com.sourceforge.jpatterns.patterns.bhv.chain
Interface IChainMessage

All Superinterfaces:

Cloneable, Serializable

public interface IChainMessage
extends Serializable, Cloneable

This interface is going to be used as the DTO between different actors of "chain of responsibility" patterns implemented here. It could be used at both "hierarchical" and "chainable" implementations of this patterns. todo: check this statement
It identifies all the necessary methods for working with the chain of responsibility.

• identifying the type of message
• allow to pass the input objects
• allows to check the output of chain

Also the important feature is it allows to identify the handlers/hierarchy items which added/extended/initialized the inputs and outputs. todo: check this statement

todo: what about rmi/ejb/jta/jms communication? COuld this message used here?? todo: why we need it cloneable??? todo: which other interfaces it should extend todo: think over forwards/includes at the chain handlers etc. $Author:: zmicer $

Method Summary

Object	getInputParam(String name) Get unout param by its name.
Object	getOutputInfo(String param) Get the info which was put to that IChainMessage object.
String	getStatus()
String	getType()
void	setType(String type) The type of message.

Method Detail

getType

String getType()

Returns:

the type of message. Can not be null (otherwise IllegalArgumentException would appear).

getStatus

String getStatus()

Returns:

returns the constant allowing us to determine the status of message (if it is under construction or was proceed by the certain handlers/items etc ) todo: check this statement, introduce constants + introduce configuration os the system to do it

setType

void setType(String type)
             throws IllegalStateException

The type of message. Can not be null (otherwise IllegalArgumentException would appear).
The method allowing us to setup the item of the message (in simply words to modify the state of object is intended just to be used at the initialization of the message). At the base class of this interface the status would be analyzed using the getStatus() method to understand if we could change the status.
So it would be allowed only if the message is mutatable (configuration of the system allows us to do it - e.g. some handler changing the type of the message during sending it to the another handler/item. todo: check this statement) or it is under construction (was not send and was not processed yet).

Throws:

IllegalStateException - in the case the message is not at the appropriate state to be set with the typ

getInputParam

Object getInputParam(String name)
                     throws UnsupportedOperationException

Get unout param by its name. todo: method allowing to determine inouts param by the id/items/handler could(shoul????) be added todo: should we allow to remove the input params?? system configuration??? todo: where input params could be changed - at the handlers/items/inner runners etc?? todo: permissions for reading/writing here???

Note: the configuration system of implementation may restrict the usage of this method (it is unpermissed)

Parameters:

name - name of the input param. Can not be null (otherwise IllegalArgumentException would appear).

Returns:

Object, some informatino which was put as input param

Throws:

UnsupportedOperationException - in the case the message could not return the input params

getOutputInfo

Object getOutputInfo(String param)
                     throws UnsupportedOperationException

Get the info which was put to that IChainMessage object. todo: all the todos of above mentioned method have power here.

Note: the configuration system of implementation may restrict the usage of this method (it is unpermissed)

Parameters:

param - the name of param using which the object should be obtained. Can not be null (otherwise IllegalArgumentException would appear).

Returns:

the Object, output result.

Throws:

UnsupportedOperationException - in the case the message could not return the input params