2009/7/13 Claus Ibsen <claus.ib...@gmail.com>: >> >> Reading between the lines; are you really just trying to make folks >> use (what is currently called) "getOut()" and never try mutate what is >> currently called getIn()? >> >> i.e. so by default the "OUT" property is defaulted to a copy of IN >> that folks can change/mutate. >> >> (what we call these 2 methods is a separate discussion, whether its >> "in,out" or "originalMessage,message" or whatever >> > > Hadrian and I had a chat today and we are clearing up some bits. > I am more on line with him now on the IN and OUT thing. > > So lets keep them. > > And use the time to fix the tiny bits such as the getOut() doing its > lazy creating a new empty message. > And whether its possible to let IN be immutable.
I think we're kinda mostly on the same page (though saying it in different ways). BTW I'm taking off my devils advocate hat now :)... What we're agreeing on I think is that; * getIn() should be immutable (when folks try to change it we can throw the exception and describe how getOut() should be used to change the message) - to prevent folks using the old code (which will require code changes). * having the original immutable message available is handy; but mostly folks should concentrate on the 'out' (current name today) * the out should be automatically populated with a clone of the IN (to avoid all that pain with checking if there's an out or an in, or the possible loss of headers etc. Internally we can use a CopyOnWrite facade to reduce the cost of potentially copying a message which is not actually mutated. Given that; I think we're mostly agreeing. However given the confusion of getIn() and getOut() I'm wondering if actually your previous idea of changing the api of exchange to have a getMessage() which returns the thing a processor should be changing; then having a getOriginalMessage() (which can be null if you are the first in the chain) might reduce the amount of confusion? i.e. after sleeping on it, I'm warming to the idea of renaming getIn() -> getOriginalMessage() and getOut() -> getMessage(). (Or maybe getInputMessage() for getIn()?) Thoughts? -- James ------- http://macstrac.blogspot.com/ Open Source Integration http://fusesource.com/
