java - How come this doesn't work [trying to print out a new sentence with all the constants] -

java - How come this doesn't work [trying to print out a new sentence with all the constants] -

import javax.swing.joptionpane; public class indexof { public static void main(string[] args) { string newsentance = ""; string sentance = joptionpane.showinputdialog("enter sentance"); string vowels = "aeiou"; int len = sentance.length(); (int = 0; >=len; i++) { if(vowels.indexof(sentance.touppercase().charat(i))>0) { newsentance+=sentance.charat(i); } } system.out.println(newsentance); } }

i getting no errors in netbeans yet still returns nil when printing newsentance .length working returns number correctly if printed

what else be?

modifying code

int = 0; < len; i++

and

vowels.indexof(sentance.touppercase().charat(i)) < 0

results in constants getting printed.

java string indexof