title: Display list on a jframe
body: <p>i want to show the list on the jframe form. any help is appreciated </p>
  
  <pre><code>import java.util.List;
  import java.util.ArrayList;
  
  
  public class Collatz extends javax.swing.JFrame {
  
      /** Creates new form Collatz */
      public Collatz() {
          initComponents();
      }
  
      /** This method is called from within the constructor to
       * initialize the form.
       * WARNING: Do NOT modify this code. The content of this method is
       * always regenerated by the Form Editor.
       */
      @SuppressWarnings("unchecked")
      // &lt;editor-fold defaultstate="collapsed" desc="Generated Code"&gt;                          
      private void initComponents() {
  
          jLabel1 = new javax.swing.JLabel();
          jTextField1 = new javax.swing.JTextField();
          jButton1 = new javax.swing.JButton();
          jScrollPane1 = new javax.swing.JScrollPane();
          jList1 = new javax.swing.JList();
          jScrollPane3 = new javax.swing.JScrollPane();
          jScrollPane2 = new javax.swing.JScrollPane();
  
          setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
  
          jLabel1.setText("Loop (If Applicable)");
  
          jTextField1.setText("Intial Number");
          jTextField1.addActionListener(new java.awt.event.ActionListener() {
              public void actionPerformed(java.awt.event.ActionEvent evt) {
                  jTextField1ActionPerformed(evt);
              }
          });
  
          jButton1.setText("Go!");
          jButton1.addActionListener(new java.awt.event.ActionListener() {
              public void actionPerformed(java.awt.event.ActionEvent evt) {
                  jButton1ActionPerformed(evt);
              }
          });
  
          jList1.setModel(new javax.swing.AbstractListModel() {
              String[] strings = { "Item 1", "Item 2", "Item 3", "Item 4", "Item 5" };
              public int getSize() { return strings.length; }
              public Object getElementAt(int i) { return strings[i]; }
          });
          jScrollPane1.setViewportView(jList1);
  
          jScrollPane3.setViewportView(jScrollPane2);
  
          org.jdesktop.layout.GroupLayout layout = new org.jdesktop.layout.GroupLayout(getContentPane());
          getContentPane().setLayout(layout);
          layout.setHorizontalGroup(
              layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
              .add(org.jdesktop.layout.GroupLayout.TRAILING, layout.createSequentialGroup()
                  .add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
                      .add(layout.createSequentialGroup()
                          .add(60, 60, 60)
                          .add(jTextField1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 128, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
                      .add(layout.createSequentialGroup()
                          .add(108, 108, 108)
                          .add(jLabel1)))
                  .addPreferredGap(org.jdesktop.layout.LayoutStyle.RELATED, 40, Short.MAX_VALUE)
                  .add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
                      .add(layout.createSequentialGroup()
                          .add(jScrollPane1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE)
                          .addPreferredGap(org.jdesktop.layout.LayoutStyle.RELATED)
                          .add(jScrollPane3, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 14, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE)
                          .addContainerGap())
                      .add(org.jdesktop.layout.GroupLayout.TRAILING, layout.createSequentialGroup()
                          .add(jButton1)
                          .add(70, 70, 70))))
          );
          layout.setVerticalGroup(
              layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
              .add(layout.createSequentialGroup()
                  .add(60, 60, 60)
                  .add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.TRAILING)
                      .add(jButton1)
                      .add(jTextField1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
                  .add(layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
                      .add(layout.createSequentialGroup()
                          .add(76, 76, 76)
                          .add(jLabel1))
                      .add(layout.createSequentialGroup()
                          .addPreferredGap(org.jdesktop.layout.LayoutStyle.RELATED)
                          .add(jScrollPane1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
                      .add(layout.createSequentialGroup()
                          .add(18, 18, 18)
                          .add(jScrollPane3, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 64, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE)))
                  .addContainerGap(62, Short.MAX_VALUE))
          );
  
          pack();
      }// &lt;/editor-fold&gt;                        
  
      private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
       double c;
                 c =  Double.parseDouble(jTextField1.getText());
  
                  List&lt;String&gt; ls=new ArrayList&lt;String&gt;();
  
                  ls.add(String.valueOf(c));
  
  
  
  
                 do {
         if (c == -5) {jLabel1.setText("loop = −5 → −14 → −7 → −20 → −10 → −5");}
       if (c == -17) {jLabel1.setText("loop = −17 → −50 → −25 → −74 → −37 → −110 "
                  + "→ −55 → −164 → −82 → −41 → −122 → −61 → "
                  + "−182 → −91 → −272 → −136 → −68 → −34 → −17 … ");}
           if (c == -1) {jLabel1.setText("loop = -1 → -2 → -1 ");}
            if (c == 0) {jLabel1.setText("loop = 0 → 0");}
            if (c == 1) {jLabel1.setText("loop = 1 → 4 → 2 → 1");}
            if (c != -5) {jLabel1.setText("Loop (If Applicable)");}
                 /**if (c != -17) {jLabel1.setText("Loop (If Applicable)");}
                 if (c != -1) {jLabel1.setText("Loop (If Applicable)");}
                 if (c != 0) {jLabel1.setText("Loop (If Applicable)");}
                 if (c != 1) {jLabel1.setText("Loop (If Applicable)");}
                 **/ if (c != 1){
  
          double n;
          n = Double.parseDouble(jTextField1.getText());
  
          if (( n % 2 ) == 0) {
  
                    try{
  Thread.sleep(50); // Sleep for 4 sec
  }
  catch(InterruptedException e){} 
  
          double x, r; 
          x = Double.parseDouble(jTextField1.getText());
  
          r = x/2; 
          ls.add(String.valueOf(r));
          jTextField1.setText(String.valueOf(r));
  
  
  
  
  
          } 
  
  
          if (( n % 2) != 0){  
                                try{
  Thread.sleep(50); // Sleep for 4 sec
  }
  catch(InterruptedException e){} 
  
              double x, r; 
          x = Double.parseDouble(jTextField1.getText());
          r = (0x3*x)+1; 
          ls.add(String.valueOf(r));
          jTextField1.setText(String.valueOf(r));
  
          } 
  
  
        } 
      }                                        
  
                  while (c != 1);  }    
      private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) {                                            
          // TODO add your handling code here:
      }                                           
  
      /**
      * @param args the command line arguments
      */
      public static void main(String args[]) {
          java.awt.EventQueue.invokeLater(new Runnable() {
              public void run() {
                  new Collatz().setVisible(true);
              }
          });
      }
  </code></pre>