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Thread: all objects in array the same?

  1. #1
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    Default all objects in array the same?

    in this code:
    import java.util.*;
    import java.io.*;
     
    public class FinalProject
    {
      public static void main (String[] args)
      {
        Scanner in = new Scanner(System.in);
        System.out.println("how many pages do you want?");
        int pages = in.nextInt();
        Html[] site = new Html[pages];
        for(int i = 0; i < pages; i++)
        {
          if(i==0)
          {
            System.out.println("black box line");
            String blkBox = in.nextLine();
            System.out.println("what do want the site titled?");
            String title1 = in.nextLine();
            System.out.println("what do you want on the home page?");
            String content = in.nextLine();
            System.out.println("what image do you want behind the page?");
            String image = in.nextLine();
            boolean home = true;
            site[0] = new Html(title1, content, image, home);
            System.out.println("bong " + site[i].titleGet() + " " + i);
          }
          else if(i>0)
          {
            System.out.println("what do you want page " + i + " titled?");
            String title = in.nextLine();
            System.out.println("what do you want on page" + i + "?");
            String content = in.nextLine();
            System.out.println("what image do you want behind the page?");
            String image = in.nextLine();
            boolean home = false;
            site[i] = new Html(title, content, image, home); 
            System.out.println("bong " + site[0].titleGet() + " " + i);
            System.out.println("bong " + site[i].titleGet() + " " + i);
          }
          else
          {
            System.out.println("bing");
          }
        }
        for(int j = 0; j < pages; j++)
        {
          if(j == 0)
          {
            try {
              BufferedWriter out = new BufferedWriter(new FileWriter(site[0].titleGet() + ".html"));
              out.write(site[0].homeGet(pages, site[0].titleGet()));
              out.close();
              System.out.println("ding " + site[j].titleGet() + " " + j);
            } catch (IOException e) {
            }
          }
          else if(j > 0)
          {
            try {
              BufferedWriter out = new BufferedWriter(new FileWriter(site[0].titleGet() + j + ".html"));
              out.write(site[j].pageGet());
              out.close();
              System.out.println("ding " + site[j].titleGet() + " " + j);
            } catch (IOException e) {
            }
          }
          else
          {
          }
        }
      }
    }

    using this object:
    public class Html
    {
      static String title, content, image;
      static boolean home;
     
      public Html(String t, String c, String i, boolean h)
      {
        title = t;
        content = c;
        image = i;
        home = h;
      }
      public String titleGet()
      {
        return(title);
      }
      public String pageGet()
      {
        return("<html><head><title>" + title + "</title></head><body background=\"" + image + "\"><h1 align=\"center\" font color=\"#00FF00\">" + content + "</h1></body></html>");
      }
      public String homeGet(int pages, String title)
      {
        String index = "";
        for(int j = pages -1; j > 0; j--)
        {
          index = index + "<a  font color=\"#00FF00\" href=\"" + title + j + ".html\">" + "page" + j + "</a> <br />";
          System.out.println("dong " + j);
        }
         return("<html><head><title>" + title + "</title></head><body background=\"" + image + "\"><h1 align=\"center\" font color=\"#00FF00\">" + content + "</h1> <br />" + index + "</body></html>");
      }
    }


    all objects in the site array are writen over by the newest entry, why?

    thanks
    Last edited by abrohm; June 16th, 2011 at 08:17 PM.


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: all objects in array the same?

    Do you understand what static means when a variable is declared as static?
    There is only ONE copy for all instances of the class.

  3. #3
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    Default Re: all objects in array the same?

    C:\Users\Alex\programs\assingment one\task one\final>java FinalProject
    how many pages do you want?
    3
    black box line
    what do want the site titled?
    index
    what do you want on the home page?
    content test
    what image do you want behind the page?
    test.jpg
    bong index 0
    bong index 1
    what do you want page 1 titled?
    test one
    what do you want on page1?
    test content one
    what image do you want behind the page?
    test.jpg
    bong test one 1
    bong test one 1
    bong test one 2
    what do you want page 2 titled?
    test two
    what do you want on page2?
    test content two
    what image do you want behind the page?
    test.jpg
    bong test two 2
    bong test two 2
    dong 2
    dong 1
    ding test two 0
    ding test two 1
    ding test two 2

    note: the ding, dong ect lines where for troubleshooting purposes

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: all objects in array the same?

    What is the purpose of the last post?
    You need to add an explanation of what you have posted.

  5. #5
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    Default Re: all objects in array the same?

    that was the output from command line, the ding lines showing the fact that it is over writing previous entries, the top of each pair being title of site[0] and lower being that of site[i]

  6. #6
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    Default Re: all objects in array the same?

    You have already been given an explanation in the first post. What about that post did you not understand?

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    Default Re: all objects in array the same?

    Norm's telling you that by declaring the Html class variables 'static', you ensure they are shared by all instances of the class, instead of each instance having it's own variables.

    Incidentally, rather than have loops that do one thing for the first item and something different for all the others, it's simpler, clearer, and more efficient to handle the first item outside the loop, then enter the loop with a start value of 1 instead of 0.

    Just sayin'
    Last edited by dlorde; June 17th, 2011 at 11:24 AM.

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