 0);
s.table = newtable;
s.hashMask = newtable.length - 1;
}
}
int n = 0;
for (int i = oldtable.length; --i >= 0; ) {
Entry e = oldtable[i];
if (e != null && e != sentinel) {
table[getIndex(e.sym.name)] = e;
n++;
}
}
// We don't need to update nelems for shared inherited scopes,
// since that gets handled by leave().
nelems = n;
}
/** Enter symbol sym in this scope.
*/
public void enter(Symbol sym) {
Assert.check(shared == 0);
if (nelems * 3 >= hashMask * 2)
dble();
int hash = getIndex(sym.name);
Entry old = table[hash];
if (old == null) {
old = sentinel;
nelems++;
}
Entry e = new Entry(sym, old, elems, this);
table[hash] = e;
elems = e;
//notify listeners
listeners.symbolAdded(sym, this);
}
/** Remove symbol from this scope.
*/
public void remove(Symbol sym) {
Assert.check(shared == 0);
Entry e = lookup(sym.name, candidate -> candidate == sym);
if (e.scope == null) return;
// remove e from table and shadowed list;
int i = getIndex(sym.name);
Entry te = table[i];
if (te == e)
table[i] = e.shadowed;
else while (true) {
if (te.shadowed == e) {
te.shadowed = e.shadowed;
break;
}
te = te.shadowed;
}
// remove e from elems and sibling list
te = elems;
if (te == e)
elems = e.sibling;
else while (true) {
if (te.sibling == e) {
te.sibling = e.sibling;
break;
}
te = te.sibling;
}
removeCount++;
//notify listeners
listeners.symbolRemoved(sym, this);
}
/** Enter symbol sym in this scope if not already there.
*/
public void enterIfAbsent(Symbol sym) {
Assert.check(shared == 0);
Entry e = lookup(sym.name);
while (e.scope == this && e.sym.kind != sym.kind) e = e.next();
if (e.scope != this) enter(sym);
}
/** Given a class, is there already a class with same fully
* qualified name in this (import) scope?
*/
public boolean includes(Symbol c) {
for (Scope.Entry e = lookup(c.name);
e.scope == this;
e = e.next()) {
if (e.sym == c) return true;
}
return false;
}
/** Return the entry associated with given name, starting in
* this scope and proceeding outwards. If no entry was found,
* return the sentinel, which is characterized by having a null in
* both its scope and sym fields, whereas both fields are non-null
* for regular entries.
*/
protected Entry lookup(Name name) {
return lookup(name, noFilter);
}
protected Entry lookup(Name name, Filter<Symbol> sf) {
Entry e = table[getIndex(name)];
if (e == null || e == sentinel)
return sentinel;
while (e.scope != null && (e.sym.name != name || (sf != null && !sf.accepts(e.sym))))
e = e.shadowed;
return e;
}
public Symbol findFirst(Name name, Filter<Symbol> sf) {
return lookup(name, sf).sym;
}
/*void dump (java.io.PrintStream out) {
out.println(this);
for (int l=0; l < table.length; l++) {
Entry le = table[l];
out.print("#"+l+": ");
if (le==sentinel) out.println("sentinel");
else if(le == null) out.println("null");
else out.println(""+le+" s:"+le.sym);
}
}*/
/** Look for slot in the table.
* We use open addressing with double hashing.
*/
int getIndex (Name name) {
int h = name.hashCode();
int i = h & hashMask;
// The expression below is always odd, so it is guaranteed
// to be mutually prime with table.length, a power of 2.
int x = hashMask - ((h + (h >> 16)) << 1);
int d = -1; // Index of a deleted item.
for (;;) {
Entry e = table[i];
if (e == null)
return d >= 0 ? d : i;
if (e == sentinel) {
// We have to keep searching even if we see a deleted item.
