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Thread: Array Lists filling for loop

  1. #1
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    Default Array Lists filling for loop

    Hi I am having trouble with Array Lists. What should the for loop header be for filling Array Lists?
    I am trying to use an explicit value Constant Names in the condition.
    Any help would be greatly appreciated. Thank you.
    Here is my code.


    <       public class PersonTester
    {
     
      public static void main(String[] args)
      {
       PersonTester tester = new PersonTester();
       // ArrayList<Person> persons = new ArrayList<Person>(20);
       String ELEMENT = "";
     
        for (int i = 0;i<ELEMENT.length(); i++)
        {
          char gender = tester.getRandomGender();
          String fName = tester.getRandomFirstName(gender);
          String lName = tester.getRandomLastName();
          int age = tester.getRandomAge();
          ArrayList<Person> persons = new ArrayList<Person>(20);
          persons[i] = new Person(fName, lName, gender, age);
          persons.size();
     
          //ArrayList<Person>people = new ArrayList<Person>(fName, lName, gender, age);
          System.out.println(persons);
        }
      }
     
      private char getRandomGender()
      {
        return Math.random() > 0.5? 'f':'m';
      }
     
      private String getRandomFirstName(char gender)
      {
        String firstName = "";
     
        if (gender == 'f')
        {
          firstName = femaleFirstNames[SingleRandom.getInstance().
                                       nextInt(femaleFirstNames.length)];
        }
        else
        {
          firstName = maleFirstNames[SingleRandom.getInstance().
                                     nextInt(maleFirstNames.length)];
        }
        return firstName;
      }
     
      private String getRandomLastName()
      {
        return lastNames[SingleRandom.getInstance().nextInt(lastNames.length)];
      }
     
      private int getRandomAge()
      {
        return SingleRandom.getInstance().nextInt(99) + 1;
      }                                                                                                        >
    Last edited by rob17; March 12th, 2012 at 09:26 AM.


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Array Lists filling for loop

    for filling Array Lists?
    What is the source of data that is being stored in the ArrayList?
    That could determine what controls the looping.

    Please Edit your post and wrap your code with[code=java]<YOUR CODE HERE>[/code] to get highlighting

  3. #3
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    Default Re: Array Lists filling for loop

    Thank you for posting back to me. I really appreciate it.

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    Default Re: Array Lists filling for loop

    I am a new user how do I highlight my code when I re- edit it. Thank you.

  5. #5
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    Default Re: Array Lists filling for loop

    Edit your post and wrap your code with
    [code=java]
    <YOUR CODE HERE>
    [/code]
    to get highlighting

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    Default Re: Array Lists filling for loop

    Hey Norm I have not wrapped any code on this site before. I would Really appreciate it if you could tell me the
    step by step process on how to do it. Thank you.

  7. #7
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    Default Re: Array Lists filling for loop

    1)Edit your post
    2) put the following before your code
    [code=java]
    3) Put<YOUR CODE HERE>
    4)Add the following after the code
    [/code]

  8. #8
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    Default Re: Array Lists filling for loop

    Thank you Norm I think I wrapped the code properly. It should be easier to read.

  9. #9
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    Default Re: Array Lists filling for loop

    The loop should execute until the user is done entering data.
    Its up to you to determine when that is. For example:
    1) ask the user for the number of inputs he'll do and use that in a for statement
    2) tell the user to enter data for xx items then loop xx times
    3) have the user enter "DONE" or some thing to tell the program to exit the loop

  10. #10
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    Default Re: Array Lists filling for loop

    Thank you for the help I really appreciate it. I did not think of that approach using the for loop. That makes sense. Thank you so much.

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