current community

your communities

more stack exchange communities

Stack Exchange
tour help
stack overflow careers
Take the 2-minute tour ×
Stack Overflow is a question and answer site for professional and enthusiast programmers. It's 100% free, no registration required.
up vote 2 down vote favorite

I keep receiving a NullPointerException while trying to get a string from any array (that is encapsulated within a Vector). I cannot seem to stop the error from happening. It's got to be something simple, however I think that I have been looking at it for too long and I could sure use another set of eyes. Here is my code:

 Vector<Event> details = vector.get(i).getEvent();

 for (int x = 0; x < details.size(); x++) {
      Event eDetails = details.get(x);

      person = eDetails.getEventPerson();
      place = eDetails.getEventPlace()[0];
      time = eDetails.getEventTime()[0];

 }

So when I try to get the item at position 0 in the array (when x is 0) that is returned from eDetails.getEventTime, a NullPointerException is thrown.

Now, when x is 0 I happen to know that the array element at position 0 of the getEventTime() array is an empty string, but it is NOT a null value. When x is 1 or 2, etc. I can retrieve the time just fine.

The problem is that I will still receive the NullPointerException when I try to do things like the following:

 **System.out.println(eDetails.getEventTime.length);**

 or

 String result;

 **if(eDetails.getEventTime[0] == null){**
      result = "";
 } else {
      result = eDetails.getEventTime[0];
 }

Any ideas?

Thanks!

share|improve this question
1  
I assume you mean getEventTime()[0] in your second block of code? Also, you're not really showing how you populate your objects. –  Jeremy Heiler Nov 22 '10 at 19:20
    
@Jeremy It should be getEventTime()[0] as getEventTime[0] would not compile (a method is not an array). –  extraneon Nov 22 '10 at 19:42
    
@extraneon -- I know that, and that's why I assumed. I was just trying to clarify with the OP. But what if the OP had a public instance variable getEventTime, however unlikely? –  Jeremy Heiler Nov 22 '10 at 22:27

3 Answers 3

up vote 2 down vote accepted

Are you sure in your second example, it shouldn't be:

if(eDetails.getEventTime() == null)

Instead of:

if(eDetails.getEventTime[0] == null)

Are you making sure you leave the [0] off when you do the null check?

If the function eDetails.getEventTime() returns null, then you'll get a NullPointerException when you try to do eDetails.getEventTime()[0];

share|improve this answer
up vote 1 down vote

Seems that when you get details.get(0).getEventTime() the array returned is null.

share|improve this answer
    
Could also be details.get(0).getEventPlace() that returns null, as that also returns an array (or null). –  extraneon Nov 22 '10 at 19:43
up vote 0 down vote

The simplest way to figure this out is:

Vector<Event> details = vector.get(i).getEvent();

 for (int x = 0; x < details.size(); x++) {
      Event eDetails = details.get(x);
      if (eDetails == null) {
          throw new NullPointerException("eDetails on pos " + x + " is null");
      }

      person = eDetails.getEventPerson();
      Something[] places = Details.getEventPlace();
      if (places == null) {
          throw ....
      }
      place = eDetails.getEventPlace()[0];

      Something[] times =  eDetails.getEventTime();
      if (times == null) {
          throw ....
      }
      time = eDetails.getEventTime()[0];
 }

It may not look nice but at least it's informative.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.