asked on

Strings and Chars

I have a function I am trying to write:

public String ConvertTo83(String name) {
//Returns the Eight.Three filename version of name
String temp;
char result[] = new char[11];
temp = name.trim();
if (temp.length() > 0)
{
temp = temp.toUpperCase();
if(temp.indexOf(".") == -1){
for( int x = 0; x < temp.length(); x ++){
result[x] = temp.charAt(x);
}
for(int x = temp.length(); x < 11; x++)
result[x] = 0x20;
}
else
{
int y = temp.indexOf(".");
for( int z = 0; z < y; z++)
{
result[z] = temp.charAt(z);
}
//result[y] = '.';
for( int z = y; z < 11; z++)
{
result[z] = temp.charAt(z);
}
}
}
return result.toString();
}

However, the line :

result[x] = temp.charAt(x);

doesn't appear to be working. I am using Netbeans IDE to write this in, and trhe debugger shows the value of each of the chars of result to have the value '???'. This is obviously wrong. As I stp through the code, the line is executed without any errors, but the charAt(x) value is not placed in the result[z] position. I don't understand why thid would be happening??

please help
Thanks
Ashley

twobitadder

for( int x = 0; x < temp.length(); x ++){

should be for( int x = 0; x < (temp.length() -1); x ++){

remember that arrays start at 0 but you return the number of characters in the string using temp.length.

so if you return 5 for length of "hello"
you want to cycle through elements 0-4

You just overshoot by 1.

twobitadder

actually that's wrong sorry, ignore that.

ashleycoker

ASKER

it doesn;t even work on the first pass through. I just dont understand. It seems a simple operation.

twobitadder

Hi,
the problem is the line:

char result[] = new char[11];

you create a bounded array so your method will try and access as many characters as there are in the original string and assign those to the corresponding x position in your array.

However your array can only hold 11 chars so if the string is over 11 chars after trimming leading and trailing whitespace then you will try to write off the end of the array and throw a java.lang.ArrayIndexOutOfBoundsException.

Change result so it is initialised like:

char result[];

result = new char[temp.length()]

ASKER CERTIFIED SOLUTION

twobitadder

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

SOLUTION