Count Vowels from a String, Use Constructor

Write a Java Program to Count the Number of Vowels in a given string. Use Constructor, Instances and Method, if necessary. Do not use any parameter with Constructor.

Reference: 
1.  Course Book(The Complete Reference Java j2se) ; Page 118

2. http://c-programming-sourcecode.blogspot.com/2014/12/count-number-of-vowels.html?updated-min=2014-12-01T00:00:00-08:00&updated-max=2015-01-01T00:00:00-08:00&max-results=41

Java Source Code:

package vowel;
import java.util.Scanner;
class CountVowels
{
int count =0;
String str;
CountVowels()
{
str="Bangladesh" ;
}
void get()
{
for (int i = 0; i < str.length(); i++) {
char ch = str.charAt(i);
if (ch == 'a' || ch == 'e' || ch == 'i' ||
ch == 'o' || ch == 'u' || ch == 'A' ||
ch == 'E' || ch == 'I' || ch == 'O' ||
ch == 'U')
count++;

}
System.out.println("Enter String is " + str);
System.out.println("Number of vowel of "+str+ " is : " + count);
}
}

public class vowel{
public static void main(String[]args){
CountVowels vol = new CountVowels();
vol.get();
}
}