// However, remember the index in case we fail to find the name.
if (d < 0)
d = i;
} else if (e.sym.name == name)
return i;
i = (i + x) & hashMask;
}
}
public boolean anyMatch(Filter<Symbol> sf) {
return getSymbols(sf, NON_RECURSIVE).iterator().hasNext();
}
public Iterable<Symbol> getSymbols(final Filter<Symbol> sf,
final LookupKind lookupKind) {
return new Iterable<Symbol>() {
public Iterator<Symbol> iterator() {
return new Iterator<Symbol>() {
private ScopeImpl currScope = ScopeImpl.this;
private Scope.Entry currEntry = elems;
private int seenRemoveCount = currScope.removeCount;
{
update();
}
public boolean hasNext() {
if (seenRemoveCount != currScope.removeCount &&
currEntry != null &&
!currEntry.scope.includes(currEntry.sym)) {
doNext(); //skip entry that is no longer in the Scope
seenRemoveCount = currScope.removeCount;
}
return currEntry != null;
}
public Symbol next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
return doNext();
}
private Symbol doNext() {
Symbol sym = (currEntry == null ? null : currEntry.sym);
if (currEntry != null) {
currEntry = currEntry.sibling;
}
update();
return sym;
}
public void remove() {
throw new UnsupportedOperationException();
}
private void update() {
skipToNextMatchingEntry();
if (lookupKind == RECURSIVE) {
while (currEntry == null && currScope.next != null) {
currScope = currScope.next;
currEntry = currScope.elems;
seenRemoveCount = currScope.removeCount;
skipToNextMatchingEntry();
}
}
}
void skipToNextMatchingEntry() {
while (currEntry != null && sf != null && !sf.accepts(currEntry.sym)) {
currEntry = currEntry.sibling;
}
}
};
}
};
}
public Iterable<Symbol> getSymbolsByName(final Name name,
final Filter<Symbol> sf,
final LookupKind lookupKind) {
return new Iterable<Symbol>() {
public Iterator<Symbol> iterator() {
return new Iterator<Symbol>() {
Scope.Entry currentEntry = lookup(name, sf);
int seenRemoveCount = currentEntry.scope != null ?
currentEntry.scope.removeCount : -1;
public boolean hasNext() {
if (currentEntry.scope != null &&
seenRemoveCount != currentEntry.scope.removeCount &&
!currentEntry.scope.includes(currentEntry.sym)) {
doNext(); //skip entry that is no longer in the Scope
}
return currentEntry.scope != null &&
(lookupKind == RECURSIVE ||
currentEntry.scope == ScopeImpl.this);
}
public Symbol next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
return doNext();
}
private Symbol doNext() {
Scope.Entry prevEntry = currentEntry;
currentEntry = currentEntry.next(sf);
return prevEntry.sym;
}
public void remove() {
throw new UnsupportedOperationException();
}
};
}
};
}
public Scope getOrigin(Symbol s) {
for (Scope.Entry e = lookup(s.name); e.scope != null ; e = e.next()) {
if (e.sym == s) {
return this;
}
}
return null;
}
@Override
public boolean isStaticallyImported(Symbol s) {
return false;
}
public String toString() {
StringBuilder result = new StringBuilder();
result.append("Scope[");
for (ScopeImpl s = this; s != null ; s = s.next) {
if (s != this) result.append(" | ");
for (Entry e = s.elems; e != null; e = e.sibling) {
if (e != s.elems) result.append(", ");
result.append(e.sym);
}
}
result.append("]");
return result.toString();
}
}
/** A class for scope entries.
*/
private static class Entry {
/** The referenced symbol.
* sym == null iff this == sentinel
*/
public Symbol sym;
/** An entry with the same hash code, or sentinel.
*/
private Entry shadowed;
/** Next entry in same scope.
*/
public Entry sibling;
/** The entry's scope.
* scope == null iff this == sentinel
*/
public ScopeImpl scope;
public Entry(Symbol sym, Entry shadowed, Entry sibling, ScopeImpl scope) {
this.sym = sym;
this.shadowed = shadowed;
this.sibling = sibling;
this.scope = scope;
}
/** Return next entry with the same name as this entry, proceeding
* outwards if not found in this scope.
*/
public Entry next() {
return shadowed;
}
public Entry next(Filter<Symbol> sf) {
if (shadowed.sym == null || sf == null || sf.accepts(shadowed.sym)) return shadowed;
else return shadowed.next(sf);
}
}
public static class ImportScope extends CompoundScope {
public ImportScope(Symbol owner) {
super(owner);
}
/**Finalize the content of the ImportScope to speed-up future lookups.
* No further changes to class hierarchy or class content will be reflected.
