JAVA program to count the number of vowels, consonants, digits, white spaces & special characters in a given string

This JAVA program is to count the number of vowels, consonants, digits, white spaces & special characters in a given string.

For example, string “code 21” will have 2 consonants(c,d),2 vowels(o,e), 2 digits(2,1), 1 whitespace and 1 special character(;).

Logic

We just use a for loop and for each parameter we keep an if condition along with a counter for each parameter.

Dry Run of the Program

Take input string s. Let us take s=code 21;

Convert String str to charArray str[].

Find length of str[] using length method and store it in variable n;

1st iteration for(i=0;i<n;i++) i.e. for(i=0;0<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) false

else if((str[i]>=’a’&& str[i]<=’z’) || (str[i]>=’A’&& str[i]<=’Z’))  true str[0]=’c’

consonants++ hence consonants=1

2nd iteration for(i=1;i<n;i++) i.e. for(i=1;1<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) true as str[1]=’o’

vowels++; hence vowels=1

3rd iteration for(i=2;i<n;i++) i.e. for(i=2;2<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) false

else if((str[i]>=’a’&& str[i]<=’z’) || (str[i]>=’A’&& str[i]<=’Z’))  true as str[2]=’d’

consonants++ hence consonants=2

4th iteration for(i=3;i<n;i++) i.e. for(i=3;3<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) true as str[3]=’e’

vowels++ hence vowels=2

else if((str[i]>=’a’&& str[i]<=’z’) || (str[i]>=’A’&& str[i]<=’Z’))  false

5th iteration for(i=4;i<n;i++) i.e. for(i=4;4<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) false

else if((str[i]>=’a’&& str[i]<=’z’) || (str[i]>=’A’&& str[i]<=’Z’))  false

else if(str[i]>=’0′ && str[i]<=’9′) false

else if (str[i]==’ ‘) true as str[4]=’ ‘ 

spaces++ hence spaces=1

6th iteration for(i=5;i<n;i++) i.e. for(i=5;5<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) false

else if((str[i]>=’a’&& str[i]<=’z’) || (str[i]>=’A’&& str[i]<=’Z’))  false

else if(str[i]>=’0′ && str[i]<=’9′) true as str[5]=2

digits++ hence digits=1

7th iteration for(i=6;i<n;i++) i.e. for(i=6;6<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) false

else if((str[i]>=’a’&& str[i]<=’z’) || (str[i]>=’A’&& str[i]<=’Z’))  false

else if(str[i]>=’0′ && str[i]<=’9′) true as str[6]=1

digits++ hence digits=2

8th iteration for(i=7;i<n;i++) i.e. for(i=7;7<8;i++)

if(str[i]==’a’ || str[i]==’e’ || str[i]==’i’ ||str[i]==’o’ || str[i]==’u’ || str[i]==’A’ ||str[i]==’E’ || str[i]==’I’ || str[i]==’O’ ||str[i]==’U’) false

else if((str[i]>=’a’&& str[i]<=’z’) || (str[i]>=’A’&& str[i]<=’Z’))  false

else if(str[i]>=’0′ && str[i]<=’9′) false

else true as str[7]=’;’

specialCharacters++ hence specialCharacters=1

Hence output is consonants=2, vowels=2, digits=2, spaces=1, specialCharacters=1 for string code 21;

Program

import java.util.*;

class Count
{
	public static void main(String args[])
	{
		int i,vowels=0,consonants=0,digits=0,spaces=0,specialCharacters=0;
    		String s;
		Scanner sc = new Scanner(System.in);
		System.out.println("Enter sentence");
	 	s=sc.nextLine();
		char str[] = s.toCharArray();
		int n= str.length;
    		for(i=0;i<n;i++)
    		{
       	 		if(str[i]=='a' || str[i]=='e' || str[i]=='i' ||str[i]=='o' || str[i]=='u' || str[i]=='A' ||str[i]=='E' || str[i]=='I' || str[i]=='O' ||str[i]=='U')
        		{
           	 		vowels++;
        		}
        		else if((str[i]>='a'&& str[i]<='z') || (str[i]>='A'&& str[i]<='Z'))
        		{
            			consonants++;
        		}
        		else if(str[i]>='0' && str[i]<='9')
        		{
            			digits++;
        		}
  		       	else if (str[i]==' ')
        		{
                        	spaces++;
       	 		}
        		else
        		{	
	                	specialCharacters++;
        		}
    		}
    		System.out.println("Vowels = "+vowels);
    		System.out.println("Consonants = "+consonants);
    		System.out.println("Digits = "+digits);
    		System.out.println("White spaces = "+spaces);
    		System.out.println("Special characters = "+specialCharacters);
	}
}

Output