GUI TextArea

Question

I have a GUI class (as follows) my problem is that i can't change the text in it appart from at the constructor stage. The bold text in the constructor works fine, but the bold line at the bottom doesn't put the text i want in the textarea, i get a null pointer exception! Can anyone tell me my i can't get acccess to the Results TextArea, or how i can access it. Ignore the rest of the code it all works fine.
// GUI1 CLASS
import java.awt.event.*;
import java.awt.*;
import java.io.*;
import java.util.*;
//construcs a class inside a frame and implements ActionListener(Mouse Clicks,
//button presses etc.) and WindowListener(Close window, minimise, etc.)
class GUI1 extends Frame implements ActionListener, WindowListener{
     //-------------FIELDS-----------------
     TextField QTermTF;
     private String allUrls;
     //private String SingleUrl;
     private String SingleHTML;
     private String SingleHTMLnoTags;
     private String SingleHTMLnoTagsnoPunc;
//private Vector WordList;
     private String WordToListTest;
     //private java.util.List WordList = new LinkedList();
private Vector WordList = new Vector();
     private Vector noiseWordList = new Vector();
     private Vector WordsNoNoise = new Vector();
     private Vector WordListFormated = new Vector();
     private Vector SingleUrl = new Vector();
     private Vector TopFiveWords;
     private Vector AllWords = new Vector();
     //Vector TopFiveWords = new Vector();
     //Vector AllWords = new Vector();
     public TextArea Results;
     private String OutputTermsS = "";
     //------------CONSTRUCTOR---------------
     GUI1(String s){
     //inherits String s from super class main
     super(s);
     //setbackgroung colour
     setBackground(Color.yellow);
     setLayout(new FlowLayout());
     //adds Window Listener to enable close window etc
     addWindowListener(this);
     //Adds Text Area
     TextArea Results = new TextArea(5,45);
     Results.setLocation(3000,40);     
     add(Results);
     Results.setText("hello");
     //defines a new button called pushbutton with label "Search Now
     Button pushButton = new Button("Search Now");
     //set button location
     pushButton.setLocation(10,40);
//adds Button called pushButton to Frame
     add(pushButton);
//adds ActionListener for pushbutton
pushButton.addActionListener(this);
     //adds TextFields
     QTermTF = new TextField(30);
     QTermTF.setLocation(50,40);
     add(QTermTF);
     QTermTF.addActionListener(this);
     //------------METHODS------------------
     //Methods to close window, maximise etc.
     public void windowClosed(WindowEvent event){}
     public void windowDeiconified(WindowEvent event){}
     public void windowIconified(WindowEvent event){}
     public void windowActivated(WindowEvent event){}
     public void windowDeactivated(WindowEvent event){}
     public void windowOpened(WindowEvent event){}
     public void windowClosing(WindowEvent event){
          System.exit(0);
//method used to perform actions when "event occurs"
public void actionPerformed(ActionEvent event){
          String QTerm = "";     
          if (event.getActionCommand().equals("Search Now")){
               QTerm = QTermTF.getText();
               QTerm = QTerm.replace(' ', '+');
               //System.out.println(QTerm);
     //Call SEInit constructor with String QTerm as Argument
     SEInit1 newSEInit1 = new SEInit1(QTerm);
     allUrls=(newSEInit1.collectUrls());
     //System.out.println(allUrls);
     DocStore newDocStore = new DocStore(allUrls);
     SingleUrl =(newDocStore.GetSingleUrl());
     //System.out.println(SingleUrl);
     int f = 0;
     while( f < SingleUrl.size()){
     Object SingleurlO = SingleUrl.get(f);     
     String SingleUrlS = (String) SingleurlO;
     //System.out.println(SingleUrlS);
     SingleHTML = (newDocStore.GetHTML(SingleUrlS));
     //System.out.println(SingleHTML);     
     SingleHTMLnoTags = (newDocStore.RemoveTags(SingleHTML));
     //System.out.println(SingleHTMLnoTags);
     SingleHTMLnoTagsnoPunc = (newDocStore.RemovePunc(SingleHTMLnoTags));
     //System.out.println(SingleHTMLnoTagsnoPunc);
WordList = (newDocStore.WordsToList(SingleHTMLnoTagsnoPunc));
     //System.out.println(WordList.get(21));
     //System.out.println(WordList.size());     
     WordListFormated = (newDocStore.FormatWordList(WordList));
     //System.out.println(WordListFormated.size());
     //System.out.println(WordListFormated);
     noiseWordList = (newDocStore.GetNoiseWords());
     //System.out.println(noiseWordList.get(23));
     //System.out.println(noiseWordList.size());
     WordsNoNoise = (newDocStore.RemoveNoiseWords(WordListFormated,noiseWordList));
     //System.out.println(WordsNoNoise.size());     
     //System.out.println(WordsNoNoise.get(21));
     //System.out.println(WordsNoNoise);     
     Sort newSort = new Sort(WordsNoNoise);
     TopFiveWords = (newSort.GetTopFive());
     //System.out.println("TopFiveWords="+TopFiveWords);
     int t=0;
     while(t < TopFiveWords.size()){
          Object OneWord = TopFiveWords.get(t);
          AllWords.add(OneWord);
     t++;
     //System.out.println("you say");
     f++;
     //System.out.println(AllWords);
     Object Test93 = AllWords.get(19);
     String Test93S = (String) Test93;
     //System.out.println(Test93S);
     Sort newSort = new Sort(WordsNoNoise);
     Vector OutputTerms = newSort.RemoveNulls(AllWords);
     //System.out.println(OutputTerms);
     int w = 0;
     while(w < OutputTerms.size()){
     System.out.println("hello");
     OutputTermsS = (OutputTermsS+" "+OutputTerms.get(w));
     w++;
     System.out.println(OutputTermsS);     
     Results.setText(OutputTermsS);
     //Call GUI constructor
     public static void main(String[] args){
          GUI1 screen = new GUI1("SEARCH TOOL");
          screen.setSize(500,300);
          screen.setVisible(true);

Answer 1

Well, I can't see what's wrong. It's hard to debug without all the code, line numbers etc, but I might be able to help you debug it.
My favorite way of tracking down NullPointerExceptions is to put the line
System.out.println("OutputTermsS == null .... " + (OutputTermsS==null));
just before anything goes wrong. See if it is null (I don't think it is). Put similar print statements for any other variables, anything that could be null.
What you've described doesn't seem kosher... if the NullPointerException is thrown on that line, it means something was wrong and it didn't get to print out. There's gremlins in here somewhere....
I still think that it's somewhere in the actionPerformed method is the null, and (somehow) the line numbering is skew-if. Perhaps you only copied a section (one class) of code from the file, but the numbering includes the whole file?
Cheers,
Radish21