Changing an arrays size

[Ryan Perlman]

I am trying to change the arrays size if some condition is not met.
my user will input 20 numbers between 10 and 100 if one is a duplicate of the other don't add it to the array. here is the code I have. It won't add the duplicate number but it sets that array to zero instead I just want to eliminate that
The code

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class FirstArray extends JApplet
    implements ActionListener
{
    JLabel label = new JLabel("enter Integers's");
    JTextField inputText = new JTextField(10);
    JTextArea output = new JTextArea(10,15);
    JTextArea message = new JTextArea(4, 15);
    JScrollPane sp = new JScrollPane( output );
    JButton print = new JButton("Print Array");
    JButton reset = new JButton("Reset Array");
    int size = 20;
    int count = 0;
    final int[] input = new int[size];
    
    public void init()
    {
        Container c = getContentPane();
        c.setLayout(new FlowLayout());
        c.add(label);
        c.add(inputText);
        inputText.addActionListener(this);
        c.add(message);
        message.setEditable(false);
        c.add(sp);
        output.setEditable(false);
        c.add(print);
        print.addActionListener(new PrintAction ());
        c.add(reset);
        reset.addActionListener(new ResetAction ());           
    }
    
    public void actionPerformed(ActionEvent e)
    {
        String searchKey = e.getActionCommand();
        
        int num = Integer.parseInt(inputText.getText());
        
            if (num < 10 | | num > 100){
                message.setText("Number must be\n" +
                                "between 10 and 100");
                inputText.setText(""); 
                }
            else{      
            int element =
                linearSearch(input, Integer.parseInt(searchKey));
                if(element != -1){
                    size -= 1;
                    message.setText("Next Integer");
                    inputText.setText("");
                    count++;
                    
                }
                if(element == -1){
                    input[count] = Integer.parseInt(inputText.getText());
                    output.append(Integer.toString(input[count]) + "\n");
                    message.setText("Next Integer Please");
                    inputText.setText("");
                    count++;
                }
                if(count == input.length){
                    inputText.setEditable(false);
                    message.setText("Thank You\n" + "Your Done");
                }
                }
                    
       
    }
        
    class PrintAction implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            output.append("\n\nYour Array\n");
        
            for(int i = 0; i < input.length; i++){
                output.append(Integer.toString(input[i]));
                output.append("\n");
            }
        }
    }
    class ResetAction implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            inputText.setEditable(true);
            inputText.requestFocus();
            message.setText("Enter an Integer");
            output.setText("");
        }
    }
    public int linearSearch(int input2[], int key)
    {
        for ( int counter = 0; counter < input2.length; counter++)
            if(input2[counter] == key)
                return counter;
            return -1;
    }
}

ANY help is appreciated Ryan
------------------

[This message has been edited by Ryan Perlman (edited November 15, 2001).]

[William Barnes]

You need a more flexable data structure, arrays are rather static. (Sorry I didn't actaully look at your code.)

[David O'Meara]

You'd have to ask the question in the Performance forum as to whether it is a good thing, but previously I have used the System.arraycopy() method. I tend to use the Collections framework rather than arrays (except on the rare occasion) so it's been a while.
Dave.

[Colin Kenworthy]

Once you create an array it's size cannot be changed. You could (once your 20 numbers have been input) go through your array counting the non-zero ints and create a new array of that size, then go through again copying accross the non-zero ints.
OR you could get into Collections (in which case you would need to use the Integer class instead of int) and discover how simple it is to manipulate a set of objects like Integer.