Introduction :
In this Java programming tutorial, we will learn how to remove all vowels from a user input string. We will learn two different ways to solve this problem. The program will first ask the user to enter a string. After that it will remove all the vowels from the string using two different methods and print out the final string.
Java Program :
import java.util.Scanner;
/**
* Example class
*/
public class ExampleClass {
//utility method to print a string
static void print(String value) {
System.out.println(value);
}
public static void main(String[] args) {
//1
Scanner scanner = new Scanner(System.in);
//2
String userInput;
print("Enter a line : ");
userInput = scanner.nextLine();
//3
removeVowels(userInput);
removeVowels2(userInput);
}
static void removeVowels(String line) {
//4
String resultString = line.replaceAll("[aeiouAEIOU]", "");
print("Result string : " + resultString);
}
static void removeVowels2(String line) {
//5
String resultString = "";
String vowels = "AEIOUaeiou";
//6
for (int i = 0; i < line.length(); i++) {
if (!vowels.contains(String.valueOf(line.charAt(i)))) {
resultString += line.charAt(i);
}
}
//7
print("Result string : " + resultString);
}
}
Explanation :
The commented numbers in the above program denote the step numbers below :
-
Create one Scanner object to read the user input string.
-
Read the string and store it in userInput variable.
-
Remove the vowels from the string using two different methods: removeVowels and removeVowels2.Pass the user input string to these methods as an argument.
-
For the first method, to remove all the vowels we are using the removeAll function. The first argument [aeiouAEIOU] means if any character is found equal to any of the character of this list, replace it by an empty character.
-
For the second method, create one variable resultString to hold the final string. Create one more string variable vowels to hold the characters of the vowels.
-
Start one for loop and check each character of the string. Append each character to resultString if it is not a vowel, i.e. if it is not present in the vowel string.
-
resultString will hold the final result string. Print it out.
Sample Output :
Enter a line :
This is a dog
Result string : Ths s dg
Result string : Ths s dg
Enter a line :
Hello World
Result string : Hll Wrld
Result string : Hll Wrld