String index out of range exception

[Avi Sridhar]

Hi All helpful people, I need to take your help here.

I have a String object and an integer array

For the length of the string, I am trying to do something like this. My code is as follows..

    
 
String test = " a long string"; //length is 60
int [] characterIntArray = new int[256];
for(int i=0;i<61;i++)
    characterIntArray[(int) new Character(characterIntArray.charAt(i))] = i; // Line 9
 

I keep getting

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 60
at java.lang.String.charAt(String.java:558)
at <CLASSNAME>.main(<CLASSNAME>.java:9)

Help would be greatly appreciated.

Thanks

[marc weber]

If the length of a String is 60, then what is charAt(60)?

Hint: The first char is charAt(0) -- not charAt(1).

[Avi Sridhar]

Originally posted by marc weber:
If the length of a String is 60, then what is charAt(60)?

Hint: The first char is charAt(0) -- not charAt(1).

Hi, Thanks for the reply. I am not quite understanding what you are saying here..

charAt(60) will be the last character in the string.

Please explain your point here

[Henry Wong]

charAt(60) will be the last character in the string.

Let's try this one again....

charAt(0) will be the first character in the string.
charAt(1) will be the second character in the string.
charAt(2) will be the third character in the string.

Work this all the way to charAt(60) please.

Henry

[Garrett Rowe]

The point marc is trying to make is that String indexes start at 0. Therefore for a nonempty String of length x, the first character is always at index 0, the last character is always at index (x - 1).

[marc weber]

Originally posted by Avi Sridhar:
...charAt(60) will be the last character in the string...

No.

The 1st char is not charAt(1). It is charAt(0).
The 2nd char is not charAt(2). It is charAt(1).
The 3rd char is not charAt(3). It is charAt(2).
And so on.

So if the String has 60 chars, the 60th char is not charAt(60).

[marc weber]

(Whoops... Posted before I saw Henry's and Garrett's responses. So it's redundant, but hopefully clear now.)
[ June 20, 2008: Message edited by: marc weber ]

[Rob Spoor]

And unlike C strings (char arrays), Java strings are NOT NULL terminated (\0).

[Avi Sridhar]

Originally posted by Rob Prime:
And unlike C strings (char arrays), Java strings are NOT NULL terminated (\0).

Thanks everyone for your thoughts. it really helped.

I am going to use this instead

 
for(int i=0;i<60;i++) 
 

and we will get 60 chars there.

[Paul Sisco]

Originally posted by Avi Sridhar:


Thanks everyone for your thoughts. it really helped.

I am going to use this instead

 
for(int i=0;i<60;i++) 
 

and we will get 60 chars there.

This isn't exactly about your question. Hopefully I am not out of place asking this...
Are you sure the string length will always be 60? you should probably use a variable for the string length in place of the number 60. This way you can handle any length string up to the limit of your int array.

[fred rosenberger]

is there a reason why you can't do something like this:

for (int i = 0; i < test.length(); i++)

[Avi Sridhar]

Originally posted by fred rosenberger:
is there a reason why you can't do something like this:

for (int i = 0; i < test.length(); i++)

Thanks for the reply. Will use that