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Re: checking for null Noob question
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Re: checking for null Noob question


  • Subject: Re: checking for null Noob question
  • From: Steve Peery <email@hidden>
  • Date: Sat, 31 Jul 2010 22:39:59 -0400

Just to avoid confusion and the NullPointerException, I would suggest this:

{
   if (this.dueDateType() == null) {
	return "";
   }
   else if (this.dueDateType().equals("N")) {
	return "";
   }
   return this.dueDateType();
}

or this:

{
   if (this.dueDateType() != null) {
      if (!this.dueDateType().equals("N")) {
         return this.dueDateType();
      }
   }
   return "";
}

Steve


On Jul 31, 2010, at 8:13 AM, Jérémy DE ROYER wrote:

> So the answer is :
> - "if the object is null, as, in the second test, your use the method 'equals' on this object (null) > NullPointerException"
>
> On the first test, as you first test if the object is null, you can't have a NullPointerException
>
> Hope this help,
>
> Jérémy
>
> Le 31 juil. 2010 à 14:09, Theodore Petrosky a écrit :
>
>> Yes... I was asking 'Why?' is there a NullPointerException with number 2...
>>
>> Ted
>>
>>
>> --- On Sat, 7/31/10, Jérémy DE ROYER <email@hidden> wrote:
>>
>>> From: Jérémy DE ROYER <email@hidden>
>>> Subject: Re: checking for null Noob question
>>> To: "Theodore Petrosky" <email@hidden>
>>> Cc: email@hidden
>>> Date: Saturday, July 31, 2010, 8:07 AM
>>> I won't do the second one because you
>>> could see a NullPointerException. Is it your question ?
>>>
>>> Jérémy
>>>
>>> Le 31 juil. 2010 à 14:05, Theodore Petrosky a écrit :
>>>
>>>>
>>>> Why does this work:
>>>>
>>>> public String dueDateTypeLetter() {
>>>>
>>>> if (this.dueDateType() == null ||
>>> this.dueDateType().equals("N")) {
>>>> return "";
>>>> }
>>>> return this.dueDateType();
>>>> }
>>>>
>>>> and this doesn't....
>>>>
>>>> public String dueDateTypeLetter() {
>>>>
>>>> if (this.dueDateType().equals("N") ||
>>> this.dueDateType() == null) {
>>>> return "";
>>>> }
>>>> return this.dueDateType();
>>>> }
>>>>
>>>> obviously the difference is the order of checking in
>>> the 'if' statement...
>>>>
>>>> I don't really care that I must check in a specific
>>> order... It just took me time to understand that the order
>>> was important.
>>>>
>>>> Ted
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
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>>>
>>
>>
>>
>
>
>
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References: 
 >Re: checking for null Noob question (From: Theodore Petrosky <email@hidden>)
 >Re: checking for null Noob question (From: Jérémy DE ROYER <email@hidden>)

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