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
|
// Copyright 2018 The Bazel Authors. 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.devtools.build.lib.skyframe.serialization;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSortedMap;
import com.google.common.collect.Ordering;
import com.google.protobuf.CodedInputStream;
import com.google.protobuf.CodedOutputStream;
import java.io.IOException;
import java.util.Comparator;
import java.util.Map;
/**
* Encodes an {@link ImmutableMap}, which may be an {@link ImmutableSortedMap}. The iteration order
* of the deserialized map is the same as the original map's.
*
* <p>We handle both {@link ImmutableMap} and {@link ImmutableSortedMap} here because we cannot
* handle {@link ImmutableSortedMap} with any ordering other than the default, and so we degrade to
* ImmutableMap in that case, hoping that the caller does not notice. Since the ordering is
* preserved, the caller should not be sensitive to this change unless the caller's field is
* declared to be an {@link ImmutableSortedMap}, in which case we will crash at runtime.
*
* <p>Any {@link SerializationException} or {@link IOException} that arises while serializing or
* deserializing a map entry's value (not its key) will be wrapped in a new {@link
* SerializationException} using {@link SerializationException#propagate}. (Note that this preserves
* the type of {@link SerializationException.NoCodecException} exceptions.) The message will include
* the {@code toString()} of the entry's key. For errors that occur while serializing, it will also
* include the class name of the entry's value. Errors that occur while serializing an entry key are
* not affected.
*
* <p>Because of the ambiguity around the key type (Comparable in the case of {@link
* ImmutableSortedMap}, arbitrary otherwise, we avoid specifying the key type as a parameter.
*/
class ImmutableMapCodec<V> implements ObjectCodec<ImmutableMap<?, V>> {
@SuppressWarnings("unchecked")
@Override
public Class<ImmutableMap<?, V>> getEncodedClass() {
// Because Java disallows converting from Class<ImmutableMap> to Class<ImmutableMap<?, ?>>
// directly.
return (Class<ImmutableMap<?, V>>) ((Class<?>) ImmutableMap.class);
}
@Override
public void serialize(
SerializationContext context, ImmutableMap<?, V> map, CodedOutputStream codedOut)
throws SerializationException, IOException {
codedOut.writeInt32NoTag(map.size());
boolean serializeAsSortedMap = false;
if (map instanceof ImmutableSortedMap) {
Comparator<?> comparator = ((ImmutableSortedMap<?, ?>) map).comparator();
// In practice the comparator seems to always be Ordering.natural(), but be flexible.
serializeAsSortedMap =
comparator.equals(Ordering.natural()) || comparator.equals(Comparator.naturalOrder());
}
codedOut.writeBoolNoTag(serializeAsSortedMap);
for (Map.Entry<?, ?> entry : map.entrySet()) {
context.serialize(entry.getKey(), codedOut);
try {
context.serialize(entry.getValue(), codedOut);
} catch (SerializationException | IOException e) {
throw SerializationException.propagate(
String.format(
"Exception while serializing value of type %s for key '%s'",
entry.getValue().getClass().getName(), entry.getKey()),
e);
}
}
}
@Override
public ImmutableMap<?, V> deserialize(DeserializationContext context, CodedInputStream codedIn)
throws SerializationException, IOException {
int length = codedIn.readInt32();
if (length < 0) {
throw new SerializationException("Expected non-negative length: " + length);
}
if (codedIn.readBool()) {
return buildMap(ImmutableSortedMap.naturalOrder(), length, context, codedIn);
} else {
return buildMap(ImmutableMap.builderWithExpectedSize(length), length, context, codedIn);
}
}
private static <K, V> ImmutableMap<K, V> buildMap(
ImmutableMap.Builder<K, V> builder,
int length,
DeserializationContext context,
CodedInputStream codedIn)
throws IOException, SerializationException {
for (int i = 0; i < length; i++) {
K key = context.deserialize(codedIn);
V value;
try {
value = context.deserialize(codedIn);
} catch (SerializationException | IOException e) {
throw SerializationException.propagate(
String.format("Exception while deserializing value for key '%s'", key), e);
}
builder.put(key, value);
}
try {
return builder.build();
} catch (IllegalArgumentException e) {
throw new SerializationException(
"Duplicate keys during ImmutableMapCodec deserialization", e);
}
}
}
|
