1 files changed, 79 insertions, 0 deletions
diff --git a/csharp/ProtocolBuffers/FieldAccess/SinglePrimitiveAccessor.cs b/csharp/ProtocolBuffers/FieldAccess/SinglePrimitiveAccessor.cs
new file mode 100644
index 00000000..4878e79b
--- /dev/null
+++ b/csharp/ProtocolBuffers/FieldAccess/SinglePrimitiveAccessor.cs
@@ -0,0 +1,79 @@
+using System;
+using System.Reflection;
+using Google.ProtocolBuffers.Descriptors;
+
+namespace Google.ProtocolBuffers.FieldAccess {
+  /// <summary>
+  /// Access for a non-repeated field of a "primitive" type (i.e. not another message or an enum).
+  /// </summary>
+  internal class SinglePrimitiveAccessor : IFieldAccessor {
+
+    private readonly PropertyInfo messageProperty;
+    private readonly PropertyInfo builderProperty;
+    private readonly PropertyInfo hasProperty;
+    private readonly MethodInfo clearMethod;
+
+    /// <summary>
+    /// The CLR type of the field (int, the enum type, ByteString, the message etc).
+    /// As declared by the property.
+    /// </summary>
+    protected Type ClrType {
+      get { return messageProperty.PropertyType; }
+    }
+
+    internal SinglePrimitiveAccessor(string name, Type messageType, Type builderType) {
+      messageProperty = messageType.GetProperty(name);
+      builderProperty = builderType.GetProperty(name);
+      hasProperty = messageType.GetProperty("Has" + name);
+      clearMethod = builderType.GetMethod("Clear" + name);
+      if (messageProperty == null || builderProperty == null || hasProperty == null || clearMethod == null) {
+        throw new ArgumentException("Not all required properties/methods available");
+      }
+    }
+
+    public bool Has(IMessage message) {
+      return (bool) hasProperty.GetValue(message, null);
+    }
+
+    public void Clear(IBuilder builder) {
+      clearMethod.Invoke(builder, null);
+    }
+
+    /// <summary>
+    /// Only valid for message types - this implementation throws InvalidOperationException.
+    /// </summary>
+    public virtual IBuilder CreateBuilder() {
+      throw new InvalidOperationException();
+    }
+
+    public virtual object GetValue(IMessage message) {
+      return messageProperty.GetValue(message, null);
+    }
+
+    public virtual void SetValue(IBuilder builder, object value) {
+      builderProperty.SetValue(builder, value, null);
+    }
+
+    #region Methods only related to repeated values
+    public int GetRepeatedCount(IMessage message) {
+      throw new InvalidOperationException();
+    }
+
+    public object GetRepeatedValue(IMessage message, int index) {
+      throw new InvalidOperationException();
+    }
+
+    public void SetRepeated(IBuilder builder, int index, object value) {
+      throw new InvalidOperationException();
+    }
+
+    public void AddRepeated(IBuilder builder, object value) {
+      throw new InvalidOperationException();
+    }
+
+    public object GetRepeatedWrapper(IBuilder builder) {
+      throw new InvalidOperationException();
+    }
+    #endregion
+  }
+}
+\ No newline at end of file