Help with switch case

This is my program, it will count all the spaces, all the letter a,e,s,t upper or lower cases but I'm having an error when compiling, it give me that one of my variable is not initialized.

Could someone take a look and tell me

import java.util.Scanner;

public class Count
{
  public static void main (String[] args)
  {
      String phrase;    // a string of characters
      int countBlank;   // the number of blanks (spaces) in the phrase 
      int length;       // the length of the phrase
      char ch;          // an individual character in the string
        int countA=0,countE=0,countS=0,countT=0;

    Scanner scan = new Scanner(System.in);
      // Print a program h开发者_JAVA技巧eader
      System.out.println ();
      System.out.println ("Character Counter");
      System.out.println ();

      // Read in a string and find its length
      System.out.print ("Enter a sentence or phrase: ");
      phrase = scan.nextLine();
      length = phrase.length();


        // Initialize counts
      countBlank = 0;

      // a for loop to go through the string character by character

        for (int i = 0; i < phrase.length(); i++)  
        {
    if(phrase.charAt(i) == ' ') countBlank++;
        }
    switch(ch) {
    case 'a':
    case 'A': countA++;
    break;

    case 'e':
    case 'E': countE++;
    break;

    case 's':
    case 'S': countS++;
    break;

    case 't':
    case 'T': countT++;
    break;

    }

      // Print the results
      System.out.println ();
      System.out.println ("Number of blank spaces: " + countBlank);
        System.out.println ("Number of a: " + countA);
        System.out.println ("Number of e: " + countE);
        System.out.println ("Number of s: " + countS);
        System.out.println ("Number of t: " + countT);
      System.out.println ();
    }

}

You write

switch(ch)

but the variable ch is never assigned a value.

You have "switch(ch)" but you never assigned it a value. You declared it using "char ch;" but that's not enough.

Maybe you want to do:

ch = phrase.charAt(i);

inside of your loop.

So your combined code can look like this:

import java.util.Scanner;

public class Count
{
  public static void main (String[] args)
  {
      String phrase;    // a string of characters
      int countBlank;   // the number of blanks (spaces) in the phrase
      int length;       // the length of the phrase
      char ch;          // an individual character in the string
        int countA=0,countE=0,countS=0,countT=0;

    Scanner scan = new Scanner(System.in);
      // Print a program header
      System.out.println ();
      System.out.println ("Character Counter");
      System.out.println ();

      // Read in a string and find its length
      System.out.print ("Enter a sentence or phrase: ");
      phrase = scan.nextLine();
      length = phrase.length();


        // Initialize counts
      countBlank = 0;

      // a for loop to go through the string character by character

        for (int i = 0; i < phrase.length(); i++)
        {
            if(phrase.charAt(i) == ' ') countBlank++;
            ch = phrase.charAt(i);

                switch(ch) {
                    case 'a':
                    case 'A': countA++;
                    break;

                    case 'e':
                    case 'E': countE++;
                    break;

                    case 's':
                    case 'S': countS++;
                    break;

                    case 't':
                    case 'T': countT++;
                    break;
                }
        }


      // Print the results
      System.out.println ();
      System.out.println ("Number of blank spaces: " + countBlank);
        System.out.println ("Number of a: " + countA);
        System.out.println ("Number of e: " + countE);
        System.out.println ("Number of s: " + countS);
        System.out.println ("Number of t: " + countT);
      System.out.println ();
    }

}

There are two issues: first the current character is never assigned to ch and second the switch statement is not inside for your for loop.

change Ur for statement like this , the switch must be included in the for , and the ch should be initialized to be the i-th character .

 for (int i = 0; i < phrase.length(); i++)  
                {
                if(phrase.charAt(i) == ' ')
                    {
                        countBlank++;
                    }
                ch = phrase.charAt(i);

                    switch(ch)
                    {
                        case 'a':
                        case 'A': countA++;
                        break;

                        case 'e':
                        case 'E': countE++;
                        break;

                        case 's':
                        case 'S': countS++;
                        break;

                        case 't':
                        case 'T': countT++;
                        break;

                    }
                }