codewars051: Single Word Pig Latin

Instructions:

Single Word Pig Latin

Solution:

public class PigLatin{
 
   public String translate(String str){

		if (str == null || str.equals("") || !str.matches("[a-zA-Z]+")) {
			return null;
		}
		StringBuilder sb = new StringBuilder(str.toLowerCase());
		boolean startWithVowel = false;
		int index = -1;
		for (int i = 0; i < sb.length(); i++) {
			char c = sb.charAt(i);
			if ("aeiou".indexOf((int) c) != -1) {
				if (i == 0) {
					startWithVowel = true;
				}
				index = i;
				break;

			}

		}
		for (int i = 0; i < index; i++) {
			sb.append(sb.charAt(i));
		}
		if (index != -1 && !startWithVowel) {
			sb.delete(0, index);
		}

		return startWithVowel ? sb.toString() + "way" : sb.toString() + "ay";
	
   }
   
 }

Example Tests:

import static org.junit.Assert.*;

import org.junit.Before;
import org.junit.Test;


public class TestPigLatin {

	private PigLatin p;

	@Before
	public void setUp() throws Exception {
		p = new PigLatin();
		
	}

	@Test
	public void testMap() {
		assertEquals("apmay", p.translate("map"));
	}
	
	@Test
	public void testegg() {
		assertEquals("eggway", p.translate("egg"));
	}
  
  @Test
	public void testspaghetti() {
		assertEquals("aghettispay", p.translate("spaghetti"));
	}
}