*/
public void finalizeScope() {
for (List<Scope> scopes = this.subScopes; scopes.nonEmpty(); scopes = scopes.tail) {
Scope impScope = scopes.head;
if (impScope instanceof FilterImportScope && impScope.owner.kind == Kind.TYP) {
WriteableScope finalized = WriteableScope.create(impScope.owner);
for (Symbol sym : impScope.getSymbols()) {
finalized.enter(sym);
}
finalized.listeners.add(new ScopeListener() {
@Override
public void symbolAdded(Symbol sym, Scope s) {
Assert.error("The scope is sealed.");
}
@Override
public void symbolRemoved(Symbol sym, Scope s) {
Assert.error("The scope is sealed.");
}
});
scopes.head = finalized;
}
}
}
}
public static class NamedImportScope extends ImportScope {
public NamedImportScope(Symbol owner, Scope currentFileScope) {
super(owner);
prependSubScope(currentFileScope);
}
public Scope importByName(Types types, Scope origin, Name name, ImportFilter filter, JCImport imp, BiConsumer<JCImport, CompletionFailure> cfHandler) {
return appendScope(new FilterImportScope(types, origin, name, filter, imp, cfHandler));
}
public Scope importType(Scope delegate, Scope origin, Symbol sym) {
return appendScope(new SingleEntryScope(delegate.owner, sym, origin));
}
private Scope appendScope(Scope newScope) {
List<Scope> existingScopes = this.subScopes.reverse();
subScopes = List.of(existingScopes.head);
subScopes = subScopes.prepend(newScope);
for (Scope s : existingScopes.tail) {
subScopes = subScopes.prepend(s);
}
return newScope;
}
private static class SingleEntryScope extends Scope {
private final Symbol sym;
private final List<Symbol> content;
private final Scope origin;
public SingleEntryScope(Symbol owner, Symbol sym, Scope origin) {
super(owner);
this.sym = sym;
this.content = List.of(sym);
this.origin = origin;
}
@Override
public Iterable<Symbol> getSymbols(Filter<Symbol> sf, LookupKind lookupKind) {
return sf == null || sf.accepts(sym) ? content : Collections.<Symbol>emptyList();
}
@Override
public Iterable<Symbol> getSymbolsByName(Name name,
Filter<Symbol> sf,
LookupKind lookupKind) {
return sym.name == name &&
(sf == null || sf.accepts(sym)) ? content : Collections.<Symbol>emptyList();
}
@Override
public Scope getOrigin(Symbol byName) {
return sym == byName ? origin : null;
}
@Override
public boolean isStaticallyImported(Symbol byName) {
return false;
}
}
}
public static class StarImportScope extends ImportScope {
public StarImportScope(Symbol owner) {
super(owner);
}
public void importAll(Types types, Scope origin,
ImportFilter filter,
JCImport imp,
BiConsumer<JCImport, CompletionFailure> cfHandler) {
for (Scope existing : subScopes) {
Assert.check(existing instanceof FilterImportScope);
FilterImportScope fis = (FilterImportScope) existing;
if (fis.origin == origin && fis.filter == filter &&
fis.imp.staticImport == imp.staticImport)
return ; //avoid entering the same scope twice
}
prependSubScope(new FilterImportScope(types, origin, null, filter, imp, cfHandler));
}
public boolean isFilled() {
return subScopes.nonEmpty();
}
}
public interface ImportFilter {
public boolean accepts(Scope origin, Symbol sym);
}
private static class FilterImportScope extends Scope {
private final Types types;
private final Scope origin;
private final Name filterName;
private final ImportFilter filter;
private final JCImport imp;
private final BiConsumer<JCImport, CompletionFailure> cfHandler;
public FilterImportScope(Types types,
Scope origin,
Name filterName,
ImportFilter filter,
JCImport imp,
BiConsumer<JCImport, CompletionFailure> cfHandler) {
super(origin.owner);
this.types = types;
this.origin = origin;
this.filterName = filterName;
this.filter = filter;
this.imp = imp;
this.cfHandler = cfHandler;
}
@Override
public Iterable<Symbol> getSymbols(final Filter<Symbol> sf, final LookupKind lookupKind) {
if (filterName != null)
return getSymbolsByName(filterName, sf, lookupKind);
try {
SymbolImporter si = new SymbolImporter(imp.staticImport) {
@Override
Iterable<Symbol> doLookup(TypeSymbol tsym) {
return tsym.members().getSymbols(sf, lookupKind);
}
};
return si.importFrom((TypeSymbol) origin.owner) :: iterator;
} catch (CompletionFailure cf) {
