code: private JPanel getMainPanel()
      {
          if (mainPanel == null)
          {
              GridBagConstraints gridBagConstraints = new GridBagConstraints();
              gridBagConstraints.insets = new Insets(10, 10, 5, 10);
              gridBagConstraints.gridx = 0;
              gridBagConstraints.fill = java.awt.GridBagConstraints.HORIZONTAL;
              gridBagConstraints.weightx = 1.0;
              gridBagConstraints.gridwidth = 1;
              gridBagConstraints.gridy = 0;
              mainPanel = new JPanel();
              GridBagLayout gbl_mainPanel = new GridBagLayout();
              gbl_mainPanel.rowWeights = new double[]{0.0, 0.0, 0.0};
              gbl_mainPanel.columnWeights = new double[]{1.0};
              mainPanel.setLayout(gbl_mainPanel);
              mainPanel.add(getUrlPanel(), gridBagConstraints);
              GridBagConstraints gbc_tabs = new GridBagConstraints();
              gbc_tabs.weighty = 1.0;
              gbc_tabs.weightx = 1.0;
              gbc_tabs.fill = GridBagConstraints.BOTH;
              gbc_tabs.gridx = 0;
              gbc_tabs.gridy = 1;
              mainPanel.add(getTabs(), gbc_tabs);
              GridBagConstraints gridBagConstraints3 = new GridBagConstraints();
              gridBagConstraints3.gridx = 0;
              gridBagConstraints3.weightx = 1.0;
              gridBagConstraints3.fill = java.awt.GridBagConstraints.HORIZONTAL;
              gridBagConstraints3.gridwidth = 1;
              gridBagConstraints3.gridy = 2;
              mainPanel.add(getStatusPanel(), gridBagConstraints3);
          }
          return mainPanel;
      }
docs: This method initializes jContentPane
  
  @return javax.swing.JPanel