如何從jtable插入數據到mysql數據庫

Question

我想插入jtable多行數據到保存按鈕點擊mysql數據庫。它給一些錯誤....

這是我的代碼...

package my.bill; 


import java.awt.*; 
import java.awt.event.*; 
import java.awt.event.*; 
import java.io.*; 
import java.lang.*; 
import java.sql.*; 
import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.PreparedStatement; 
import java.sql.SQLException; 
import java.util.*; 
import java.util.Calendar; 
import java.util.GregorianCalendar; 
import javax.swing.*; 
import javax.swing.event.*; 
import javax.swing.table.*; 
import javax .swing.table.DefaultTableModel; 


public class bill extends javax.swing.JFrame { 

    /** 
    * Creates new form bill 
    */ 
    Object[][] data=null; 
    String[] columnNames = new String[2]; 

    /*static final String JDBC_DRIVER = "com.mysql.jdbc.Driver"; 
    static final String DB_URL="jdbc:mysql://localhost:3306/gdb?zeroDateTimeBehavior=convertToNull"; 
    //static final String DB_URL = "jdbc:mysql://localhost/"; 

    // Database credentials 
    static final String USER = "root"; 
    static final String PASS = "root";*/ 



    public bill() { 
     initComponents(); 
     CurrentDate(); 

      } 

    public void CurrentDate(){ 
    Calendar cal=new GregorianCalendar(); 
    int month=cal.get(Calendar.MONTH); 
    int year=cal.get(Calendar.YEAR); 
    int day=cal.get(Calendar.DAY_OF_MONTH); 
    Date.setText(day+"-"+(month+1)+"-"+year); 
    } 



    @SuppressWarnings("unchecked") 
    // <editor-fold defaultstate="collapsed" desc="Generated Code">       
    private void initComponents() { 

     jLabel1 = new javax.swing.JLabel(); 
     Date = new javax.swing.JTextField(); 
     jScrollPane2 = new javax.swing.JScrollPane(); 
     jTable1 = new javax.swing.JTable(); 
     netprofit = new javax.swing.JButton(); 
     netsum = new javax.swing.JTextField(); 
     save = new javax.swing.JButton(); 
     jMenuBar1 = new javax.swing.JMenuBar(); 
     jMenu1 = new javax.swing.JMenu(); 
     jMenu2 = new javax.swing.JMenu(); 

     setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); 

     jLabel1.setText("Date"); 

     Date.addActionListener(new java.awt.event.ActionListener() { 
      public void actionPerformed(java.awt.event.ActionEvent evt) { 
       DateActionPerformed(evt); 
      } 
     }); 

     jTable1.setBorder(javax.swing.BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0))); 
     jTable1.setFont(new java.awt.Font("Tahoma", 0, 18)); // NOI18N 
     jTable1.setModel(new javax.swing.table.DefaultTableModel(
      new Object [][] { 
       {"", null, null, null, null, null}, 
       {"", null, null, null, "", null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null}, 
       {null, null, null, null, null, null} 
      }, 
      new String [] { 
       "Job No", "Item", "Billed Amount", "Parts cost", "Net Profit", "Percentage" 
      } 
     )); 
     jTable1.setColumnSelectionAllowed(true); 
     jTable1.setGridColor(new java.awt.Color(0, 0, 0)); 
     jTable1.setRowHeight(20); 
     jTable1.setRowMargin(2); 
     jTable1.setSelectionBackground(new java.awt.Color(255, 255, 255)); 
     jTable1.addInputMethodListener(new java.awt.event.InputMethodListener() { 
      public void caretPositionChanged(java.awt.event.InputMethodEvent evt) { 
      } 
      public void inputMethodTextChanged(java.awt.event.InputMethodEvent evt) { 
       jTable1InputMethodTextChanged(evt); 
      } 
     }); 
     jScrollPane2.setViewportView(jTable1); 
     jTable1.getColumnModel().getSelectionModel().setSelectionMode(javax.swing.ListSelectionModel.SINGLE_SELECTION); 
     if (jTable1.getColumnModel().getColumnCount() > 0) { 
      jTable1.getColumnModel().getColumn(0).setHeaderValue("Job No"); 
      jTable1.getColumnModel().getColumn(1).setHeaderValue("Item"); 
      jTable1.getColumnModel().getColumn(2).setHeaderValue("Billed Amount"); 
      jTable1.getColumnModel().getColumn(3).setHeaderValue("Parts cost"); 
      jTable1.getColumnModel().getColumn(4).setHeaderValue("Net Profit"); 
      jTable1.getColumnModel().getColumn(5).setHeaderValue("Percentage"); 
     } 

