Context variableSubclass:#JavaContext
	instanceVariableNames:'exArg byteCode constPool method monitor'
	classVariableNames:''
	poolDictionaries:''
	category:'Java-Support'
!


!JavaContext methodsFor:'ST context mimicri'!

arg1Index
    "the java stack contains the receiver in a non-static
     method, as slot 0. Therefore, the first arg is found at slot2
     if this is for a non-static method"

    self method isStatic ifTrue:[
	^ 1
    ].
    ^ 2
!

argAt:n
    "return the i'th argument (1..nArgs)"

    ^ self at:(self arg1Index - 1 + n)

    "Created: / 2.1.1998 / 17:54:13 / cg"
    "Modified: / 2.1.1998 / 21:39:30 / cg"
!

argAt:n put:value
    "change the i'th argument (1..nArgs)"

    ^ super argAt:(self arg1Index - 1 + n) put:value

    "Created: / 2.1.1998 / 17:54:34 / cg"
    "Modified: / 2.1.1998 / 21:35:19 / cg"
!

args
    "return an array filled with the arguments of this context"

    |n|

    n := self numArgs.
    n == 0 ifTrue:[
	"/ little optimization here - avoid creating empty containers
	^ #()
    ].

    ^ (Array new:n) replaceFrom:1 to:n with:self startingAt:(self arg1Index).

    "Created: / 2.1.1998 / 17:54:57 / cg"
    "Modified: / 2.1.1998 / 21:34:44 / cg"
!

argsAndVars
    "return an array filled with the arguments and variables of this context"

    |n|

    n := self numArgs + self numVars.
    n == 0 ifTrue:[
	"/ little optimization here - avoid creating empty containers
	^ #()
    ].
    ^ (Array new:n) replaceFrom:1 to:n with:self startingAt:(self arg1Index).

    "Created: / 2.1.1998 / 17:55:14 / cg"
    "Modified: / 13.1.1998 / 15:44:56 / cg"
!

lineNumber
    |nr pc|

    pc := self pc.

"/ 'ask line for pc:' print. pc printCR.
    pc isNil ifTrue:[
	nr := self lineNumberFromMethod.
	nr notNil ifTrue:[
	    ^ nr
	].
	" '-> 0 [a]' printCR. " 
	^0
    ].

    nr := self method lineNumberForPC:pc.
    nr isNil ifTrue:[
	nr := self lineNumberFromMethod.
	nr notNil ifTrue:[
	    ^ nr
	].
	" '-> 0 [b]' printCR. " 
	^ 0
    ].
"/ '-> ' print. nr printCR.
     ^ nr.

    "Created: / 1.5.1996 / 15:05:47 / cg"
    "Modified: / 15.1.1998 / 15:25:29 / cg"
!

lineNumberFromMethod
    |m|

    m := self method.
    m notNil ifTrue:[
	^ m lineNumber
    ].
    ^ nil

    "Created: / 4.1.1998 / 23:34:45 / cg"
    "Modified: / 4.1.1998 / 23:35:55 / cg"
!

method
    "the method may be found in the interpreter temps ..."

    (method isKindOf:JavaMethod) ifTrue:[^ method].
    ^ super method

    "Created: / 1.5.1996 / 15:03:43 / cg"
    "Modified: / 16.10.1998 / 01:22:12 / cg"
!

methodHome
    ^ self
!

numArgs
    "return the number of args.
     Redefined since Java keeps the receiver of a non-static method
     at local slot 1."

    |n|

    n := super numArgs.
    self method isStatic ifFalse:[
	n := n - 1
    ].
    ^ n

    "Created: / 2.1.1998 / 22:21:24 / cg"
!

numTemps
    "return the number of temporary variables of the Method.
     Redefined since Java keeps the receiver of a non-static method
     at local slot 1."

    |n|

    n := self size - super numVars - super numArgs.
    ^ n

    "Created: / 13.1.1998 / 16:52:32 / cg"
    "Modified: / 13.1.1998 / 17:23:27 / cg"
!

numVars
    "return the number of locals.
     Redefined since Java keeps the receiver of a non-static method
     at local slot 0 and holds the args as locals."

    |n|

    n := super numVars.
    ^ n - self numArgs

    "Created: / 13.1.1998 / 17:03:08 / cg"
    "Modified: / 13.1.1998 / 17:25:16 / cg"
!

pc
    lineNr isNil ifTrue:[^ nil].
    ^ super lineNumber

    "Created: / 4.1.1998 / 23:33:48 / cg"
!

selector
    "the selector can be extracted from the method.
     the method may be found in the interpreter temps ..."

    |s m|

    selector isNil ifTrue:[
	m := self method.
	m notNil ifTrue:[
	    ^ m name
	]
    ].
    ^ super selector

    "Modified: / 30.12.1997 / 17:22:06 / cg"
    "Created: / 30.12.1997 / 17:23:47 / cg"
!

setPC:newPC
    lineNr := newPC

    "Created: / 5.1.1998 / 00:09:02 / cg"
!

temporaries
    "return an array filled with the arguments and variables of this context"

    |n nSkipped|

    "/ the flas-numVars includes the receiver and args
    nSkipped := super numVars "self numArgs + self numVars".
    "/ but my context setup is args+numvars.
    nSkipped := super numArgs + super numVars.

    n := self size - nSkipped.
    n == 0 ifTrue:[
	"/ little optimization here - avaoid creating empty containers
	^ #()
    ].

