字符串最后一个单词的长度

import java.util.Scanner;public class Main{    public static void main(String[] args){        String str="";        Scanner sc = new Scanner(System.in);        while(sc.hasNext()){            str = sc.nextLine();            if(str == "" || "".equals(str)){                return ;            }else if(str.length() >= 5000){                return ;            }else {                String[] ch = str.split(" ");                System.out.println(ch[ch.length-1].length());            }        }    }}