GetSwizzled error in cache

Question

Question

D Sun · Mar 1, 2018

I keep seeing <INVALID OREF>zMypropertyGetSwizzled+3^myClass.2 in the error log. In my case, Myproperty is a property of myClass. And Myproperty points to the the object of other class in the system. This error happens to 2 properties in the same class, and they are both object properties. This error pops up occasionally, and make the debugging harder.

Anyone knows what the issues are?

TIA

Discussion (14)0

Log in or sign up to continue

Robert Cemper · Mar 1, 2018

you do

set ref=##class(myClass).%OpenId(id)

but you don't check if you really got an object. the id might be invalid
continue with

if '$isobject(ref) quit ""

0 0

Robert Cemper · Mar 1, 2018

the code causing the problem in MyClass.2.int looks most likely like this:

Set oid=$select(i%Myproperty="":"",1:$listbuild(i%Myproperty_""))

you are inside an ObjectMethod and miss the actual Object reference.
This happens when you try to access a property inside a Classmethod.
classic mistake:

ClassMethod MyMethod(1,2,3) as %Status { set x=..Myproperty }

correct use:

ClassMethod MyMethod(oref,1,2,3) as %Status { set x=oref.Myproperty }

0 0

score 0 · Answer 1 · 2018-03-01T15:30:00-05:00

Please post this line of code (Open myClass -> See other code -> zMypropertyGetSwizzled routine, third line) :

zMypropertyGetSwizzled+3^myClass.2

score 0 · Answer 2 · 2018-03-01T16:13:05-05:00

class myClass extends (%persisten)

{

Property Someproperty As %String;

...

Property Myproperty1 As OtherClass1;

Property Myproperty2 As OtherClass2;

... some more other property total 215 properties in this class

}

class OtherClass1 extends (%persisten)

{

Property OtherClass1Property As %String;

}

ClassMethod myfuct( id) As %String

{

set ref=##class(myClass).%OpenId(id)

set str="my return: "_ref.Myproperty1.OtherClass1Property

quit str

}

Above is a similar situation and codes. When myfuct is called, sometimes it throws a <INVALID OREF> zMypropertyGetSwizzled+3^myClass.2

myClass is a very busy table.

score 0 · Answer 3 · 2018-03-01T16:16:00-05:00

Eduard Lebedyuk · Mar 1, 2018

You need to press "View other code" button (or Ctrl+Shift+V) and post zMypropertyGetSwizzled routine.

0 0

score 0 · Answer 4 · 2018-03-01T16:36:00-05:00

zMypropertyGetSwizzled(%this) public {
If $zobjval(,/*i% Myproperty */163,0,3,163)="" Quit ""
Set oref=##class( OtherClass ).%Open($select($zobjval(,/*i%Myproperty*/163,0,3,163)="":"",1:$listbuild($zobjval(,/*i% Myproperty */163,0,3,163)_""))) If oref="" Quit ""
Set modstate=$zobjval(,0) Set $zobjval(,/*r%Myproperty*/164,0,3,164)=oref Set $zobjval(,0)=$e(modstate,1,$l(modstate)\2)_$e($zobjval(,0),$l(modstate)\2+1,*)
Quit oref }

score 0 · Answer 5 · 2018-03-01T16:17:20-05:00

D Sun · Mar 1, 2018

In the above sample, Myproperty can be Myproperty1 or Myproperty2. Any thoughts?

0 0

score 0 · Answer 6 · 2018-03-01T16:41:05-05:00

D Sun · Mar 1, 2018

It is valid in the db, just not getting it. Don't know why. I am new to this.

0 0

score 0 · Answer 7 · 2018-03-01T16:58:09-05:00

Robert Cemper · Mar 1, 2018

you need an oref in ref
and also in Myproperty1, ...
So you have to check both . see answer

0 0

score 0 · Answer 8 · 2018-03-01T17:11:13-05:00

Thanks! very Interesting find. I will try that tomorrow. GetSwizzled means getting object from memory or what? I don't quite understand this.

score 0 · Answer 9 · 2018-03-01T17:17:00-05:00

simplified you could translate it to "lazy loading" if not in memory

more: http://docs.intersystems.com/latest/csp/docbook/DocBook.UI.Page.cls?KEY=GOBJ_persobj_swizzling

score 0 · Answer 10 · 2018-03-01T16:20:10-05:00

Eduard Lebedyuk · Mar 1, 2018

It shouldn't compile at all.

OP please post

w $zv

0 0

score 0 · Answer 11 · 2018-03-01T16:53:39-05:00

Those codes are not real codes, just give an idea what is happening ( I can't post real codes). The real codes works fine until couple days ago I start seeing those errors.

the $zv returns:

Cache for UNIX (IBM AIX for System P5-64) 2010.2.4 (Build 802_1_17238) Tue Apr 4 2017 19:48:24 EDT

score 0 · Answer 12 · 2018-03-01T16:40:02-05:00

ClassMethod myfuct( id) As %String { set ref=##class(myClass).%OpenId(id)

If '$isobject(ref) quit "no object 1, no return" if '$isrobject(ref.Myproperty1) quit "no object 2, no return"

set str="my return: "_ref.Myproperty1.OtherClass1Property quit str }