title: JPanel doesn't show up
body: <p><strong>JPanel doesn't show up, i put .setVisible but.. it doesn't show up neither, It builds but it doesn't show up I'm only just a beginner in this part of programming.</strong></p>
  
  <pre><code>    package calculatorv3;
  
  
      public class CalculatorForm extends javax.swing.JPanel {
          private static final long serialVersionUID = 1L;
  
  
         public CalculatorForm() {
              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")
  
          private void initComponents() {
  
              jTextField2 = new javax.swing.JTextField();
              jTextField3 = new javax.swing.JTextField();
              jTextField4 = new javax.swing.JTextField();
              jButton2 = new javax.swing.JButton();
              jButton3 = new javax.swing.JButton();
              jButton4 = new javax.swing.JButton();
              jButton5 = new javax.swing.JButton();
              jButton6 = new javax.swing.JButton();
              jButton7 = new javax.swing.JButton();
              jButton8 = new javax.swing.JButton();
              jButton9 = new javax.swing.JButton();
              jButton10 = new javax.swing.JButton();
              jButton11 = new javax.swing.JButton();
              jButton12 = new javax.swing.JButton();
              jButton13 = new javax.swing.JButton();
              jButton14 = new javax.swing.JButton();
              jButton15 = new javax.swing.JButton();
              jButton1 = new javax.swing.JButton();
              jButton16 = new javax.swing.JButton();
              jButton17 = new javax.swing.JButton();
  
              jButton2.setText("2");
              jButton2.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton2ActionPerformed(evt);
                  }
              });
  
              jButton3.setText("1");
              jButton3.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton3ActionPerformed(evt);
                  }
              });
  
              jButton4.setText("3");
              jButton4.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton4ActionPerformed(evt);
                  }
              });
  
              jButton5.setText("4");
              jButton5.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton5ActionPerformed(evt);
                  }
              });
  
              jButton6.setText("5");
              jButton6.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton6ActionPerformed(evt);
                  }
              });
  
              jButton7.setText("6");
              jButton7.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton7ActionPerformed(evt);
                  }
              });
  
              jButton8.setText("7");
              jButton8.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton8ActionPerformed(evt);
                  }
              });
  
              jButton9.setText("8");
              jButton9.addActionListener(new java.awt.event.ActionListener() {
                  public void actionPerformed(java.awt.event.ActionEvent evt) {
                      jButton9ActionPerformed(evt);
                  }
              });
  
              jButton10.setText("9");
  
              jButton11.setText("0");
  
              jButton12.setText("Add");
  
              jButton13.setText("Sub");
  
              jButton14.setText("Mul");
  
              jButton15.setText("Div");
  
              jButton1.setText("Enter");
  
              jButton16.setText("Reset");
  
              jButton17.setText("Equals");
  
              javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
              this.setLayout(layout);
              layout.setHorizontalGroup(
                  layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                  .addGroup(layout.createSequentialGroup()
                      .addContainerGap()
                      .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                          .addComponent(jTextField2)
                          .addComponent(jTextField3)
                          .addComponent(jTextField4)
                          .addGroup(layout.createSequentialGroup()
                              .addComponent(jButton3)
                              .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                              .addComponent(jButton2)
                              .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                              .addComponent(jButton4)
                              .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                              .addComponent(jButton5)
                              .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                              .addComponent(jButton6)
                              .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                              .addComponent(jButton12)
                              .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                              .addComponent(jButton14))
                          .addGroup(layout.createSequentialGroup()
                              .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                                  .addGroup(layout.createSequentialGroup()
                                      .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                      .addComponent(jButton16, javax.swing.GroupLayout.PREFERRED_SIZE, 113, javax.swing.GroupLayout.PREFERRED_SIZE))
                                  .addGroup(layout.createSequentialGroup()
                                      .addComponent(jButton7)
                                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                      .addComponent(jButton8)
                                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                      .addComponent(jButton9)
                                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                                      .addComponent(jButton10)
                                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                                      .addComponent(jButton11)))
                              .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                              .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                                  .addGroup(layout.createSequentialGroup()
                                      .addComponent(jButton13)
                                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                      .addComponent(jButton15)
                                      .addGap(0, 0, Short.MAX_VALUE))
                                  .addComponent(jButton17, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))))
                      .addContainerGap())
              );
              layout.setVerticalGroup(
                  layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                  .addGroup(layout.createSequentialGroup()
                      .addContainerGap()
                      .addComponent(jTextField2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                      .addComponent(jTextField3, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                      .addComponent(jTextField4, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                      .addGap(7, 7, 7)
                      .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                          .addComponent(jButton3)
                          .addComponent(jButton2)
                          .addComponent(jButton4)
                          .addComponent(jButton5)
                          .addComponent(jButton6)
                          .addComponent(jButton12)
                          .addComponent(jButton14))
                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                      .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                          .addComponent(jButton7)
                          .addComponent(jButton8)
                          .addComponent(jButton9)
                          .addComponent(jButton10)
                          .addComponent(jButton11)
                          .addComponent(jButton13)
                          .addComponent(jButton15))
                      .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                      .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                          .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                          .addComponent(jButton17, javax.swing.GroupLayout.DEFAULT_SIZE, 40, Short.MAX_VALUE)
                          .addComponent(jButton16))
                      .addContainerGap())
              );
          }// &lt;/editor-fold&gt;
  
