Cannot convert String to int in Java

Question

In my program I need to convert a String to Int.

 String str = new String(request.getData());
 String [] setting = str.split(" "); 
 String bs = setting[1];

The value of bs is 1024, I use System.out.println to test it, and it displays on the screen with "1024".

But when I use

 int blockSize = Integer.parseInt(bs); 

it will return an exception point to the line of Integer.parseInt :

Exception in thread "main" java.lang.NumberFormatException: For input string: "1024"
 at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
 at java.lang.Integer.parseInt(Integer.java:458)
 at java.lang.Integer.valueOf(Integer.java:554)

Can someone help me to solve it? Thanks.

• lxcky: Are you sure bs contains 1024, because if so, then you shouldn't be getting any problem.
• lxcky: @darknight, I don't think it's an issue of excessive whitespace since he's using a space as a delimiter.
• Rustam: i think your bs contains string value not a integer that's why this error. make sure setting[postion] is an integer value. i mean like "somevalue".
• T.J. Crowder: @jacobbb - I suspect you have invisible characters in there. bs.length() would probably be helpful, and possibly even a loop over the characters outputting their character code: for (char ch : bs.toCharArray() ) { System.out.println(Integer.toHexString(ch)); }
• enrico.bacis: I think the issue is with some unicode hidden character. Test the length of the string and check if it is really 4.

Answer 1

I suspect you have some hidden unicode character in the string bs, you can remove the non-digits with:

bs = bs.replaceAll("\\D", "");
int blockSize = Integer.parseInt(bs);

The code above will also convert the string "1a2" to 12, but that doesn't seem your case.

• jacobbb: I tried bs.length(), the return value is 1019... and I used "bs = bs.replaceAll("\\D", "");" , problem solved, thanks.
• jacobbb: yeah..1019..idk why, the array setting[] is i sending from datagramSocket, is there sth to do with this?

Answer 2

try this code:

 String bs = setting[1].trim().toString();

Answer 3

 while( (!bs.matches("\\d+")) && (bs.length > 1)) 
 {
 bs = bs.substring(1);
 }
 if (bs.matches("\\d+")
 {
 int blockSize = Integer.parseInt(bs);
 }
 else
 {
 int blockSize = -1;
 }
 /* !! Then, check for "-1" in your application of 
 block size #runtime_exception_prevention */

This will continue to remove the offensive non digit bits down to 1, as necessary, until a digit is found or only one character remains in the string. The second check prevents the exception and returns a flagged value. Checking for this flagged value will intercept runtime exceptions. NB: I wrote this code in the comment block, please forgive any minor errors, I will gladly correct.