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Java substring : string index out of range

Answer 1

+4 A:

You really need to check if the strings length is greater to or equal to 38

nullptr 2009-06-04 22:55:34

Answer 2

+3 A:

substring(0,38) means the String has to be 38 characters or longer. If not, the "String index is out of range".

Apocalisp 2009-06-04 22:56:41

Answer 3

A:

itemdescription is shorter than 38 chars

pugmarx 2009-06-04 22:58:04

Answer 4

+1 A:

if (itemdescription != null && itemdescription.length() > 0) {
    pstmt2.setString(3, itemdescription.substring(0, Math.min(itemdescription.length(), 38))); 
} else { 
    pstmt2.setString(3, "_"); 
}

JeeBee 2009-06-04 22:58:25

I'd be really interested in knowing what itemdescription.substring(0, itemdescription.length()) would return :)

pugmarx 2009-06-04 23:05:24

var itemdescription = new String("Hello, World!");alert( itemdescription.substring(0, itemdescription.length) );returns "Hello, World!".

tom 2009-06-04 23:18:33

He probably wanted to do *something* with it.

Tom Hawtin - tackline 2009-06-04 23:22:27

hmm, yes, should have had an upper bound there. that's midnight posting for you...

JeeBee 2009-06-04 23:23:10

Answer 5

+8 A:

I"m guessing i'm getting this error because the string is trying to substring a Null value. But wouldn't the ".length() > 0" part eliminate that issue?

No, calling itemdescription.length() when itemdescription is null would not generate a StringIndexOutOfBoundsException, but rather a NullPointerException since you would essentially be trying to call a method on null.

As others have indicated, StringIndexOutOfBoundsException indicates that itemdescription is not at least 38 characters long. You probably want to handle both conditions (I assuming you want to truncate):

final String value;
if (itemdescription == null || itemdescription.length() <= 0) {
    value = "_";
} else if (itemdescription.length() <= 38) {
    value = itemdescription;
} else { 
    value = itemdescription.substring(0, 38);
}
pstmt2.setString(3, value);

Might be a good place for a utility function if you do that a lot...

Bert F 2009-06-04 23:17:01

Answer 6

A:

I'm assuming your column is 38 characters in length, so you want to truncate itemdescription to fit within the database. a utility function like the following should do what you want:

/**
 * Truncates s to fit within len. If s is null, null is returned.
 **/
public String truncate(String s, int len) { 
  if (s == null) return null;
  return s.substring(Math.min(len, s.length()));
}

then you just call it like so:

String value = "_";
if (itemdescription != null && itemdescription.length() > 0) {
  value = truncate(itemdescription, 38);
}

pstmt2.setString(3, value);

Chris Gow 2009-06-04 23:37:29

Answer 7

+1 A:

I would recommend apache commons lang. A one-liner takes care of the problem.

pstmt2.setString(3, StringUtils.defaultIfEmpty(
    StringUtils.subString(itemdescription,0, 38), "_"));

Marcelo Morales 2009-06-05 11:46:13

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Java substring : string index out of range

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