Java string - compare charAt() and index operator [] -

i wonder whether slower use .charat() convert string variable s char[] a array , access via a[i] instead of s.charat(i) ?

let's working on problem has lots of operator on each character within string.

the implementation of string#charat(int index) oracle's java 7:

public char charat(int index) {     if ((index < 0) || (index >= value.length)) {         throw new stringindexoutofboundsexception(index);     }     return value[index]; } 

it's little safer check, it's exact same behavior.

it slower return char[]

public char[] tochararray() {     // cannot use arrays.copyof because of class initialization order issues     char result[] = new char[value.length];     system.arraycopy(value, 0, result, 0, value.length);     return result; } 

since have copy first.