How do initialize these Strings?

[eLancaster]

I solved the problem that i originally wrote this thread for, but i have another problem, Why do lines 81-86 throw a null pointer exception?!

Code:
StartsWithLetter.java

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTextField;


public class StartsWithLetter extends JFrame{
	private JTextField inputWordField;//
	private JButton addButton;//
	private JButton sortButton;
	private JList inputWordList;//
	private JList sortedWordList;//
	private static String[] inputWords;
	private static int inputWordsCount = 0;
	private static String[] sortedWords;
	private static int sortedWordsCount=0;

	
	public StartsWithLetter()
	{
		super("Find words that start with");
		setLayout(new FlowLayout());
		
		inputWords = new String[5];
		sortedWords = new String[5];
		
		//word entered here
		inputWordField = new JTextField("Enter Word Here");
		add(inputWordField);
		
		//word is added to array and list is refreshed
		addButton = new JButton("Add to List");
		add(addButton);
		
		sortButton = new JButton("Sort");
		add(sortButton);
		
		inputWordList = new JList(inputWords);
		inputWordList.setVisibleRowCount(5);
		inputWordList.setFixedCellHeight(20);
		inputWordList.setFixedCellWidth(100);
		add(new JScrollPane(inputWordList));
		
		sortedWordList = new JList(sortedWords);
		sortedWordList.setVisibleRowCount(5);
		sortedWordList.setFixedCellHeight(20);
		sortedWordList.setFixedCellWidth(100);
		add(new JScrollPane(sortedWordList));
		
		addButton.addActionListener(
				new ActionListener()
				{
					public void actionPerformed(ActionEvent arg0) {
						String enteredWord;
						enteredWord = inputWordField.getText();
						
						inputWords[inputWordsCount]=enteredWord;
						inputWordsCount++;
						inputWordList.setListData(inputWords);
						
						
					}
					
				}
		);
		
		sortButton.addActionListener(
				new ActionListener()
				{
					public void actionPerformed(ActionEvent arg0) {
					//try{
						for(int index=0;index<inputWords.length;index++)
						{
							{

								if(inputWords[index].startsWith("s"))
								{
									sortedWords[sortedWordsCount]=inputWords[index];
									sortedWordsCount++;
									sortedWordList.setListData(sortedWords);
								}

							
						}
					}
					//catch(Exception e)
					//{
					//		JOptionPane.showMessageDialog(null, "Shit Just Happened","WTF?!",JOptionPane.ERROR_MESSAGE);
					//}
					//	
					//}
					
				}
		);
		
	}
}

Exception Error Message:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at StartsWithLetter$2.actionPerformed(StartsWithLette r.java:81)
at javax.swing.AbstractButton.fireActionPerformed(Abs tractButton.java:2012)
at javax.swing.AbstractButton$Handler.actionPerformed (AbstractButton.java:2335)
at javax.swing.DefaultButtonModel.fireActionPerformed (DefaultButtonModel.java:404)
at javax.swing.DefaultButtonModel.setPressed(DefaultB uttonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseRe leased(BasicButtonListener.java:253)
at java.awt.Component.processMouseEvent(Component.jav a:6175)
at javax.swing.JComponent.processMouseEvent(JComponen t.java:3267)
at java.awt.Component.processEvent(Component.java:594 0)
at java.awt.Container.processEvent(Container.java:210 5)
at java.awt.Component.dispatchEventImpl(Component.jav a:4536)
at java.awt.Container.dispatchEventImpl(Container.jav a:2163)
at java.awt.Component.dispatchEvent(Component.java:43 62)
at java.awt.LightweightDispatcher.retargetMouseEvent( Container.java:4461)
at java.awt.LightweightDispatcher.processMouseEvent(C ontainer.java:4125)
at java.awt.LightweightDispatcher.dispatchEvent(Conta iner.java:4055)
at java.awt.Container.dispatchEventImpl(Container.jav a:2149)
at java.awt.Window.dispatchEventImpl(Window.java:2478 )
at java.awt.Component.dispatchEvent(Component.java:43 62)
at java.awt.EventQueue.dispatchEvent(EventQueue.java: 604)
at java.awt.EventDispatchThread.pumpOneEventForFilter s(EventDispatchThread.java:275)
at java.awt.EventDispatchThread.pumpEventsForFilter(E ventDispatchThread.java:200)
at java.awt.EventDispatchThread.pumpEventsForHierarch y(EventDispatchThread.java:190)
at java.awt.EventDispatchThread.pumpEvents(EventDispa tchThread.java:185)
at java.awt.EventDispatchThread.pumpEvents(EventDispa tchThread.java:177)
at java.awt.EventDispatchThread.run(EventDispatchThre ad.java:138)

[Shoss]

Array's have to be initialized before you can use them.

inputWords = new String[numberofelements];

You can't assign anything to them unless they've been initialized.