     netprofit.setText("Total Profit"); 
     netprofit.addActionListener(new java.awt.event.ActionListener() { 
      public void actionPerformed(java.awt.event.ActionEvent evt) { 
       netprofitActionPerformed(evt); 
      } 
     }); 

     save.setText("Save"); 
     save.addActionListener(new java.awt.event.ActionListener() { 
      public void actionPerformed(java.awt.event.ActionEvent evt) { 
       saveActionPerformed(evt); 
      } 
     }); 

     jMenu1.setText("File"); 
     jMenuBar1.add(jMenu1); 

     jMenu2.setText("Edit"); 
     jMenuBar1.add(jMenu2); 

     setJMenuBar(jMenuBar1); 

     javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); 
     getContentPane().setLayout(layout); 
     layout.setHorizontalGroup(
      layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
      .addComponent(jScrollPane2) 
      .addGroup(layout.createSequentialGroup() 
       .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
        .addGroup(layout.createSequentialGroup() 
         .addGap(114, 114, 114) 
         .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 32, javax.swing.GroupLayout.PREFERRED_SIZE) 
         .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) 
         .addComponent(Date, javax.swing.GroupLayout.PREFERRED_SIZE, 77, javax.swing.GroupLayout.PREFERRED_SIZE)) 
        .addGroup(layout.createSequentialGroup() 
         .addGap(350, 350, 350) 
         .addComponent(netprofit) 
         .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) 
         .addComponent(netsum, javax.swing.GroupLayout.PREFERRED_SIZE, 75, javax.swing.GroupLayout.PREFERRED_SIZE)) 
        .addGroup(layout.createSequentialGroup() 
         .addGap(221, 221, 221) 
         .addComponent(save))) 
       .addContainerGap(147, Short.MAX_VALUE)) 
     ); 
     layout.setVerticalGroup(
      layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
      .addGroup(layout.createSequentialGroup() 
       .addGap(20, 20, 20) 
       .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) 
        .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 24, javax.swing.GroupLayout.PREFERRED_SIZE) 
        .addComponent(Date, javax.swing.GroupLayout.PREFERRED_SIZE, 29, javax.swing.GroupLayout.PREFERRED_SIZE)) 
       .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED) 
       .addComponent(jScrollPane2, javax.swing.GroupLayout.PREFERRED_SIZE, 350, javax.swing.GroupLayout.PREFERRED_SIZE) 
       .addGap(18, 18, 18) 
       .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE) 
        .addComponent(netprofit) 
        .addComponent(netsum, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)) 
       .addGap(1, 1, 1) 
       .addComponent(save) 
       .addContainerGap(32, Short.MAX_VALUE)) 
     ); 

     Date.getAccessibleContext().setAccessibleName("date"); 
     save.getAccessibleContext().setAccessibleName("save"); 

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



    private void DateActionPerformed(java.awt.event.ActionEvent evt) {          
     // TODO add your handling code here: 

    }          

    private void netprofitActionPerformed(java.awt.event.ActionEvent evt) {           
     // TODO add your handling code here: 

    }           

    private void saveActionPerformed(java.awt.event.ActionEvent evt) {          
     // TODO add your handling code here: 

     Connection conn = null; 

