From 9c2c0ea6c21b79cd6538fc132607b17b478546a7 Mon Sep 17 00:00:00 2001 From: "hyunghwan.chung" Date: Wed, 22 Jun 2016 13:43:49 +0000 Subject: [PATCH] rewrote some exception and ensure implementation code --- stix/kernel/Apex.st | 8 +++ stix/kernel/Context.st | 121 ++++++++++++++++++----------------------- 2 files changed, 62 insertions(+), 67 deletions(-) diff --git a/stix/kernel/Apex.st b/stix/kernel/Apex.st index 149d8a4..3859c88 100644 --- a/stix/kernel/Apex.st +++ b/stix/kernel/Apex.st @@ -306,6 +306,14 @@ { ^false. } + + #method handleException: exception + { + ('### EXCEPTION NOT HANDLED #### ', exception class name, ' - ', exception messageText) dump. + ## TODO: debug the current process???? " +## TODO: ensure to execute ensure blocks as well.... + Processor activeProcess terminate. + } } diff --git a/stix/kernel/Context.st b/stix/kernel/Context.st index d199f0b..18242a5 100644 --- a/stix/kernel/Context.st +++ b/stix/kernel/Context.st @@ -1,6 +1,6 @@ #class Exception(Apex) { - #dcl signalContext handlerContext handlerBlock messageText. + #dcl signalContext handlerContext messageText. ## To be extended below. } @@ -28,6 +28,44 @@ { ^nil } + + #method findExceptionHandlerContext + { + | ctx | + ctx := self. + [ ctx isExceptionHandlerContext ifTrue: [^ctx]. + ctx := ctx sender. + ctx isNil ] whileFalse. + ^nil + } + + #method findExceptionHandlerBlock + { + ^nil + } + + #method handleException: exception + { + | excblk retval posact | + + ## position of the temporary variable 'active' in MethodContext>>on:do. + ## for this code to work, it must be the last temporary variable in the method. + posact := (self basicSize) - 1. + + excblk := self findExceptionHandlerBlock: (exception class). + (excblk isNil or: [(self basicAt: posact) not]) ifTrue: [ + ^self.sender findExceptionHandlerContext handleException: exception + ]. + + exception handlerContext: self. + + self basicAt: posact put: false. + [ retval := excblk value: exception ] ensure: [ + self basicAt: posact put: true + ]. + + ##self return: retval. + } } #class(#pointer) MethodContext(Context) @@ -351,23 +389,25 @@ #method on: anException do: anExceptionBlock { -" | handlerActive |" + | exception_active | -" handlerActive := true. -thisContext isExceptionHandlerContext dump. +"thisContext isExceptionHandlerContext dump. (thisContext basicSize) dump. (thisContext basicAt: 8) dump. ## this should be anException (thisContext basicAt: 9) dump. ## this should be anExceptionBlock (thisContext basicAt: 10) dump. ## this should be handlerActive 'on:do: ABOUT TO EVALUE THE RECEIVER BLOCK' dump." + exception_active := true. ^self value. } #method on: exc1 do: blk1 on: exc2 do: blk2 { + | active | + active := true. ^self value. } @@ -375,7 +415,6 @@ thisContext isExceptionHandlerContext dump. { | v | - "v := self on: Exception do: [:ex | aBlock value. ex pass ]." v := self value. aBlock value. ^v @@ -408,6 +447,11 @@ thisContext isExceptionHandlerContext dump. self new signal: text } + #method handlerContext: context + { + self.handlerContext := context. + } + #method messageText { ^self.messageText @@ -416,8 +460,7 @@ thisContext isExceptionHandlerContext dump. #method signal { self.signalContext := thisContext. - self findHandlerContextStartingFrom: self.signalContext. - self handleException. + ((thisContext sender) findExceptionHandlerContext) handleException: self. } #method signal: text @@ -429,14 +472,11 @@ thisContext isExceptionHandlerContext dump. #method pass { ## pass the exception to the outer context - self.signalContext notNil - ifTrue: [ ## it's signaled earlier - ## TODO: Should i change the signalContex to thisContext??? - self findHandlerContextStartingFrom: (self.handlerContext sender). - self handleException. - ] + ((self.handlerContext sender) findExceptionHandlerContext) handleException: self. } +" +TODO: implement these methods.... #method return: value { self.handlerContext notNil ifTrue: [ @@ -466,61 +506,8 @@ thisContext isExceptionHandlerContext dump. Processor return: self to: (self.signalContext sender). ] } +" - ## #################################################################### ## #################################################################### - #method handleException - { - self.handlerContext notNil - ifTrue: [ -##'RETURNING TO....' dump. -##self.handlerContext dump. -##self.handlerContext sender dump. -##' ............' dump. - - ## arrange to execute the hander block after having returned - ## to the sender of the exception handler context. - ## if handler block is evaluated before returning, an - ## exception raised in the handler block causes a kind of - ## a recursive call to here. - ##Processor return: (self.handlerBlock value: self) to: (self.handlerContext sender) - ## so use a different primitive method that evaluate the block - ## after having returned to the given context. - Processor returnTo: (self.handlerContext sender) andEval: (self.handlerBlock) with: self. - ] - ifFalse: [ - ('### EXCEPTION NOT HANDLED #### ', self class name, ' - ', self messageText) dump. - ## TODO: debug the current process???? " - Processor activeProcess terminate. - ]. - } - - #method findHandlerContextStartingFrom: aContext - { - ## Find exception handling context starting from a given context - | ctx | - - ctx := aContext. - [ ctx notNil ] whileTrue: [ -##ctx dump. - ##(ctx handles: self) ifTrue: [ ^ ctx ]. - (ctx isExceptionHandlerContext) ifTrue: [ - | blk | - blk := ctx findExceptionHandlerBlock: (self class). - (blk notNil) ifTrue: [ - self.handlerBlock := blk. - self.handlerContext := ctx. -##'-------------' dump. - ^ctx - ]. - ]. - ctx := ctx sender - ]. -##'-------------' dump. - ## no handler is found - self.handlerBlock := nil. - self.handlerContext := nil. - ^nil - } } #class NoSuchMessageException(Exception)