Java - Prueba sumativa 1 - Ejercicio 1 (Miercoles)

import java.util.Scanner;
public class cuenta_vocales_par{
public static void main (String args[]) {
    String frase;
    int V=0;
    int VT=0;
    int F=-1;
    while(V%2==0){
        VT = VT+V;
        frase = leeFrase();
        V = calculaVocales(frase);
        System.out.println("La frase contiene "+V+" vocales.");
        F++;
    }System.out.println("Vocales total encontradas: "+VT+". Cantidad de frases con cant. vocales pares: "+F);
}
public static String leeFrase(){
    Scanner tec = new Scanner(System.in);
    boolean Func = true;
    String frase = "";
    while (Func){
        System.out.print("Ingrese una frase: ");
        frase = tec.nextLine();
        Func=validaFrase(frase);
    }return frase;
}
public static boolean validaFrase(String f){
    for(int i = 0;i<f.length();i++){
        if(f.charAt(i)!=' '){
            return false;
        }
    }System.out.println("Error. Frase no valida.");
    return true;
}
public static int calculaVocales(String f){
    int cont = 0;
    for(int i = 0;i<f.length();i++){
        if(f.charAt(i)=='a'||f.charAt(i)=='e'||f.charAt(i)=='i'||f.charAt(i)=='o'||f.charAt(i)=='u'){
            cont++;
        }
    }return cont;
}
}