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Interface uhr.core.msg.MessageReceiver

public interface MessageReceiver
This widely used interface allows message transport from one thimg to another. This is a powerful loose coupling mechanism that is at the heart of UHR. There are several uses for MessageReceiver. Together they allow "message chains" to provide a system of parts with the equivalent of a central nervous system.
1. Message input to a part. The part never knows where the message comes from, or whether it's a normal or service Message. Generally the part will check the message name and use one public or protected method per message property supported, unless trivial. The use of those public methods allows the flexibility of direct links (with interfaces) or use of messages. We may need a design standard here.

2. Sending a message out of a part. This always happens when a message is first sent from a MessageSender. It also occurs behind the scenes when a message is forwarded from one MessageRouter to another MessageRouter.

3. Monitoring messages in a MessageRouter. This is handy for tools and advanced domain parts. For example is allows system animation by visually showing the flow of messages.

If the message is not expected the class should not throw an exception, but it may complain such as by printing that it's ignoring the message name.

The receiver should NOT keep a reference to the message, to allow the sender to reuse message objects. If a reference is needed, do a clone or such.

Method Index

o receive(Message)
The class should receieve the message and react intelligently.

Methods

o receive 
 public abstract void receive(Message message)
The class should receieve the message and react intelligently. :-)

The class should check the message name and then do something per name, much like a method. Remember, the message name is interned, so == comparison may be used since it's faster and more concise.

Parameters:
message - the incoming message. 
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