#region License
/*
* Copyright 2002-2006 the original author or authors.
*
* 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.
*/
#endregion
using System;
using System.Collections;
using System.Runtime.Serialization;
using Apache.NMS;
namespace Spring.Messaging.Nms.Support.Converter{
/// <summary> A simple message converter that can handle ITextMessages, IBytesMessages,
/// IMapMessages, and IObjectMessages. Used as default by NmsTemplate, for
/// <code>ConvertAndSend</code> and <code>ReceiveAndConvert</code> operations.
///
/// <p>Converts a String to a NMS ITextMessage, a byte array to a NMS IBytesMessage,
/// a Map to a NMS IMapMessage, and a Serializable object to a NMS IObjectMessage
/// (or vice versa).</p>
///
///
/// </summary>
/// <author>Juergen Hoeller</author>
/// <author>Mark Pollack (.NET)</author>
public class SimpleMessageConverter : IMessageConverter
{
/// <summary> Convert a .NET object to a NMS Message using the supplied session
/// to create the message object.
/// </summary>
/// <param name="objectToConvert">the object to convert
/// </param>
/// <param name="session">the Session to use for creating a NMS Message
/// </param>
/// <returns> the NMS Message
/// </returns>
/// <throws>NMSException if thrown by NMS API methods </throws>
/// <throws>MessageConversionException in case of conversion failure </throws>
public IMessage ToMessage(object objectToConvert, ISession session)
{
if (objectToConvert is IMessage)
{
return (IMessage) objectToConvert;
}
else if (objectToConvert is string)
{
return CreateMessageForString((string) objectToConvert, session);
}
else if (objectToConvert is sbyte[])
{
return CreateMessageForByteArray((byte[]) objectToConvert, session);
}
else if (objectToConvert is IDictionary)
{
return CreateMessageForMap((IDictionary) objectToConvert, session);
}
else if (objectToConvert != null && objectToConvert.GetType().IsSerializable)
{
return
CreateMessageForSerializable(objectToConvert, session);
}
else
{
throw new MessageConversionException("Cannot convert object [" + objectToConvert + "] to NMS message");
}
}
/// <summary> Convert from a NMS Message to a .NET object.</summary>
/// <param name="messageToConvert">the message to convert
/// </param>
/// <returns> the converted .NET object
/// </returns>
/// <throws>MessageConversionException in case of conversion failure </throws>
public object FromMessage(IMessage messageToConvert)
{
if (messageToConvert is ITextMessage)
{
return ExtractStringFromMessage((ITextMessage) messageToConvert);
}
else if (messageToConvert is IBytesMessage)
{
return ExtractByteArrayFromMessage((IBytesMessage) messageToConvert);
}
else if (messageToConvert is IMapMessage)
{
return ExtractMapFromMessage((IMapMessage) messageToConvert);
}
else if (messageToConvert is IObjectMessage)
{
return ExtractSerializableFromMessage((IObjectMessage) messageToConvert);
}
else
{
return messageToConvert;
}
}
#region To Converter Methods
/// <summary> Create a NMS ITextMessage for the given String.</summary>
/// <param name="text">the String to convert
/// </param>
/// <param name="session">current NMS session
/// </param>
/// <returns> the resulting message
/// </returns>
/// <throws> NMSException if thrown by NMS methods </throws>
protected virtual ITextMessage CreateMessageForString(string text, ISession session)
{
return session.CreateTextMessage((text));
}
/// <summary> Create a NMS IBytesMessage for the given byte array.</summary>
/// <param name="bytes">the byyte array to convert
/// </param>
/// <param name="session">current NMS session
/// </param>
/// <returns> the resulting message
/// </returns>
/// <throws> NMSException if thrown by NMS methods </throws>
protected virtual IBytesMessage CreateMessageForByteArray(byte[] bytes, ISession session)
{
IBytesMessage message = session.CreateBytesMessage();
message.Content = bytes;
return message;
}
/// <summary> Create a NMS IMapMessage for the given Map.</summary>
/// <param name="map">the Map to convert
/// </param>
/// <param name="session">current NMS session
/// </param>
/// <returns> the resulting message
/// </returns>
/// <throws> NMSException if thrown by NMS methods </throws>
protected virtual IMapMessage CreateMessageForMap(IDictionary map, ISession session)
{
IMapMessage mapMessage = session.CreateMapMessage();
foreach (DictionaryEntry entry in map)
{
if (!(entry.Key is string))
{
//UPGRADE_TODO: The equivalent in .NET for method 'java.lang.Class.getName' may return a different value. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1043'"
throw new MessageConversionException("Cannot convert non-String key of type [" +
(entry.Key != null ? entry.Key.GetType().FullName : null) +
"] to IMapMessage entry");
}
mapMessage.Body[entry.Key.ToString()] = entry.Value;
}
return mapMessage;
}
/// <summary> Create a NMS IObjectMessage for the given Serializable object.</summary>
/// <param name="objectToSend">the Serializable object to convert
/// </param>
/// <param name="session">current NMS session
/// </param>
/// <returns> the resulting message
/// </returns>
/// <throws> NMSException if thrown by NMS methods </throws>
protected virtual IObjectMessage CreateMessageForSerializable(
object objectToSend, ISession session)
{
return session.CreateObjectMessage(objectToSend);
}
#endregion
#region From Converter Mehtods
/// <summary> Extract a String from the given ITextMessage.</summary>
/// <param name="message">the message to convert
/// </param>
/// <returns> the resulting String
/// </returns>
/// <throws> NMSException if thrown by NMS methods </throws>
protected virtual string ExtractStringFromMessage(ITextMessage message)
{
return message.Text;
}
/// <summary> Extract a byte array from the given IBytesMessage.</summary>
/// <param name="message">the message to convert
/// </param>
/// <returns> the resulting byte array
/// </returns>
/// <throws> NMSException if thrown by NMS methods </throws>
protected virtual byte[] ExtractByteArrayFromMessage(IBytesMessage message)
{
return message.Content;
}
/// <summary> Extract a IDictionary from the given IMapMessage.</summary>
/// <param name="message">the message to convert
/// </param>
/// <returns> the resulting Map
/// </returns>
/// <throws>NMSException if thrown by NMS methods </throws>
protected virtual IDictionary ExtractMapFromMessage(IMapMessage message)
{
IDictionary dictionary = new Hashtable();
IEnumerator e = message.Body.Keys.GetEnumerator();
while (e.MoveNext())
{
String key = (String) e.Current;
dictionary.Add(key, message.Body[key]);
}
return dictionary;
}
/// <summary>
/// Extracts the serializable object from the given object message.
/// </summary>
/// <param name="message">The message to convert.</param>
/// <returns>The resulting serializable object.</returns>
protected virtual object ExtractSerializableFromMessage(
IObjectMessage message)
{
return message.Body;
}
#endregion
}
}
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