Array must has length but i want without it

[Formula]

Hi all,i have Big problem mmm that the array must has the length but my program cann't be. Becase the array depend on the loop so i don't want to give a number like 20 or 100 .

I searched through my book and didn't found anything.

So in java i have to add number to my array,it work greet but i donn't want to do it.
Please Help.

import javax.swing.JOptionPane;

public class  ConvertDtoB{
	
	
  public static void main(String arg[]){
  	
   int ircounter=-1;
   int[] iarray=new int[20];
   int[] rarray=new int[20];
   
   float number;
   int asas,f1,r2;
   number=(int)Float.parseFloat(JOptionPane.showInputDialog("Enter number"));
   System.out.println("The binary of the following decimal number "+number+" is:");
   asas=(int)number;	
   
   int d2=2;
	while(d2==2)
	{
		f1=asas/2;
		r2=(int)asas-(f1*2);
		ircounter++;
		iarray[ircounter]=f1;
		rarray[ircounter]=r2;
		System.out.println(rarray[ircounter]);
		
		if(f1!=0){asas=f1;}else{break;}
	}
  }

}

I do it in php like this.

<?php
class d2b{
var $iarray=array();
var $rarray=array();

	function d2b($asas){
	$f1=$asas/2;
	$f1=intval($f1);
	$r2=($asas)-($f1*2);

	array_push($this->iarray,$f1);

//add value to the binary array
	array_push($this->rarray,$r2);
//if the reminder != 0 loop it
	 if($f1!=0){d2b::d2b($f1);}
	}

}
$D2b=new d2b(125);
print_r($D2b);
?>

[JosAH]

As you have found out already: arrays are kind of stupid: they have a fixed length and when you don't know that length in advance you're in trouble. Better use Lists or ArrayLists in particular; they give you all the 'aray' functionality and their length is adjusted on the fly; read their API documentation.

kind regards,

Jos

[Formula]

Thanks man .Even though I alredy use it in another language(i won't say which) ,but it didn't come to mined.
So I gave you this appliction for convert from decimal to binary it really usefull .Thanks again.

import java.util.*;
import javax.swing.JOptionPane;


public class  DecimalToBinary{
	
  public static void main(String arg[]){
  	
  	List iarray = new LinkedList();    
    iarray = new ArrayList();         
  	List rarray = new LinkedList();    
    rarray = new ArrayList();     
    int ircounter=-1;
    float number;
    int asas,f1,r2;
    number=(int)Float.parseFloat(JOptionPane.showInputDialog("Enter number"));
    System.out.println("The binary of the following decimal number "+number+" is:");
    asas=(int)number;	
   
   int d2=2;
	while(d2==2)
	{
		f1=asas/2;
		r2=(int)asas-(f1*2);
		
		ircounter++;
		
		iarray.add(ircounter,f1 );
		rarray.add(ircounter,r2 );
		
		System.out.println(rarray.get(ircounter)+":"+iarray.get(ircounter));
		
		if(f1!=0){asas=f1;}else{break;}
	}
	
  }

}

[JosAH]

Also have a look at the API of the several Integer.toStrin g(...) methods.

kind regards,

Jos