CODEWITHSUNDEEP
javaswingloops
ismail_1
ismail_1

Reputation: 149

While loop JOptionPane issues

Ok - I know that I am fairly close to the solution but need a nudge in the right direction. I need the user to hit YES and the program to begin asking the question again.

After execution, I get the following errors

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 1 at java.lang.String.charAt(Unknown Source) at Vowel3.main(Vowel3.java:49)

// java class for Panel I/O
import javax.swing.JOptionPane;

// declaration of the class
public class Vowel33
{

    // declaration of main program
    public static void main(String[] args)
    {

    // objects used to store data
    String input_string = null;
    int a_count = 0;
    int e_count = 0;
    int i_count = 0;
    int o_count = 0;
    int u_count = 0;
    int i = 0;
    int yes = 0;

    // 1. display a descriptive message
    String display_message = "This program asks the user for a sentence,\n" 
        + "searches the sentence for all vowels,\n"
        + "and displays the number of times each"
        + "vowel appears in the sentence";
    JOptionPane.showMessageDialog(null, display_message, "Lab 3 Description", JOptionPane.INFORMATION_MESSAGE);



    // 4. visit each String posotion

     do{

        // 3. input the character string

        input_string = JOptionPane.showInputDialog("Enter the sentence to search");

        // 5.  if position i of String is a vowel
        // 6.  increase the appropriate vowel counter
        if (input_string.charAt(i) == 'a' || input_string.charAt(i) == 'A')
        a_count++;

        else if (input_string.charAt(i) == 'e' || input_string.charAt(i) == 'E')
        e_count++;

        else if (input_string.charAt(i) == 'i' || input_string.charAt(i) == 'I')
        i_count++;

        else if (input_string.charAt(i) == 'o' || input_string.charAt(i) == 'O')
        o_count++;

        else if (input_string.charAt(i) == 'u' || input_string.charAt(i) == 'U')
        u_count++;

        i++;

        String display_message1 = input_string                                      // 7. display the String
        + "\n\n" + "has " + input_string.length() + " characters.\n\n"          // 8. display the number of characters
        + "There are \n" 
        + a_count + " a's,\n"                                                   // 9. disaply the number of each vowel
        + e_count + " e's,\n"
        + i_count + " i's,\n"
        + o_count + " o's, and\n"
        + u_count + " u's.\n\n";

        JOptionPane.showMessageDialog(null, display_message1, "Lab 3 Description", JOptionPane.INFORMATION_MESSAGE);

        yes = JOptionPane.showConfirmDialog(null, "Would you like to enter another string?\n\n", "Extra Credit", JOptionPane.YES_NO_OPTION);

    }   while (i < input_string.length());

            if (i == input_string.length())
            {
                yes = JOptionPane.showConfirmDialog(null, "Would you like to enter another string?\n\n", "Extra Credit", JOptionPane.YES_NO_OPTION);
                if (yes == 1)
                {
                    input_string = JOptionPane.showInputDialog("Enter the sentence to search");
                }
            }






    } // end of main
} // end of the class

Upvotes: 0

Views: 467

Answers (1)

ryanlutgen
ryanlutgen

Reputation: 3041

In your code you have a condition where the loop can still be executed if yes is 0. Since yes is never redefined from what I can see, you basically have an infinite loop and your code will error out when i exits the bounds of your string's length.

Also not sure why you have two JOptionPanes at the bottom of the loop (which would execute x times where x = input_string.length())

Consider something like:

if(i == input_string.length()) {
    //ask the user if they want to enter another string
    if(the user selected yes){
        yes = 1;
        //instantiate again with new input_string
    }
}

Another note: Assuming you want to show a message asking if the user wants to enter another string once you've finished iterating through their first entry, it seems moot to have the yes variable and condition.

Upvotes: 1

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