          private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          private void jButton4ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          private void jButton5ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          private void jButton6ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          private void jButton7ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          private void jButton8ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          private void jButton9ActionPerformed(java.awt.event.ActionEvent evt) {
              // TODO add your handling code here:
          }
  
          // Variables declaration - do not modify
          private javax.swing.JButton jButton1;
          private javax.swing.JButton jButton10;
          private javax.swing.JButton jButton11;
          private javax.swing.JButton jButton12;
          private javax.swing.JButton jButton13;
          private javax.swing.JButton jButton14;
          private javax.swing.JButton jButton15;
          private javax.swing.JButton jButton16;
          private javax.swing.JButton jButton17;
          private javax.swing.JButton jButton2;
          private javax.swing.JButton jButton3;
          private javax.swing.JButton jButton4;
          private javax.swing.JButton jButton5;
          private javax.swing.JButton jButton6;
          private javax.swing.JButton jButton7;
          private javax.swing.JButton jButton8;
          private javax.swing.JButton jButton9;
          private javax.swing.JTextField jTextField2;
          private javax.swing.JTextField jTextField3;
          private javax.swing.JTextField jTextField4;
          // End of variables declaration
  
          public static void main(String args[]) {
              java.awt.EventQueue.invokeLater(new Runnable() {
                  @Override
                  public void run() {
                      new CalculatorForm().setVisible(true);
                  }
              });
          }
  
          }
  </code></pre>
  
  <p><strong>I can't find out what's wrong in my code, don't bother the typo errors "the numbering of the buttons" I'am only concern on how to show the Panel up</strong> </p>
  
  <p>Ok I edited the code I merge it with the public static void main.. for one time init</p>
  
  <p>import javax.swing.JButton;
  import javax.swing.JTextField;</p>
  
  <pre><code>/*
   * To change this template, choose Tools | Templates
   * and open the template in the editor.
   */
  
  /**
   *
   * @author Jfetizanan
   */
  public class NewMain {
  
      /**
       * @param args the command line arguments
       */
      public static void main(String[] args) {
  
          JTextField jTextField2 = new javax.swing.JTextField();
          JTextField jTextField3 = new javax.swing.JTextField();
          JTextField jTextField4 = new javax.swing.JTextField();
          JButton jButton2 = new javax.swing.JButton();
          JButton jButton3 = new javax.swing.JButton();
          JButton jButton4 = new javax.swing.JButton();
          JButton jButton5 = new javax.swing.JButton();
          JButton jButton6 = new javax.swing.JButton();
          JButton jButton7 = new javax.swing.JButton();
          JButton jButton8 = new javax.swing.JButton();
          JButton jButton9 = new javax.swing.JButton();
          JButton jButton10 = new javax.swing.JButton();
          JButton jButton11 = new javax.swing.JButton();
          JButton jButton12 = new javax.swing.JButton();
          JButton jButton13 = new javax.swing.JButton();
          JButton jButton14 = new javax.swing.JButton();
          JButton jButton15 = new javax.swing.JButton();
          JButton jButton1 = new javax.swing.JButton();
          JButton jButton16 = new javax.swing.JButton();
          JButton jButton17 = new javax.swing.JButton();
  
