Netbeans Jtable и resultset

Question

Помогите, пожалуйста, поставить результаты в gui jtable! Если я сам сделаю Jtable из кода - все в порядке <, но если я использую Netbeans, у меня получится ошибка.

В коде я сделал 2 таблицы <, но я не могу поместить их источник данных в myTable.

/* 
* To change this license header, choose License Headers in Project Properties. 
* To change this template file, choose Tools | Templates 
* and open the template in the editor. 
*/ 

package db; 

/** 
* 
* @author ma.matveev 
*/ 
import java.sql.CallableStatement; 
import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.*; 
import javax.swing.table.*; 
import java.util.*; 
import java.util.logging.Level; 
import java.util.logging.Logger; 
import javax.swing.*; 

public class Table extends javax.swing.JFrame { 
    //Connection conn = null; 
    //ResultSet rs = null; 
    // PreparedStatement pst = null; 

    /** 
    * Creates new form Table 
    */ 
    public Table() throws ClassNotFoundException { 
     try { 
      // Connect_db.ConnectDb("root","root"); 
      Update_table(); 
      tableOutput() ; 
     } catch (SQLException ex) { 
      Logger.getLogger(Table.class.getName()).log(Level.SEVERE, null, ex); 
     } 

     initComponents(); 
    } 

    public void tableOutput() throws SQLException, ClassNotFoundException { 

Class.forName ("oracle.jdbc.OracleDriver"); 


Connection conn = DriverManager.getConnection 
    ("jdbc:oracle:thin:@//10.123.3.6:1521/rootdb", "root" , "root"); 

//Statement statement = conn.createStatement(); 
    // ResultSet rs=statement.executeQuery("select * from V$Version v "); 
    // ResultSetMetaData rsmetadata = rs.getMetaData(); 
Statement ps = conn.createStatement(); 
ResultSet rs = ps.executeQuery("select * from V$Version v "); 
ResultSetMetaData md = rs.getMetaData(); 
int columnCount = md.getColumnCount(); 
Vector data = new Vector(columnCount); 
Vector row = new Vector(columnCount); 
Vector columnNames = new Vector(columnCount); 

columnNames.add("1"); 
columnNames.add("2"); 
columnNames.add("3"); 
columnNames.add("4"); 
columnNames.add("5"); 
columnNames.add("6"); 
columnNames.add("7"); 
columnNames.add("8"); 
columnNames.add("9"); 
columnNames.add("10"); 

while (rs.next()) { 
for (int i = 1; i <= columnCount; i++) { 
row.addElement(rs.getObject(i)); 
} 
data.addElement(row); 
row = new Vector(columnCount); // Create a new row Vector 
} 
TableModel tm = new DefaultTableModel(data, columnNames) { 
@Override 
public boolean isCellEditable(int rowIndex, int columnIndex) { 
return false; 
} 

}; 
////jTableSchedule.setModel(tm); 
//jTableSchedule.setFont(new Font("Tahoma", Font.PLAIN, 12)); 
    myTable.setModel(tm); 
    } 

private void Update_table() throws SQLException { 
      try { 
      Class.forName ("oracle.jdbc.OracleDriver"); 
       } catch (ClassNotFoundException ex) { 
      Logger.getLogger(Table.class.getName()).log(Level.SEVERE, null, ex); 
                } 
    Connection conn = DriverManager.getConnection 
    ("jdbc:oracle:thin:@//10.123.3.6:1521/rootdb", "root" , "root"); 


    Statement statement = conn.createStatement(); 
    ResultSet rs=statement.executeQuery("select * from V$Version v "); 
    ResultSetMetaData rsmetadata = rs.getMetaData(); 
    int columns = rsmetadata.getColumnCount(); 
    DefaultTableModel dtm = new DefaultTableModel(); 
    Vector columns_name = new Vector(); 
    Vector data_rows = new Vector(); 
    //System.out.println(columns); 
    for (int i=1; i<=columns; i++){ 
    // System.out.println(i); 
    columns_name.addElement(rsmetadata.getColumnName(i)); 

    } 
    // System.out.println(columns_name); 
    dtm.setColumnIdentifiers(columns_name); 



    while (rs.next()) { 
     // System.out.println(rs.getObject(1)); 
     data_rows = new Vector(); 
     for (int j=1; j<=columns; j++){ 
     data_rows.addElement(rs.getString(j)); 

     //System.out.println("123"); 
     //System.out.println(rs.getString(j)); 
     } 
     //System.out.println(rs.getObject(1)); 
     //System.out.println(data_rows.isEmpty()); 
     //System.out.println(rs.getObject(1)); 
     dtm.addRow(data_rows); 

     //data.addElement(data_rows); 
     // System.out.println(data.lastElement()); 

