Pig Latin Translator

import java.util.*;

public class Main {

    /**
     *This program takes a string given by the user and  converts it to pig latin
     */
    public static void main(String[] args) {
        System.out.println("Please insert a sentence to be translated"); //asks the user for input
        Scanner scan = new Scanner(System.in);
        String original = scan.nextLine();

        String translation = translateSentence(original); //translates it using a function

        System.out.println(translation); //prints the result
    }

    /**
     * This translates a whole sentence by using translateWord
     * @param str - user input
     * @return result, translated sentence
     */
    public static String translateSentence(String str){
        int lastSpace = 0;
        String result = "";

        for(int x = 0; x < str.length(); x++){
            if(str.charAt(x) == ' '){ //separates words based on spaces
                String word = str.substring(lastSpace, x);
                String translation = translateWord(word);

                result = result + translation + " "; //adds translated word to the sentence

                lastSpace = x + 1;
            }else if(x == str.length() - 1){ //last word in the string
                String word = str.substring(lastSpace, x + 1);
                String translation = translateWord(word);

                result = result + translation + " "; //adds translated word to the sentence

                lastSpace = x + 1;
            }
        }

        return result;
    }

    /**
     * Translates a single word
     * @param str - the word to be translated
     * @return result - translated string
     */
    public static String translateWord(String str){
        String result;
        String endPart;

        for(int x = 0; x < str.length(); x++){ //goes through the string looking for vowels
            if(isVowel(str.charAt(x))){
                endPart = str.substring(0, x); //if there is a vowel, that's the limit
                result = str.substring(x);

                endPart = endPart + "ay";      //add the part before the vowel with an "ay" to the end
                result = result + "-" + endPart;

                return result;
            }
        }

        //if there isn't a vowel, check for "y"
        for(int x = 0; x < str.length(); x++){
            if(str.charAt(x) == 'y'||str.charAt(x) == 'Y'){
                endPart = str.substring(0, x);
                result = str.substring(x);

                endPart = endPart + "ay";
                result = result + "-" + endPart;

                return result;
            }
        }

        //if there aren't any vowels or "y", just add "-ay"
        result = str + "-ay";
        return result;
    }

    /**
     * Returns whether a character is a vowel
     * @param b the character to be analyzed
     * @return if it is a vowel
     */
    public static boolean isVowel(char b){
        if(b == 'a'||b == 'e'||b == 'i'||b == 'o'||b == 'u'||b == 'A'||b == 'E'||b == 'I'||b == 'O'||b == 'U'){
            return true;
        }else{
            return false;
        }
    }

}