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Thread: phone book

  1. #1
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    Default phone book

    I'm creating a programs for a project with the propuse to create a simple address book...
    I have a class PersonInfo from where I get the information from the user...such as name, last name and so on.
    After I have a class contact...here I would like to save the contact inside and array...be able to print the all list of contact or just one...and ask to the user if he want to add a new one.....and in this class I have a bunch of probelms. I'm just a beginner. Someone can give me some idea about what i do wrong ?

    import java.awt.List;
    import java.util.ArrayList;
     
    public class Contact
    {
       String name, lastname, address, email, phone, notes;
       Contact()
       {
          ArrayList list;
          list = new ArrayList(10000);
       }
     
       Contact(int size) 
       {
          ArrayList list = new ArrayList(size);
     
       }
       void insert() 
       {
          List.add();
          }
     
       void view() 
       {
          for (int i = 0; i < list.size(); i++) 
          {
             ((PersonInfo)list.get(i)).printEntry();
             }
          }
     
       public Contact(String name, String lastname, String address, String email,
             String phone, String notes)
       {
          this.name = name; 
          this.lastname = lastname; 
          this.address = address; 
          this.email = email; 
          this.phone = phone; 
          this.notes = notes; 
       } 
       public void printContact() 
       { 
          System.out.println("Name = " + name); 
          System.out.println("Last Name = " + lastname); 
          System.out.println("Address = " + address); 
          System.out.println("E-mail = " + email); 
          System.out.println("Phone = " + phone); 
          System.out.println("Note(s) = " + notes); 
       } 
       }
    Last edited by copeg; November 29th, 2010 at 12:56 PM.


  2. #2
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    Default Re: phone book

    Can you please define what you mean by 'bunch of problems'?

  3. #3
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    Default Re: phone book

    it doesn't compile.... if i take the array out...it works fine....i can enter one contact and print out the information of that contact....but when i start to work with the array ecc... the programs didn't work anymore

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    Default Re: phone book

    For future reference, please post all compiler errors. Right now, it seems you are trying to use variables outside their scope. You create Lists in the constructors which I am guessing should be instance variables, right now the loose scope after those methods exit so trying to reference them in another method won't compile.

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    Default Re: phone book

    sorry i didn't understand what should i do

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    Default Re: phone book

    Create list as an instance variable...click on the link (blue text) in my post above.

  7. #7
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    Default Re: phone book

    What is with this method:
    void insert() 
       {
          List.add();
          }

    I would guess you are not wanting to reference the List Object here.

    Apart from creating list as an instance variable (like you did with the name, lastname, address, email, phone, and notes Strings) you also need to be careful of case when you reference your variables. Remember that JAVA is case sensitive and that will a bunch of problems if you are not careful.
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    Default Re: phone book

    still....doesn't work....grgrgrgrgrg

  9. #9
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    Default Re: phone book

    i did
    inside class contact i delete all the part that i did with the array
    .....after the following method (print contact) i try to create a class contact list...in order to put the contact inside an array, print it and do other stuff... but i'm stuck it doesn't work

    public void printContact() 
       { 
          System.out.println("Name = " + name); 
          System.out.println("Last Name = " + lastname); 
          System.out.println("Address = " + address); 
          System.out.println("E-mail = " + email); 
          System.out.println("Phone = " + phone); 
          System.out.println("Note(s) = " + notes); 
       } 
     
       ContactList con = new ContactList();
     
       }
     
    public class ContactList 
    {
       public ContactList()
       {
          Contact c;
          Contact[] array_list;
       }
     
          public void List(Contact size) 
          {
             Contact[] array_list = new Contact[1000];
             }
     
       public void print() 
       {
     
          int c;
          Object array_list;
          for (c = 0; c < array_list; c++) 
          {
             System.out.println(array_list[c]);
          }
     
       }
     
       public void NewContact()
       {
     
       }
       public void sort()
       {
     
       }
     
       }
    Last edited by copeg; November 29th, 2010 at 04:44 PM.

  10. #10
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    Default Re: phone book

    For future reference, please use the code tags (read the signature of aussiemcgr for details on how to use the highlight tags).

    Once again, even if you have, re-read the link I posted above, because it contains information in there that you are missing. The code you posted is still creating local instances which lose scope after the method exits...
    public void list(Contact size){
             Contact[] array_list = new Contact[1000];
    }
    ...creates a new Contact array, which looses scope after the method exits, with the instance variable still not instantiated...
    public void list(Contact size){
             array_list = new Contact[1000];
    }
    ...instantiates the instance variable array_list as an array of type Contact and size 1000 (the values it contains still have yet to be instantiated however). Redefining the variable in the method just creates a local variable and does not use the instance variable

  11. #11
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    Default Re: phone book

    still...I think i did the change u suggested but it doesn't work

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    Default Re: phone book

    ummm...I don't get it...I'm trying to follow your suggestion but it doesn't work can u be more precise

  13. #13
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    Default Re: phone book

    ummm...I don't get it...I'm trying to follow your suggestion but it doesn't work can u be more precise

  14. #14
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    Default Re: phone book

    Define 'doesn't work', and please post any updated code you have thus far.

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    Default Re: phone book

    public void printContact() 
       { 
          System.out.println("Name = " + name); 
          System.out.println("Last Name = " + lastname); 
          System.out.println("Address = " + address); 
          System.out.println("E-mail = " + email); 
          System.out.println("Phone = " + phone); 
          System.out.println("Note(s) = " + notes); 
       } 
     
       ContactList con = new ContactList();
     
       }
     
    public class ContactList 
    {
       public ContactList()
       {
          Contact c;
          Contact[] array_list;
       }
     
          public void List(Contact size) 
          {
             Contact[] array_list = new Contact[1000];
             }
     
       public void print() 
       {
     
          int c;
          Object array_list;
          for (c = 0; c < array_list; c++) 
          {
             System.out.println(array_list[c]);
          }
     
       }
     
       public void NewContact()
       {
     
       }
       public void sort()
       {
     
       }
     
       }

    First things first: Is there a main somewhere? It would be easier to see all your code because the way its written itll just make contact c and your contact array and exit

    2)
    public void printContact() 
       { 
          System.out.println("Name = " + name); 
          System.out.println("Last Name = " + lastname); 
          System.out.println("Address = " + address); 
          System.out.println("E-mail = " + email); 
          System.out.println("Phone = " + phone); 
          System.out.println("Note(s) = " + notes); 
       } 
     
       ContactList con = new ContactList();
     
       }

    I spy two many close brackets? it seems possible

    public void List(Contact size) 
          {
             Contact[] array_list = new Contact[1000];
             }

    I'm thinking you don't mean to pass a Contact object named size?? I think you want to pass an int that you would put where the 1000 is.


       public void print() 
       {
     
          int c;
          Object array_list;
          for (c = 0; c < array_list; c++) 
          {
             System.out.println(array_list[c]);
          }
     
       }

    i don't think that println will work. or atleast they way you think it will. You would want to use your printContact method and pass the contact array_list[c] to it. Then do array_list[c].name etc...

    If you need more help, you can pm me. i threw together a quick program that'll do what i think your trying to do and i can give you more pieces of that if you need help.

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