cfHandler.accept(imp, cf);
return Collections.emptyList();
}
}
@Override
public Iterable<Symbol> getSymbolsByName(final Name name,
final Filter<Symbol> sf,
final LookupKind lookupKind) {
if (filterName != null && filterName != name)
return Collections.emptyList();
try {
SymbolImporter si = new SymbolImporter(imp.staticImport) {
@Override
Iterable<Symbol> doLookup(TypeSymbol tsym) {
return tsym.members().getSymbolsByName(name, sf, lookupKind);
}
};
return si.importFrom((TypeSymbol) origin.owner) :: iterator;
} catch (CompletionFailure cf) {
cfHandler.accept(imp, cf);
return Collections.emptyList();
}
}
@Override
public Scope getOrigin(Symbol byName) {
return origin;
}
@Override
public boolean isStaticallyImported(Symbol byName) {
return imp.staticImport;
}
abstract class SymbolImporter {
Set<Symbol> processed = new HashSet<>();
List<Iterable<Symbol>> delegates = List.nil();
final boolean inspectSuperTypes;
public SymbolImporter(boolean inspectSuperTypes) {
this.inspectSuperTypes = inspectSuperTypes;
}
Stream<Symbol> importFrom(TypeSymbol tsym) {
if (tsym == null || !processed.add(tsym))
return Stream.empty();
Stream<Symbol> result = Stream.empty();
if (inspectSuperTypes) {
// also import inherited names
result = importFrom(types.supertype(tsym.type).tsym);
for (Type t : types.interfaces(tsym.type))
result = Stream.concat(importFrom(t.tsym), result);
}
return Stream.concat(StreamSupport.stream(doLookup(tsym).spliterator(), false)
.filter(s -> filter.accepts(origin, s)),
result);
}
abstract Iterable<Symbol> doLookup(TypeSymbol tsym);
}
}
/** A class scope adds capabilities to keep track of changes in related
* class scopes - this allows client to realize whether a class scope
* has changed, either directly (because a new member has been added/removed
* to this scope) or indirectly (i.e. because a new member has been
* added/removed into a supertype scope)
*/
public static class CompoundScope extends Scope implements ScopeListener {
List<Scope> subScopes = List.nil();
private int mark = 0;
public CompoundScope(Symbol owner) {
super(owner);
}
public void prependSubScope(Scope that) {
if (that != null) {
subScopes = subScopes.prepend(that);
that.listeners.add(this);
mark++;
listeners.symbolAdded(null, this);
}
}
public void symbolAdded(Symbol sym, Scope s) {
mark++;
listeners.symbolAdded(sym, s);
}
public void symbolRemoved(Symbol sym, Scope s) {
mark++;
listeners.symbolRemoved(sym, s);
}
public int getMark() {
return mark;
}
@Override
public String toString() {
StringBuilder buf = new StringBuilder();
buf.append("CompoundScope{");
String sep = "";
for (Scope s : subScopes) {
buf.append(sep);
buf.append(s);
sep = ",";
}
buf.append("}");
return buf.toString();
}
@Override
public Iterable<Symbol> getSymbols(final Filter<Symbol> sf,
final LookupKind lookupKind) {
return () -> Iterators.createCompoundIterator(subScopes,
scope -> scope.getSymbols(sf,
lookupKind)
.iterator());
}
@Override
public Iterable<Symbol> getSymbolsByName(final Name name,
final Filter<Symbol> sf,
final LookupKind lookupKind) {
return () -> Iterators.createCompoundIterator(subScopes,
scope -> scope.getSymbolsByName(name,
sf,
lookupKind)
.iterator());
}
@Override
public Scope getOrigin(Symbol sym) {
for (Scope delegate : subScopes) {
if (delegate.includes(sym))
return delegate.getOrigin(sym);
}
return null;
}
@Override
public boolean isStaticallyImported(Symbol sym) {
for (Scope delegate : subScopes) {
if (delegate.includes(sym))
return delegate.isStaticallyImported(sym);
}
return false;
}
}
/** An error scope, for which the owner should be an error symbol. */
public static class ErrorScope extends ScopeImpl {
ErrorScope(ScopeImpl next, Symbol errSymbol, Entry[] table) {
super(next, /*owner=*/errSymbol, table);
}
public ErrorScope(Symbol errSymbol) {
super(errSymbol);
}
public WriteableScope dup(Symbol newOwner) {
return new ErrorScope(this, newOwner, table);
}
public WriteableScope dupUnshared(Symbol newOwner) {
return new ErrorScope(this, newOwner, table.clone());
}
public Entry lookup(Name name) {
Entry e = super.lookup(name);
if (e.scope == null)
return new Entry(owner, null, null, null);
else
return e;
}
}
}