Module dk.cloudcreate.essentials.components.foundation

Package dk.cloudcreate.essentials.components.foundation.messaging.eip.store_and_forward

Class PatternMatchingMessageHandler

java.lang.Object

dk.cloudcreate.essentials.components.foundation.messaging.eip.store_and_forward.PatternMatchingMessageHandler

All Implemented Interfaces:

Consumer<Message>

public class PatternMatchingMessageHandler
extends Object
implements Consumer<Message>

Pattern matching Consumer<Message> for use with Inboxes/Inbox or Outboxes/Outbox
The PatternMatchingMessageHandler will automatically call methods annotated with the @MessageHandler annotation and where the 1st argument matches the actual Message payload type (contained in the Message.getPayload() provided to the provided Consumer)

Each method may also include a 2nd argument that of type Message in which case the event that's being matched is included as the 2nd argument in the call to the method.
The methods can have any accessibility (private, public, etc.), they just have to be instance methods.

Example:

 public class MyMessageHandler extends PatternMatchingMessageHandler {

         @MessageHandler
         public void handle(OrderEvent.OrderAdded orderAdded) {
             ...
         }

         @MessageHandler
         private void handle(OrderEvent.ProductRemovedFromOrder productRemovedFromOrder, Message message) {
           ...
         }
 }
 

Constructor Summary

Constructors

Constructor	Description
PatternMatchingMessageHandler()	Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e.
PatternMatchingMessageHandler(Object invokeMessageHandlerMethodsOn)	Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e.
PatternMatchingMessageHandler(Object invokeMessageHandlerMethodsOn, List<MessageHandlerInterceptor> interceptors)	Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e.
PatternMatchingMessageHandler(List<MessageHandlerInterceptor> interceptors)	Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e.

Method Summary

Modifier and Type	Method	Description
void	accept(Message message)
PatternMatchingMessageHandler	addInterceptor(MessageHandlerInterceptor interceptor)
void	allowUnmatchedMessages()	Should the event handler allow unmatched Message.getPayload()? If true then an unmatched Message.getPayload() is ignored, if false (the default value) then an unmatched event will cause handleUnmatchedMessage(Message) will throw an IllegalArgumentException
boolean	handlesMessageWithPayload(Class<?> payloadType)	Check amongst all the MessageHandler annotated methods and check if there's a method that matches (i.e.
protected void	handleUnmatchedMessage(Message message)	Override this method to provide custom handling for Message's who's Message.getPayload() aren't matched Default behaviour is to throw an IllegalArgumentException unless isAllowUnmatchedMessages() is set to true (default value is false)
boolean	isAllowUnmatchedMessages()	Should the event handler allow unmatched Message.getPayload()? If true then an unmatched Message.getPayload() is ignored, if false (the default value) then an unmatched event will cause handleUnmatchedMessage(Message) will throw an IllegalArgumentException
PatternMatchingMessageHandler	removeInterceptor(MessageHandlerInterceptor interceptor)
void	setAllowUnmatchedMessages(boolean allowUnmatchedMessages)	Should the event handler allow unmatched Message.getPayload()? If true then an unmatched Message.getPayload() is ignored, if false (the default value) then an unmatched event will cause handleUnmatchedMessage(Message) will throw an IllegalArgumentException

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.function.Consumer

andThen

Constructor Details

PatternMatchingMessageHandler

public PatternMatchingMessageHandler(Object invokeMessageHandlerMethodsOn)

Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e. methods annotated with @MessageHandler, on another object

Parameters:

invokeMessageHandlerMethodsOn - the object that contains the @MessageHandler annotated methods

PatternMatchingMessageHandler

public PatternMatchingMessageHandler(Object invokeMessageHandlerMethodsOn,
 List<MessageHandlerInterceptor> interceptors)

Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e. methods annotated with @MessageHandler, on another object

Parameters:

invokeMessageHandlerMethodsOn - the object that contains the @MessageHandler annotated methods

interceptors - message handler interceptors

PatternMatchingMessageHandler

public PatternMatchingMessageHandler()

Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e. methods annotated with @MessageHandler, on this concrete subclass of PatternMatchingMessageHandler

PatternMatchingMessageHandler

public PatternMatchingMessageHandler(List<MessageHandlerInterceptor> interceptors)

Create an PatternMatchingMessageHandler that can resolve and invoke message handler methods, i.e. methods annotated with @MessageHandler, on this concrete subclass of PatternMatchingMessageHandler

Method Details

addInterceptor

public PatternMatchingMessageHandler addInterceptor(MessageHandlerInterceptor interceptor)

removeInterceptor

public PatternMatchingMessageHandler removeInterceptor(MessageHandlerInterceptor interceptor)

isAllowUnmatchedMessages

public boolean isAllowUnmatchedMessages()

Should the event handler allow unmatched Message.getPayload()? If true then an unmatched Message.getPayload() is ignored, if false (the default value) then an unmatched event will cause handleUnmatchedMessage(Message) will throw an IllegalArgumentException

Returns:

should the event handler allow unmatched events

setAllowUnmatchedMessages

public void setAllowUnmatchedMessages(boolean allowUnmatchedMessages)

Should the event handler allow unmatched Message.getPayload()? If true then an unmatched Message.getPayload() is ignored, if false (the default value) then an unmatched event will cause handleUnmatchedMessage(Message) will throw an IllegalArgumentException

Parameters:

allowUnmatchedMessages - should the event handler allow unmatched Message.getPayload()

allowUnmatchedMessages

public void allowUnmatchedMessages()

Should the event handler allow unmatched Message.getPayload()? If true then an unmatched Message.getPayload() is ignored, if false (the default value) then an unmatched event will cause handleUnmatchedMessage(Message) will throw an IllegalArgumentException

See Also:

• setAllowUnmatchedMessages(boolean)

accept

public void accept(Message message)

Specified by:

accept in interface Consumer<Message>

handleUnmatchedMessage

protected void handleUnmatchedMessage(Message message)

Override this method to provide custom handling for Message's who's Message.getPayload() aren't matched
Default behaviour is to throw an IllegalArgumentException unless isAllowUnmatchedMessages() is set to true (default value is false)

Parameters:

message - the unmatched message

handlesMessageWithPayload

public boolean handlesMessageWithPayload(Class<?> payloadType)

Check amongst all the MessageHandler annotated methods and check if there's a method that matches (i.e. is type compatible) with the payloadType.

Parameters:

payloadType - the Message.getPayload()'s concrete type

Returns:

true if there's a MessageHandler annotated method that accepts a Message with a Message.getPayload() of the given payloadType, otherwise false