diff options
Diffstat (limited to 'csharp/src/Google.Protobuf/Collections/MapField.cs')
| -rw-r--r-- | csharp/src/Google.Protobuf/Collections/MapField.cs | 76 |
1 files changed, 32 insertions, 44 deletions
diff --git a/csharp/src/Google.Protobuf/Collections/MapField.cs b/csharp/src/Google.Protobuf/Collections/MapField.cs index c0ed28ae..993a89d7 100644 --- a/csharp/src/Google.Protobuf/Collections/MapField.cs +++ b/csharp/src/Google.Protobuf/Collections/MapField.cs @@ -34,6 +34,7 @@ using Google.Protobuf.Reflection; using System; using System.Collections; using System.Collections.Generic; +using System.IO; using System.Linq; using System.Text; using Google.Protobuf.Compatibility; @@ -53,6 +54,13 @@ namespace Google.Protobuf.Collections /// For string keys, the equality comparison is provided by <see cref="StringComparer.Ordinal" />. /// </para> /// <para> + /// Null values are not permitted in the map, either for wrapper types or regular messages. + /// If a map is deserialized from a data stream and the value is missing from an entry, a default value + /// is created instead. For primitive types, that is the regular default value (0, the empty string and so + /// on); for message types, an empty instance of the message is created, as if the map entry contained a 0-length + /// encoded value for the field. + /// </para> + /// <para> /// This implementation does not generally prohibit the use of key/value types which are not /// supported by Protocol Buffers (e.g. using a key type of <code>byte</code>) but nor does it guarantee /// that all operations will work in such cases. @@ -61,35 +69,11 @@ namespace Google.Protobuf.Collections public sealed class MapField<TKey, TValue> : IDeepCloneable<MapField<TKey, TValue>>, IDictionary<TKey, TValue>, IEquatable<MapField<TKey, TValue>>, IDictionary { // TODO: Don't create the map/list until we have an entry. (Assume many maps will be empty.) - private readonly bool allowNullValues; private readonly Dictionary<TKey, LinkedListNode<KeyValuePair<TKey, TValue>>> map = new Dictionary<TKey, LinkedListNode<KeyValuePair<TKey, TValue>>>(); private readonly LinkedList<KeyValuePair<TKey, TValue>> list = new LinkedList<KeyValuePair<TKey, TValue>>(); /// <summary> - /// Constructs a new map field, defaulting the value nullability to only allow null values for message types - /// and non-nullable value types. - /// </summary> - public MapField() : this(typeof(IMessage).IsAssignableFrom(typeof(TValue)) || Nullable.GetUnderlyingType(typeof(TValue)) != null) - { - } - - /// <summary> - /// Constructs a new map field, overriding the choice of whether null values are permitted in the map. - /// This is used by wrapper types, where maps with string and bytes wrappers as the value types - /// support null values. - /// </summary> - /// <param name="allowNullValues">Whether null values are permitted in the map or not.</param> - public MapField(bool allowNullValues) - { - if (allowNullValues && typeof(TValue).IsValueType() && Nullable.GetUnderlyingType(typeof(TValue)) == null) - { - throw new ArgumentException("allowNullValues", "Non-nullable value types do not support null values"); - } - this.allowNullValues = allowNullValues; - } - - /// <summary> /// Creates a deep clone of this object. /// </summary> /// <returns> @@ -97,13 +81,13 @@ namespace Google.Protobuf.Collections /// </returns> public MapField<TKey, TValue> Clone() { - var clone = new MapField<TKey, TValue>(allowNullValues); + var clone = new MapField<TKey, TValue>(); // Keys are never cloneable. Values might be. if (typeof(IDeepCloneable<TValue>).IsAssignableFrom(typeof(TValue))) { foreach (var pair in list) { - clone.Add(pair.Key, pair.Value == null ? pair.Value : ((IDeepCloneable<TValue>)pair.Value).Clone()); + clone.Add(pair.Key, ((IDeepCloneable<TValue>)pair.Value).Clone()); } } else @@ -140,7 +124,7 @@ namespace Google.Protobuf.Collections /// <returns><c>true</c> if the map contains the given key; <c>false</c> otherwise.