CODEWITHSUNDEEP
javaarrays
Ti J
Ti J

Reputation: 271

How to check if array[] has a null value in java?

I am reading a csv file. One of the requirements is to check if a certain column has a value or not. In this case I want to check the value in array[18]. However, I am getting 

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 18

Is there any other way to check the array index if it has a value or empty?

My code:

while ((sCurrentLine = br.readLine())!= null) { 

    String[] record = sCurrentLine.split(",");   

    if(record.length > 0){ // checking if the current line is not empty on the file
       if(record[18] != null){ // as per console, I am getting the error in this line
          String readDateRecord = record[18];
          // other processing here
       }
    }
}

Upvotes: 2

Views: 21135

Answers (6)

Akash Yellappa
Akash Yellappa

Reputation: 2314

If its an arrayList then check if it contains null

array.contains(null));

Upvotes: -2

xrcwrn
xrcwrn

Reputation: 5325

public static void main (String[] args) {
    Integer [] record = {1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1};
    for(int i = 0; i < record.length; i++)
        if(record[i] == null) {
            System.out.println(i+1 + " position is null");
        }
}

Upvotes: 0

mazhar islam
mazhar islam

Reputation: 5619

Look, according to JavaSE7:

ArrayIndexOutOfBoundsException thrown to indicate that an array has been accessed with an illegal index. (In your case) The index is greater than or equal to the size of the array.

Means, the index 18 is not legal for array record in your code. Moreover if the array record is null then you will get another exception called NullPointerException.

To overcome your problem, there are many solutions, one can be

//assuming that record is initialized 
if(record.length > 18){
      String readDateRecord = record[18];
      ...
   }

Upvotes: 2

Sunil
Sunil

Reputation: 447

Size is fixed in array after creation .if you get index beyond of size then it's generated ArrayIndexOutOfBoundException .So first you need to get the size of array then retrive the value from array

 int size=record.length;
 for(int i=0;i<size;i++)
  {
   if(record[i] != null){
     // other processing here
   }
 }

Declare an array with size “n” and access the n-th element. However, as we already mentioned, the indices of an array with size “n”, reside in the interval [0, n – 1].

Upvotes: 0

Razib
Razib

Reputation: 11163

You may try the following code snippet - 

int length = record.length;   
if( (n>0 && n<length-1) && record[n] != null ){

   String readDateRecord = record[n];
   //other processing here

}

Upvotes: 0

Subodh Joshi
Subodh Joshi

Reputation: 13492

Here one approach is this

Object array[] = new Object[18];
boolean isempty = true;
for (int i=0; i<arr.length; i++) {
  if (arr[i] != null) {
    isempty = false;
    break;
  }
}

Upvotes: 0

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