    Statement stmt = null; 

     int count=jTable1.getRowCount(); 
     int col=jTable1.getColumnCount(); 
     String jobno[] =new String[count]; // name is array and index 4 means no. of row 
     String item[]=new String[count]; 
     String bill[] =new String[count]; // name is array and index 4 means no. of row 
     String part[]=new String[count]; 
     String profit[] =new String[count]; // name is array and index 4 means no. of row 
     String percent[]=new String[count]; 

     for(int i=0;i<=count;i++) 
{ 
    for(int j=0;j<=col;j++) 
    { 
no[i]=jTable1.getValueAt(i,j).toString(); // it get value from 0 row and 0 column 
it[i]=jTable1.getValueAt(i,j).toString(); 
amount[i]=jTable1.getValueAt(i,j).toString(); 
p[i]=jTable1.getValueAt(i,j).toString(); 
cost[i]=jTable1.getValueAt(i,j).toString(); 
s[i]=jTable1.getValueAt(i,j).toString(); 


     try{ 

      String sql="INSERT INTO m (no,it,amount,cost,sell,p,date) VALUES('"+no[i]+"','"+it[i]+"','"+amount[i]+"','"+p[i]+"','"+cost[i]+"','"+s[i]+"','"+Date.getText()+"')"; 
      // stmt.execute(sql); 
      stmt.executeQuery(sql); 
      //stmt.execute(sql); 
      /*PreparedStatement ps=conn.prepareStatement(sql); 
      ps.setString(1, ""); 
      ps.setString(2, ""); 
      ps.setString(3, ""); 
      ps.setString(4, ""); 
      ps.setString(5, ""); 
      ps.setString(6, ""); 
      ps.setString(7,Date.getText()); 
      ps.execute();*/ 

      JOptionPane.showMessageDialog(null,"saved"); 
     } 
     catch(Exception e){ 
      JOptionPane.showMessageDialog(null,e); 
     } 
} 
    }          

    private void jTable1InputMethodTextChanged(java.awt.event.InputMethodEvent evt) {            
     // TODO add your handling code here: 
    }            

    /** 
    * @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(bill.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } catch (InstantiationException ex) { 
      java.util.logging.Logger.getLogger(bill.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } catch (IllegalAccessException ex) { 
      java.util.logging.Logger.getLogger(bill.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } catch (javax.swing.UnsupportedLookAndFeelException ex) { 
      java.util.logging.Logger.getLogger(bill.class.getName()).log(java.util.logging.Level.SEVERE, null, ex); 
     } 
     //</editor-fold> 

     Connection conn = null; 

    Statement stmt = null; 
    try{ 
     //STEP 2: Register JDBC driver 
     Class.forName("com.mysql.jdbc.Driver"); 
     //Class.forName("jdbc:mysql://localhost:3306/ganpatidb?zeroDateTimeBehavior=convertToNull"); 

     //STEP 3: Open a connection 
     System.out.println("Connecting to database..."); 
     conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ganpatidb", "root", "root"); 

     //STEP 4: Execute a query 
     System.out.println("Creating database..."); 
     stmt = conn.createStatement(); 


    }catch(SQLException se){ 
     //Handle errors for JDBC 
    // se.printStackTrace(); 
    }catch(Exception e){ 
     //Handle errors for Class.forName 
    // e.printStackTrace(); 
    }finally{ 
     //finally block used to close resources 
     try{ 
     if(stmt!=null) 
      stmt.close(); 
     }catch(SQLException se2){ 
     }// nothing we can do 
     try{ 
     if(conn!=null) 
      conn.close(); 
     }catch(SQLException se){ 
     //se.printStackTrace(); 
     }//end finally try 
    }//end try 
    //System.out.println("Goodbye!"); 

     //int r=jTable1.selectedrow; 
     //jTable1.getValue(3,3); 
     /* Create and display the form */ 
     java.awt.EventQueue.invokeLater(new Runnable() { 
      public void run() { 
       new bill().setVisible(true); 
      } 
     }); 
    } 

    // Variables declaration - do not modify      
    private javax.swing.JTextField Date; 
    private javax.swing.JLabel jLabel1; 
    private javax.swing.JMenu jMenu1; 
    private javax.swing.JMenu jMenu2; 
    private javax.swing.JMenuBar jMenuBar1; 
    private javax.swing.JScrollPane jScrollPane2; 
    private javax.swing.JTable jTable1; 
    private javax.swing.JButton netprofit; 
    private javax.swing.JTextField netsum; 
    private javax.swing.JButton save; 
    // End of variables declaration     
} 

我如何插入多行數據到MySQL數據庫.... 請幫助....

