javastringreversing

basic Java coding question about reversing order of words for JAVA

I am looking for a way to reverse the word in java. This is my code and it occurs errors.

Can somebody explain why?

import java.util.Scanner;

public class Robot {

    public static void reverse(String text) {
        int leng = text.length();
        int i = 0;
        while (leng-i>=0){System.out.print(text.charAt(leng-i));
        i++;
        }
    }

    public static void main(String[] args) {
        Scanner reader = new Scanner(System.in);
        System.out.println("Type in your text: ");
        String text = reader.nextLine();
        System.out.print("In reverse order: ");
        reverse(text);
    }

}

I expected it to reverse the order of the word but it does not.

Solution

  • It should be

    int i = 1;

    Otherwise, you will be getting a StringIndexOutOfBoundsException since text.length() is never a valid index.

    To make it a bit shorter (and cooler), you might want to write

    System.out.print(text.charAt(leng - i++));

    Though, we usually do

    System.out.print(new StringBuilder(text).reverse());