Java Programme to convert CaptialLetters - Ex: hello world and output is hELLO wORLD

 public class StringConversion {

    public static String display(String str){
        String words[]=str.split("\\s");
        String capitalizeWord="";
        for(String w:words){
            String first=w.substring(0,1);
            String afterfirst=w.substring(1);
            capitalizeWord+=first+afterfirst.toUpperCase()+" ";
        }
        return capitalizeWord.trim();
    }

    public static void main(String[] args) {
        System.out.println(display("hello world"));
    }
}

output: hELLO wORLD