</returns> public bool ContainsKey(TKey key) { - Preconditions.CheckNotNullUnconstrained(key, "key"); + ProtoPreconditions.CheckNotNullUnconstrained(key, "key"); return map.ContainsKey(key); } @@ -157,7 +141,7 @@ namespace Google.Protobuf.Collections /// <returns><c>true</c> if the map contained the given key before the entry was removed; <c>false</c> otherwise.</returns> public bool Remove(TKey key) { - Preconditions.CheckNotNullUnconstrained(key, "key"); + ProtoPreconditions.CheckNotNullUnconstrained(key, "key"); LinkedListNode<KeyValuePair<TKey, TValue>> node; if (map.TryGetValue(key, out node)) { @@ -205,7 +189,7 @@ namespace Google.Protobuf.Collections { get { - Preconditions.CheckNotNullUnconstrained(key, "key"); + ProtoPreconditions.CheckNotNullUnconstrained(key, "key"); TValue value; if (TryGetValue(key, out value)) { @@ -215,11 +199,11 @@ namespace Google.Protobuf.Collections } set { - Preconditions.CheckNotNullUnconstrained(key, "key"); + ProtoPreconditions.CheckNotNullUnconstrained(key, "key"); // value == null check here is redundant, but avoids boxing. - if (value == null && !allowNullValues) + if (value == null) { - Preconditions.CheckNotNullUnconstrained(value, "value"); + ProtoPreconditions.CheckNotNullUnconstrained(value, "value"); } LinkedListNode<KeyValuePair<TKey, TValue>> node; var pair = new KeyValuePair<TKey, TValue>(key, value); @@ -246,12 +230,12 @@ namespace Google.Protobuf.Collections public ICollection<TValue> Values { get { return new MapView<TValue>(this, pair => pair.Value, ContainsValue); } } /// <summary> - /// Adds the specified entries to the map. + /// Adds the specified entries to the map. The keys and values are not automatically cloned. /// </summary> /// <param name="entries">The entries to add to the map.</param> public void Add(IDictionary<TKey, TValue> entries) { - Preconditions.CheckNotNull(entries, "entries"); + ProtoPreconditions.CheckNotNull(entries, "entries"); foreach (var pair in entries) { Add(pair.Key, pair.Value); @@ -347,11 +331,6 @@ namespace Google.Protobuf.Collections } /// <summary> - /// Returns whether or not this map allows values to be null. - /// </summary> - public bool AllowsNullValues { get { return allowNullValues; } } - - /// <summary> /// Gets the number of elements contained in the map. /// </summary> public int Count { get { return list.Count; } } @@ -496,9 +475,9 @@ namespace Google.Protobuf.Collections /// </summary> public override string ToString() { - var builder = new StringBuilder(); - JsonFormatter.Default.WriteDictionary(builder, this); - return builder.ToString(); + var writer = new StringWriter(); + JsonFormatter.Default.WriteDictionary(writer, this); + return writer.ToString(); } #region IDictionary explicit interface implementation @@ -523,7 +502,7 @@ namespace Google.Protobuf.Collections void IDictionary.Remove(object key) { - Preconditions.CheckNotNull(key, "key"); + ProtoPreconditions.CheckNotNull(key, "key"); if (!(key is TKey)) { return; @@ -552,7 +531,7 @@ namespace Google.Protobuf.Collections { get { - Preconditions.CheckNotNull(key, "key"); + ProtoPreconditions.CheckNotNull(key, "key"); if (!(key is TKey)) { return null; @@ -632,6 +611,8 @@ namespace Google.Protobuf.Collections /// </summary> internal class MessageAdapter : IMessage { + private static readonly byte[] ZeroLengthMessageStreamData = new byte[] { 0 }; + private readonly Codec codec; internal TKey Key { get; set; } internal TValue Value { get; set; } @@ -665,6 +646,13 @@ namespace Google.Protobuf.Collections input.SkipLastField(); } } + + // Corner case: a map entry with a key but no value, where the value type is a message. + // Read it as if we'd seen an input stream with no data (i.e. create a "default" message). + if (Value == null) + { + Value = codec.valueCodec.Read(new CodedInputStream(ZeroLengthMessageStreamData)); + } } public void WriteTo(CodedOutputStream output) |