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Thread: clearing StringBuilder

  1. #1
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    Default clearing StringBuilder

    I'm using StringBuilder since I don't know how many times something could be added to a string.

    Is there a way to clear out the StringBuilder? As you can see below, the first time the program runs it works fine, but if I decide to play again, it adds old string to new.

    Welcome to Thirty3
     
    Would you like to play (Y/Q)? y
     
    Your cards: four of Hearts, Eight of Spades, Seven of Spades,  (Total 19)
    Would you like another card (Y/N)? y
    Your cards:four of Hearts, Eight of Spades, Seven of Spades, Six of Diamonds,  (Total 25)
    Would you like another card (Y/N)? y
    Your cards:four of Hearts, Eight of Spades, Seven of Spades, Six of Diamonds, Eight of Spades,  (Total 33)
    Would you like another card (Y/N)? n
     
    The dealer drew: Seven of Spades, Three of Diamonds, Six of Hearts, Eight of Hearts, Queen of Hearts,  (Total 34)
     
    You  - Current Total - Wins - 0 Ties - 0 Loses - 0
     
    Would you like to play again (Y/Q)? y
     
    Your cards: Ten of Spades, four of Spades, Five of Hearts,  (Total 19)
    Would you like another card (Y/N)? y
     
    // this is where the problem is, it should be Ten of Spades, four of Spades, Five of Hearts, then something else
     
    Your cards:four of Hearts, Eight of Spades, Seven of Spades, Ten of Spades, four of Spades, Five of Hearts, Six of Diamonds, Eight of Spades, Five of Hearts,  (Total 24)
    Would you like another card (Y/N)? n
     
    The dealer drew: Ace of Hearts, Three of Spades, Ten of Spades, Three of Hearts,  (Total 27)
     
    You  - Current Total - Wins - 0 Ties - 0 Loses - 0
     
    Would you like to play again (Y/Q)? n


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    Default Re: clearing StringBuilder

    I'm using StringBuilder since I don't know how many times something could be added to a string.
    Interesting. Technically, String objects are immutable, so "changing" one actually creates a new one unless the new version already exists in the String pool.
    Is there a way to clear out the StringBuilder?
    Reinitialize it empty.

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    Default Re: clearing StringBuilder

    so far, I've tried

    StringBuilder.setLength(0);

    But it still adds on to the old string

    --- Update ---

    I sent you a PM

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    Default Re: clearing StringBuilder

    // reinitialize an existing StringBuilder object empty
    stringBuilder = new StringBuilder();

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    Default Re: clearing StringBuilder

    Is there a way to clear out the StringBuilder?
    ...or delete the contents of the StringBuilder, starting at index 0 and going up to its length

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    Default Re: clearing StringBuilder

    I tried

    new StringBuilder(), not working
    StringBuilder.replace(), also not working

    --- Update ---

    Quote Originally Posted by GregBrannon View Post
    // reinitialize an existing StringBuilder object empty
    stringBuilder = new StringBuilder();
    Not working for me for some reason!

    --- Update ---

    Quote Originally Posted by copeg View Post
    ...or delete the contents of the StringBuilder, starting at index 0 and going up to its length
    I tried that also, not working

    StringBuilder.delete(0, StringBuilder.length());

    --- Update ---

    Here's the part of the code I think where the problem is, I want everything to reset to start a new "game"

                if(playAgain.equalsIgnoreCase("y"))
                {
                    playerTotal = 0;
                    dealerTotal = 0;
                    playerPoints = 0;
                    dealerPoints = 0;
     
                    PSB.delete(0, PSB.length());
                }


    --- Update ---

    I've got it. I forgot to "clear" my for loop String. I made it to " " at the end.

    Thanks,

    Tony

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    Default Re: clearing StringBuilder

    "not working" provides zero information. Do you get an error? then copy and paste the EXACT error message. Do you get incorrect behaviour? Then describe what does happen and what should happen instead.
    Improving the world one idiot at a time!

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