Question

In below code I am trying to do substring based on start and end index,But in end of the string.System is throwing ArrayIndexOutOfBoundsException. Please let me know, how to resolve this issue.

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int initlength = 20;
        int start = 0;
        String s = "Some people confuse acceptance with apathy, but there's all "+
"the difference in the world";
        int total=(int)Math.ceil((double)s.length()/(double)initlength);
        for (int i = 0; i < total; i++) {
            System.out.println("s length" + s.substring(start, initlength));
            start = initlength + 1;
            initlength = initlength + initlength;
            }
    }

Regards,

chaitu

Answer 1

step by step debug your code:

1. first time variables

   start=0;
initlength=0;
s="Some people confuse acceptance with apathy, but there's all the difference in the world";
total = 5.

2. s.length()/initlength = 4.

3. first substring will be from 0 to 20.
4. start = 21 and initlenght = 40
5. Second time in loop
6. s.length()/initlength = 2
7. substring from 21 to 40.
8. start = 41 and initlength = 80.
9. Third time in loop.
10. s.length()/initlength = 1 and i equal to 2 therefore loop will break and program execution will finish.

---

Based on your edit. Now it will loop for 5 times. And after 3rd time start = 81 and initlength = 160 which is out of range of string. For all the time total = 5.

---

If you want that it will get the remaining part the try this:

    int initlength = 20;
    int start = 0;
    String s = "Some people confuse acceptance with apathy, but there's all "
            + "the difference in the world";
    int total = (int) Math.ceil((double) s.length() / (double) initlength);
    for (int i = 0; i < total; i++) {
        if(initlength<s.length()){
            System.out.println("s length" + s.substring(start, initlength));
            start = initlength + 1;
            initlength = initlength + initlength;
        } else {
            initlength = s.length();
            System.out.println("s length" + s.substring(start, initlength));
            break;
        }
    }

output:-

s lengthSome people confuse 
s lengthcceptance with apat
s lengthy, but there's all the difference in th
s length world