topic Re: [resolved] Null pointer exception - tMap in Talend Studio

[resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 06:19:22 GMT

Hi everyone,
I am facing this error (c.f screenshot) for a while now. Usually Google is my friend, but not today.
Thank you for your advice,

EDIT :
I think the error comes from the absence of a null test. Therefore I tried this 3 kind of test but none works.

(String)row7.selling_price.equals(null))?0:row7.selling_price

(row7.selling_price.toString().equals(null))?0:row7.selling_price

(row7.selling_price == null)?0:row7.selling_price

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 07:11:44 GMT

Hi,
There is null pointer exception in your tMap component.
You need to handle the null value. Is your row7.selling_priceP" Integer" data type? If so, please parse Int to String firstly and then
row7.selling_priceP)==null|| row7.selling_priceP .isEmpty())? value if it is null:do your further processing
Best regards
Sabrina

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 08:08:39 GMT

Hi xdshi,
What do you mean by " parse Int to String"
How can I do that and where ?
Thx,

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 08:33:54 GMT

Hi,
Please take a look at the attached screenshots.
Or you can use String.valueof in your expression, such as, String.valueOf(row1.newColumn)==null||(String.valueOf(row1.newColumn).isEmpty()
Best regards
Sabrina

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 08:49:02 GMT

The following code doesn't work (cf. screenshot) 😕
(String.valueOf(row8.payment_date)==null||String.valueOf(row8.payment_date).isEmpty())?false:true
I mean I get a "true" while I should get a "false" since row8.payment_date = null

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 09:07:34 GMT

Hi,
The ternary operation in tMap should be:
Condition?value if true: value if false
Best regards
Sabrina

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 09:24:53 GMT

My code is respecting the format.

My destination_field is a boolean.

(String.valueOf(row8.payment_date)==null||String.valueOf(row8.payment_date).isEmpty())?false:true

IF row8.payment_date is null or empty
destination_field = false
ELSE
destination_field = true

I face the same issue with a destination_field as a String and this code.


(String.valueOf(row8.payment_date)==null||String.valueOf(row8.payment_date).isEmpty())  ? "NULL OR EMPTY" : "NOT NULL AND NOT EMPTY"

I also tried to use the following code but it doesn't work neither.


(Relational.ISNULL(row8.payment_date)?false:true

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 09:55:21 GMT

Hi,
What's the actual result you are facing? Is it still null pointer exception in tMap? Have you tried to check "Code" tab to see if there is any compile error?
Best regards
Sabrina

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 10:19:06 GMT

I am still looking for the right code to use in order to check if my Date field is null or not.
As you can see on the screenshot below this code doesn't give me the right output value.
Since the value of payment_date=null, that means that the condition is true then I should get the value right after the '?' which is in my case false.
We can clearly see on the screenshot I get a true

(String.valueOf(row8.payment_date)==null||String.valueOf(row8.payment_date).isEmpty())?false:true

Thx a lot for helping me on that issue

Re: [resolved] Null pointer exception - tMap

Anonymous — Thu, 12 Nov 2015 12:33:55 GMT

Why are you using "String.valueOf"? It is that which is causing you problems. To check to see if an object is null, all you need to do is use "==null". You also won't get an empty date if the object is a Date. So your check should be similar to below I believe....

row8.payment_date==null ? false:true

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 01:59:22 GMT

Hi rhall_2.0,
I tried your solution before and as you can see on the screenshot below, it doesn't work neither 😕
Thx anyway.

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 02:34:39 GMT

Just to summarize, please find below all the codes I already tried and that lead either to an ERROR or either to the wrong VALUE
WRONG VALUE Relational.ISNULL(row8.payment_date)?false:true
WRONG VALUE row8.payment_date==null?false:true
WRONG VALUE row8.payment_date.equals(null)?false:true
ERROR row8.payment_date.isEmpty()?false:true
ERROR row8.payment_date==""?false:true
WRONG VALUE String.valueOf(row8.payment_date)==null?false:true
WRONG VALUE String.valueOf(row8.payment_date).equals(null)?false:true
WRONG VALUE String.valueOf(row8.payment_date).isEmpty()?false:true
WRONG VALUE String.valueOf(row8.payment_date)==""?false:true
WRONG VALUE row8.payment_date.toString()==null?false:true
WRONG VALUE row8.payment_date.toString().equals(null)?false:true
WRONG VALUE row8.payment_date.toString().isEmpty()?false:true
ERROR row8.payment_date.toString()=""?false:true
ERROR (String)row8.payment_date==null?false:true
ERROR (String)row8.payment_date.equals(null)?false:true
ERROR (String)row8.payment_date.isEmpty()?false:true
ERROR (String)row8.payment_date==""?false:true
Thank you for your advice,

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 04:28:48 GMT

Hi,
Have you already tried like this?
(row8.payment_date.equals(""))?false:true
Regards, May T.

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 05:34:08 GMT

Hi May T,
Thank you for this solution I didn't think about, but still it's not working (screenshot below)

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 06:16:01 GMT

Hi,
Don't test with "Test" button of Expression Builder.
Can you please test by running the whole Job (with that code).
Regards, May T.

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 06:18:46 GMT

I finally find something working, but it's dirty
I don't get the null pointer exception error anymore.

((String.valueOf(row8.payment_date).equals("null"))
||
(String.valueOf(row8.payment_date).equals("NULL"))
||
(String.valueOf(row8.payment_date).isEmpty()))
?false
:true

Thanks to all of you,

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 06:25:02 GMT

May T, I tried to run the job with your code, but I got the null pointer exception again.
Since I am facing so many troubles, do you think I forgot to configure something in Talend?
Thx.

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 06:51:03 GMT

Hi,
I think it's not related with configuration.
I'm not sure but I think it's depend on Type(data type) of your components and data file.
Regards, May.

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 07:19:26 GMT

In MySQL, the field is recorded as DATE (with no parameters) and the values look like 'YYYY-MM-DD'
In Talend, inside the tMap, the field is identified as Date "dd-MM-yyyy"
=> So, I change the format in the tMap to "yyyy-MM-dd", but it doesn't change anything. I still got the error with the code below.

(row8.payment_date.equals(""))?false:true

Anyway, thank you for your help, it seems that I got no choice to keep my dirty solution

Re: [resolved] Null pointer exception - tMap

Anonymous — Fri, 13 Nov 2015 10:23:23 GMT

Is "payment_date" a Date or a String? I assumed it was a Date since I didn't see anywhere where it said otherwise. If it is a String, then it is entirely possible that null is being represented as a String of "null". This is an annoying "feature" of Talend with the help of Java. If you have a null String and you concatenate it with a populated String, the null will be converted to "null".
Demonstrated in the example below.....
String hello = "hello";
String nullValue = null;
String result = hello+nullValue;
System.out.println(result);
If you run that code you will get ....
"hellonull"
You need to be aware of this when working with Strings that may have gone through a similar process.