          jButton2.setText("2");
          jButton2.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton3.setText("1");
          jButton3.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton4.setText("3");
          jButton4.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton5.setText("4");
          jButton5.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton6.setText("5");
          jButton6.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton7.setText("6");
          jButton7.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton8.setText("7");
          jButton8.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton9.setText("8");
          jButton9.addActionListener(new java.awt.event.ActionListener() {
              @Override
              public void actionPerformed(java.awt.event.ActionEvent evt) {
  
              }
          });
  
          jButton10.setText("9");
  
          jButton11.setText("0");
  
          jButton12.setText("Add");
  
          jButton13.setText("Sub");
  
          jButton14.setText("Mul");
  
          jButton15.setText("Div");
  
          jButton1.setText("Enter");
  
          jButton16.setText("Reset");
  
          jButton17.setText("Equals");
  
          javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
          this.setLayout(layout);
          layout.setHorizontalGroup(
              layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
              .addGroup(layout.createSequentialGroup()
                  .addContainerGap()
                  .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                      .addComponent(jTextField2)
                      .addComponent(jTextField3)
                      .addComponent(jTextField4)
                      .addGroup(layout.createSequentialGroup()
                          .addComponent(jButton3)
                          .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                          .addComponent(jButton2)
                          .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                          .addComponent(jButton4)
                          .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                          .addComponent(jButton5)
                          .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                          .addComponent(jButton6)
                          .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                          .addComponent(jButton12)
                          .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                          .addComponent(jButton14))
                      .addGroup(layout.createSequentialGroup()
                          .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                              .addGroup(layout.createSequentialGroup()
                                  .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                  .addComponent(jButton16, javax.swing.GroupLayout.PREFERRED_SIZE, 113, javax.swing.GroupLayout.PREFERRED_SIZE))
                              .addGroup(layout.createSequentialGroup()
                                  .addComponent(jButton7)
                                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                  .addComponent(jButton8)
                                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                  .addComponent(jButton9)
                                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                                  .addComponent(jButton10)
                                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                                  .addComponent(jButton11)))
                          .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                          .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                              .addGroup(layout.createSequentialGroup()
                                  .addComponent(jButton13)
                                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
                                  .addComponent(jButton15)
                                  .addGap(0, 0, Short.MAX_VALUE))
                              .addComponent(jButton17, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))))
                  .addContainerGap())
          );
          layout.setVerticalGroup(
              layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
              .addGroup(layout.createSequentialGroup()
                  .addContainerGap()
                  .addComponent(jTextField2, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                  .addComponent(jTextField3, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                  .addComponent(jTextField4, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                  .addGap(7, 7, 7)
                  .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                      .addComponent(jButton3)
                      .addComponent(jButton2)
                      .addComponent(jButton4)
                      .addComponent(jButton5)
                      .addComponent(jButton6)
                      .addComponent(jButton12)
                      .addComponent(jButton14))
                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                  .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                      .addComponent(jButton7)
                      .addComponent(jButton8)
                      .addComponent(jButton9)
                      .addComponent(jButton10)
                      .addComponent(jButton11)
                      .addComponent(jButton13)
                      .addComponent(jButton15))
                  .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                  .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                      .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                      .addComponent(jButton17, javax.swing.GroupLayout.DEFAULT_SIZE, 40, Short.MAX_VALUE)
                      .addComponent(jButton16))
                  .addContainerGap())
          );
  
      }
  }
  </code></pre>
  
  <p><strong>But how about this, it shows errors</strong></p>
  
  <pre><code>javax.swing.GroupLayout layout = new javax.swing.GroupLayout(this);
          this.setLayout(layout);
  </code></pre>
  
  <p><strong>How can I add all objects to the Frame</strong></p>
  
  <p><strong>Ok I finally finish the code.. here it is Thanks</strong></p>
  
  <p><img src="https://i.stack.imgur.com/CVhoL.jpg" alt="The program itself..."></p>