Thread: What is wrong with this method?

This method is supposed to check if the inputed number is a number and not a letter and then complete the function. However, every time I try it always is saying the input is wrong.

For example:

If I type in "5 * 5"

it says Error Incorrect Input
Re-input your numbers:

when it shouldn't do anything. I can't figure it out.

My Code Is:

     public void multiply() throws IOException {       
        boolean valid = true;
        boolean valid1 = true;
        int i = 0;
        int k = 0;
        String string = input;
        String[] strings = string.split("\\*");
        String string1 = strings[0];
        String string2 = strings[1];
        for (valid = true; i < strings[0].length();) {
            if (strings[0].charAt(i) == '0'
                    || strings[0].charAt(i) == '1'
                    || strings[0].charAt(i) == '2'
                    || strings[0].charAt(i) == '3'
                    || strings[0].charAt(i) == '4'
                    || strings[0].charAt(i) == '5'
                    || strings[0].charAt(i) == '6'
                    || strings[0].charAt(i) == '7'
                    || strings[0].charAt(i) == '8'
                    || strings[0].charAt(i) == '9'
                    || strings[0].charAt(i) == '*') {
                valid = true;
            } else {
                valid = false;
            }
            i++;
        }
        for (valid1 = true; k < strings[1].length();) {
            if (strings[1].charAt(k) == '0'
                    || strings[1].charAt(k) == '1'
                    || strings[1].charAt(k) == '2'
                    || strings[1].charAt(k) == '3'
                    || strings[1].charAt(k) == '4'
                    || strings[1].charAt(k) == '5'
                    || strings[1].charAt(k) == '6'
                    || strings[1].charAt(k) == '7'
                    || strings[1].charAt(k) == '8'
                    || strings[1].charAt(k) == '9'
                    || strings[1].charAt(k) == '*') {
                valid1 = true;
 
            } else {
                valid1 = false;
            }
            k++;
 
 
             if (valid1 == true && valid == true) {
                     System.out.println("Multiply"); 
                  //Going to finish
                } else {
                    System.out.println("Error Incorrect Input");
                    System.out.println("Re-input your numbers:");
                    check();
                }
        }
    }

Are you checking the string for spaces?

Its cause your spaces. You split the first string into "5 ", and go through both characters. Space is not equal to a number so your valid is set to false. Then it goes to the next loop, and sets valid1 to false, then valid1 to true, and checks to see if valid and valid1 are both true.. yet valid is still false.