testing - How do I properly write out a JUnit test for a method that counts how many e's are in a string? -

here method have defined supposed accept string input , should return number of times char 'e' occurs int:

public int count_e(string input){     int count = 0;     (int = 0;i<input.length();i++){         char e = 'e';         if (input.charat(i)==e){             count=count+1;             i++;             return count;         }         else{             count=count+1;             i++;         }     }     return count; } 

}

i trying write junit test see if can input string method , return correct number of e's. below test, , @ moment keep getting error saying method count_e undefined type string.

can tell me why coming undefined?

@test public void testcount_e() {     string input= "isabelle";     int expected= 2;     int actual=input.count_e();     asserttrue("there many e's in string.",expected==actual); } 

}

you failed pass anything count_e method!

how like:

@test public void testcount_e() {     string input = "isabelle";     int expected = 2;     int actual = count_e(input);     assert.assertequal("there many e's in string.", expected, actual); } 

for unit test, shorten to:

@test public void testcount_e() {     assert.assertequal("there many e's in string.", count_e("isabelle"), 2); }