1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
/*
* Copyright 2016 Google Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.turbine.binder;
import com.google.common.base.Joiner;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.turbine.binder.bound.HeaderBoundClass;
import com.google.turbine.binder.bound.PackageSourceBoundClass;
import com.google.turbine.binder.bound.SourceHeaderBoundClass;
import com.google.turbine.binder.env.Env;
import com.google.turbine.binder.env.LazyEnv.LazyBindingError;
import com.google.turbine.binder.lookup.LookupKey;
import com.google.turbine.binder.lookup.LookupResult;
import com.google.turbine.binder.sym.ClassSymbol;
import com.google.turbine.binder.sym.TyVarSymbol;
import com.google.turbine.diag.TurbineError.ErrorKind;
import com.google.turbine.diag.TurbineLog.TurbineLogWithSource;
import com.google.turbine.model.TurbineTyKind;
import com.google.turbine.tree.Tree;
import com.google.turbine.tree.Tree.ClassTy;
import java.util.ArrayDeque;
import java.util.LinkedHashMap;
import org.checkerframework.checker.nullness.qual.Nullable;
/** Type hierarchy binding. */
public class HierarchyBinder {
/** Binds the type hierarchy (superclasses and interfaces) for a single class. */
public static SourceHeaderBoundClass bind(
TurbineLogWithSource log,
ClassSymbol origin,
PackageSourceBoundClass base,
Env<ClassSymbol, ? extends HeaderBoundClass> env) {
return new HierarchyBinder(log, origin, base, env).bind();
}
private final TurbineLogWithSource log;
private final ClassSymbol origin;
private final PackageSourceBoundClass base;
private final Env<ClassSymbol, ? extends HeaderBoundClass> env;
private HierarchyBinder(
TurbineLogWithSource log,
ClassSymbol origin,
PackageSourceBoundClass base,
Env<ClassSymbol, ? extends HeaderBoundClass> env) {
this.log = log;
this.origin = origin;
this.base = base;
this.env = env;
}
private SourceHeaderBoundClass bind() {
Tree.TyDecl decl = base.decl();
ClassSymbol superclass;
if (decl.xtnds().isPresent()) {
superclass = resolveClass(decl.xtnds().get());
if (origin.equals(superclass)) {
log.error(decl.xtnds().get().position(), ErrorKind.CYCLIC_HIERARCHY, origin);
}
} else {
switch (decl.tykind()) {
case ENUM:
superclass = ClassSymbol.ENUM;
break;
case INTERFACE:
case ANNOTATION:
case CLASS:
superclass = !origin.equals(ClassSymbol.OBJECT) ? ClassSymbol.OBJECT : null;
break;
case RECORD:
superclass = ClassSymbol.RECORD;
break;
default:
throw new AssertionError(decl.tykind());
}
}
ImmutableList.Builder<ClassSymbol> interfaces = ImmutableList.builder();
if (!decl.impls().isEmpty()) {
for (Tree.ClassTy i : decl.impls()) {
ClassSymbol result = resolveClass(i);
if (result == null) {
continue;
}
if (origin.equals(result)) {
log.error(i.position(), ErrorKind.CYCLIC_HIERARCHY, origin);
}
interfaces.add(result);
}
} else {
if (decl.tykind() == TurbineTyKind.ANNOTATION) {
interfaces.add(ClassSymbol.ANNOTATION);
}
}
LinkedHashMap<String, TyVarSymbol> typeParameters = new LinkedHashMap<>();
for (Tree.TyParam p : decl.typarams()) {
TyVarSymbol existing =
typeParameters.putIfAbsent(p.name().value(), new TyVarSymbol(origin, p.name().value()));
if (existing != null) {
log.error(p.position(), ErrorKind.DUPLICATE_DECLARATION, p.name());
}
}
return new SourceHeaderBoundClass(
base, superclass, interfaces.build(), ImmutableMap.copyOf(typeParameters));
}
/**
* Resolves the {@link ClassSymbol} for the given {@link Tree.ClassTy}, with handling for
* non-canonical qualified type names.
*/
private @Nullable ClassSymbol resolveClass(Tree.ClassTy ty) {
// flatten a left-recursive qualified type name to its component simple names
// e.g. Foo<Bar>.Baz -> ["Foo", "Bar"]
ArrayDeque<Tree.Ident> flat = new ArrayDeque<>();
for (Tree.ClassTy curr = ty; curr != null; curr = curr.base().orElse(null)) {
flat.addFirst(curr.name());
}
// Resolve the base symbol in the qualified name.
LookupResult result = lookup(ty, new LookupKey(ImmutableList.copyOf(flat)));
if (result == null) {
log.error(ty.position(), ErrorKind.CANNOT_RESOLVE, Joiner.on('.').join(flat));
return null;
}
// Resolve pieces in the qualified name referring to member types.
// This needs to consider member type declarations inherited from supertypes and interfaces.
ClassSymbol sym = (ClassSymbol) result.sym();
for (Tree.Ident bit : result.remaining()) {
sym = resolveNext(ty, sym, bit);
if (sym == null) {
break;
}
}
return sym;
}
private @Nullable ClassSymbol resolveNext(ClassTy ty, ClassSymbol sym, Tree.Ident bit) {
ClassSymbol next;
try {
next = Resolve.resolve(env, origin, sym, bit);
} catch (LazyBindingError e) {
log.error(ty.position(), ErrorKind.CYCLIC_HIERARCHY, e.getMessage());
return null;
}
if (next == null) {
log.error(
bit.position(),
ErrorKind.SYMBOL_NOT_FOUND,
new ClassSymbol(sym.binaryName() + '$' + bit));
}
return next;
}
/** Resolve a qualified type name to a symbol. */
private @Nullable LookupResult lookup(Tree tree, LookupKey lookup) {
// Handle any lexically enclosing class declarations (if we're binding a member class).
// We could build out scopes for this, but it doesn't seem worth it. (And sharing the scopes
// with other members of the same enclosing declaration would be complicated.)
for (ClassSymbol curr = base.owner(); curr != null; curr = env.getNonNull(curr).owner()) {
ClassSymbol result;
try {
result = Resolve.resolve(env, origin, curr, lookup.first());
} catch (LazyBindingError e) {
log.error(tree.position(), ErrorKind.CYCLIC_HIERARCHY, e.getMessage());
result = null;
}
if (result != null) {
return new LookupResult(result, lookup);
}
}
// Fall back to the top-level scopes for the compilation unit (imports, same package, then
// qualified name resolution).
return base.scope().lookup(lookup, Resolve.resolveFunction(env, origin));
}
}
|