    ^ (Array new:n) replaceFrom:1 to:n with:self startingAt:nSkipped+1.

    "Created: / 13.1.1998 / 15:44:12 / cg"
    "Modified: / 13.1.1998 / 17:22:54 / cg"
!

vars 
    "return an array filled with the local variables of this context"

    |nonVars mySize|

    mySize := self numVars.
    mySize == 0 ifTrue:[
	"/ little optimization here - avaoid creating empty containers
	^ #()
    ].
    nonVars := (self arg1Index-1) + self numArgs.
    ^ (Array new:mySize) replaceFrom:1 to:mySize with:self startingAt:nonVars+1

    "Created: / 13.1.1998 / 16:48:16 / cg"
! !

!JavaContext methodsFor:'exception handler support'!

exceptionArg:aJavaException
    exArg := aJavaException

    "Created: / 7.1.1998 / 21:36:56 / cg"
!

markForException
    "set the exception handler flag in the receiver.
     The JVM needs this to enter an exception handler instead of restarting
     from the beginning (when the context is restarted).
     - a highly internal mechanism and not for public use."

    flags := flags bitOr:16r08000000.

"/ %{  /* NOCONTEXT */
"/      __INST(flags) = (OBJ)((INT)__INST(flags) | __MASKSMALLINT(__JAVA_EX_PEND));
"/ %}

    "Modified: 13.12.1995 / 19:05:22 / cg"
! !

!JavaContext methodsFor:'printing & storing'!

receiverPrintString
    "return a string describing the receiver of the context" 

    |receiverClass receiverClassName newString implementorClass|

"/ %{
"/     /*
"/      * special handling for (invalid) free objects.
"/      * these only appear if some primitiveCode does not correctly use SEND macros,
"/      * which may lead to sends to free objects. In normal operation, this 'cannot' happen.
"/      */ 
"/     if (__isNonNilObject(__INST(receiver)) && (__qClass(__INST(receiver))==nil)) {
"/         receiverClassName = __MKSTRING("FreeObject");
"/     }
"/ %}.
    receiverClassName notNil ifTrue:[^ receiverClassName].

    receiverClass := receiver class.
    receiverClassName := receiverClass name.
    (receiverClass == SmallInteger) ifTrue:[
	newString := '(' , receiver printString , ') ' , receiverClassName
    ] ifFalse:[
	newString := receiverClassName
    ].

    "
     kludge to avoid slow search for containing class
    "
    (selector ~~ #doIt and:[selector ~~ #doIt:]) ifTrue:[
	implementorClass := self methodClass. 
    ].
    implementorClass notNil ifTrue: [
	(implementorClass ~~ receiverClass) ifTrue: [
	    newString := newString , '>>>',
			 implementorClass name printString
	]
    ] ifFalse:[
	self searchClass ~~ receiverClass ifTrue:[
	    newString := newString , '>>>' , self searchClass name
	].
"/        "
"/         kludge for doIt - these unbound methods are not
"/         found in the classes methodDictionary
"/        "
"/        (selector ~~ #doIt and:[selector ~~ #doIt:]) ifTrue:[
"/            newString := newString , '>>>**NONE**'
"/        ]
    ].

    ^ newString

! !

!JavaContext methodsFor:'queries'!

hasStackToShow
    "private interface to the debugger.
     Smalltalk contexts return false here - other language frames
     (i.e. Java frames) may want to show the evaluation stack"

    ^ true

    "Modified: / 13.5.1997 / 16:31:12 / cg"
    "Created: / 7.5.1998 / 01:23:57 / cg"
!

isJavaContext
    "return true, if this is a javaContext."

    ^ true

    "Created: / 8.5.1998 / 21:23:47 / cg"
!

stackFrame
    "private interface to the debugger."

    ^ (1 to:self size) collect:[:i | self at:i]

    "Created: / 7.5.1998 / 01:26:19 / cg"
! !

!JavaContext class methodsFor:'documentation'!

version
    ^ '$Header: /home/jv/Projects/SmalltalkX/repositories/cvs/stx/libjava/JavaContext.st,v 1.26 1998/11/10 00:23:19 cg Exp $'
! !