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Thread: ARRAYLIST

  1. #1
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    Question ARRAYLIST

    Hi,
    I need to create a method which selects a random word from my array list at random...at the moment it prints out what is in the array list...

     
    public class Bank
     
    {   
       public static void main(String[] args)   
       {   
          String[] words = {"Garage", "Swindon", "Newspaper", "Chocoloate"};   
     
          List<String> wordList = Arrays.asList(words);   
     
          for (String e : wordList)   
          {   
             System.out.println(e);   
     
            }
     
    }


  2. #2
    Super Moderator helloworld922's Avatar
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    Default Re: ARRAYLIST

    You need to actually generate the random number and only print out the specific element.

    To generate a random number:
    Random Class

    To print out a specific element of an array list:
    System.out.println(myArrayList.get(index));

  3. #3
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    Default Re: ARRAYLIST

    It comes up with cannot find symbol variable index?

  4. #4
    Super Moderator helloworld922's Avatar
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    Default Re: ARRAYLIST

    You have to declare the variable and set it with the result you get from using the Random class.

  5. #5
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    Default Re: ARRAYLIST

    Further to helloworld922's contribution,

    Assuming 'generator' is an instance of

    java.util.Random

    int index = generator.nextInt( n ), where 'n' is the length of your arraylist.

    Then print out the arraylist element at the position, 'index'.

    I hope this helps.

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