           } 




    JTable table = new JTable(dtm); 
    // JTable myTable = new JTable(dtm); 
    JOptionPane.showMessageDialog(null, new JScrollPane(table)); 
    //JOptionPane.showMessageDialog(null, new JScrollPane(myTable)); 


    //System.out.println(dtm.getColumnName(0)); 
    String[][] data = new String[1][4]; 
    data[0][0]="1"; 
data[0][1]="1"; 
data[0][2]="1"; 
data[0][3]="1"; 

String[] columnNames = new String[]{ 
    "IP", "PC_NAME", "ttl", "db" 
}; 
DefaultTableModel model = new DefaultTableModel(data,columnNames); 

JTable table1 = new JTable(model); 
    // JTable myTable = new JTable(dtm); 
    JOptionPane.showMessageDialog(null, new JScrollPane(table1)); 
    // myTable.setModel(dtm); 


//myTable.setModel(DbUtils.resultSetToTableModel(rs)); 
} 
    /** 
    * 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") 
    // <editor-fold defaultstate="collapsed" desc="Generated Code">       
    private void initComponents() { 

     jScrollPane2 = new javax.swing.JScrollPane(); 
     myTable = new javax.swing.JTable(); 

     setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); 

     myTable.setModel(new javax.swing.table.DefaultTableModel(
      new Object [][] { 
       {null, null, null, null}, 
       {null, null, null, null}, 
       {null, null, null, null}, 
       {null, null, null, null} 
      }, 
      new String [] { 
       "Title 1", "Title 2", "Title 3", "Title 4" 
      } 
     )); 
     jScrollPane2.setViewportView(myTable); 

     javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); 
     getContentPane().setLayout(layout); 
     layout.setHorizontalGroup(
      layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
      .addGroup(layout.createSequentialGroup() 
       .addContainerGap() 
       .addComponent(jScrollPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 375, javax.swing.GroupLayout.PREFERRED_SIZE) 
       .addContainerGap(15, Short.MAX_VALUE)) 
     ); 
     layout.setVerticalGroup(
      layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
      .addGroup(layout.createSequentialGroup() 
       .addContainerGap() 
       .addComponent(jScrollPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 275, javax.swing.GroupLayout.PREFERRED_SIZE) 
       .addContainerGap(14, Short.MAX_VALUE)) 
     ); 

     pack(); 
    }// </editor-fold>       

    /** 
    * @param args the command line arguments 
    */ 
    public static void main(String args[]) { 
     /* Set the Nimbus look and feel */ 
     //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) "> 
     /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel. 
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */ 
     try { 
      for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) { 
       if ("Nimbus".equals(info.getName())) { 
        javax.swing.UIManager.setLookAndFeel(info.getClassName()); 
        break; 
       } 
      } 
     } catch (ClassNotFoundException ex) { 
      java.util.logging.Logger.getLogger(Table.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } catch (InstantiationException ex) { 
      java.util.logging.Logger.getLogger(Table.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } catch (IllegalAccessException ex) { 
      java.util.logging.Logger.getLogger(Table.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } catch (javax.swing.UnsupportedLookAndFeelException ex) { 
      java.util.logging.Logger.getLogger(Table.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } 
     //</editor-fold> 

     /* Create and display the form */ 
     java.awt.EventQueue.invokeLater(new Runnable() { 
      public void run() { 
       try { 
        new Table().setVisible(true); 
       } catch (ClassNotFoundException ex) { 
        Logger.getLogger(Table.class.getName()).log(Level.SEVERE, null, ex); 
       } 
      } 
     }); 
    } 

    // Variables declaration - do not modify      
    private javax.swing.JScrollPane jScrollPane2; 
    public javax.swing.JTable myTable; 
    // End of variables declaration     
} 

Ошибка, если я хочу поставить в ГИП MYTABLE

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException 
    at db.Table.tableOutput(Table.java:89) 
    at db.Table.<init>(Table.java:35) 
    at db.Table$2.run(Table.java:246) 
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251) 
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:733) 
    at java.awt.EventQueue.access$200(EventQueue.java:103) 
    at java.awt.EventQueue$3.run(EventQueue.java:694) 
    at java.awt.EventQueue$3.run(EventQueue.java:692) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) 
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:703) 
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) 
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) 
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) 
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) 
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) 
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:91) 
ПОСТРОЕНИЕ УСПЕШНО ЗАВЕРШЕНО (общее время: 10 секунд) 

Answer 1

Прочитайте ошибку. Это говорит вам, что вы пытаетесь использовать объект в строке 89 Table.java, который является нулевым. Это, как представляется, эта строка:

myTable.setModel(tm); 

, что означает, что myTable никогда не instatiated. Вы не можете назвать setModel(...), пока первый не называйте myTable = new JTable(...);

EDIT: В конструкторе, вы звоните tableOutput() до вашего звонка в initComponents(). Сначала вызовите initComponents() в свой конструктор перед блоком try-catch.