Answer 1

從它看起來，你甚至不初始化在saveActionPerformed方法下的connection和statement，你將它們設置爲NULL。

private void saveActionPerformed(java.awt.event.ActionEvent evt) {          
     // TODO add your handling code here: 

     Connection conn = null; 

    Statement stmt = null; 

在你的主要方法，但是你確實初始化他們..

try{ 
     //STEP 2: Register JDBC driver 
     Class.forName("com.mysql.jdbc.Driver"); 
     //Class.forName("jdbc:mysql://localhost:3306/ganpatidb?zeroDateTimeBehavior=convertToNull"); 

     //STEP 3: Open a connection 
     System.out.println("Connecting to database..."); 
     conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ganpatidb", "root", "root"); 

     //STEP 4: Execute a query 
     System.out.println("Creating database..."); 
     stmt = conn.createStatement(); 


    }catch(SQLException se){ 
     //Handle errors for JDBC 
     se.printStackTrace(); 
    }catch(Exception e){ 
     //Handle errors for Class.forName 
     e.printStackTrace(); 
    }finally{ 
     //finally block used to close resources 
     try{ 
     if(stmt!=null) 
      stmt.close(); 
     }catch(SQLException se2){ 
     }// nothing we can do 
     try{ 
     if(conn!=null) 
      conn.close(); 
     }catch(SQLException se){ 
     //se.printStackTrace(); 
     }//end finally try 
    }//end try 

你需要或者刪除，你將它們設置爲NULL或添加相同的代碼，然後直接和記住你需要的代碼把代碼INSIDE放在try和catch塊中。

事情是這樣的：

try{ 
    //STEP 2: Register JDBC driver 
    Class.forName("com.mysql.jdbc.Driver"); 
    //Class.forName("jdbc:mysql://localhost:3306/ganpatidb?zeroDateTimeBehavior=convertToNull"); 
    //STEP 3: Open a connection 
    System.out.println("Connecting to database..."); 
    conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/ganpatidb", "root", "root"); 
    //STEP 4: Execute a query 
    System.out.println("Creating database..."); 
    stmt = conn.createStatement(); 
    int count=jTable1.getRowCount(); 
    int col=jTable1.getColumnCount(); 
    String jobno[] =new String[count]; 
    // name is array and index 4 means no. of row 
    String item[]=new String[count]; 
    String bill[] =new String[count]; 
    // name is array and index 4 means no. of row 
    String part[]=new String[count]; 
    String profit[] =new String[count]; 
    // name is array and index 4 means no. of row 
    String percent[]=new String[count]; 
    for(int i=0; 
    i< 
    =count; 
    i++) { 
     for(int j=0; 
     j< 
     =col; 
     j++) { 
      no[i]=jTable1.getValueAt(i,j).toString(); 
      // it get value from 0 row and 0 columN 
      it[i]=jTable1.getValueAt(i,j).toString(); 
      amount[i]=jTable1.getValueAt(i,j).toString(); 
      p[i]=jTable1.getValueAt(i,j).toString(); 
      cost[i]=jTable1.getValueAt(i,j).toString(); 
      s[i]=jTable1.getValueAt(i,j).toString(); 
      try{ 
       String sql="INSERT INTO m (no,it,amount,cost,sell,p,date) VALUES('"+no[i]+"','"+it[i]+"','"+amount[i]+"','"+p[i]+"','"+cost[i]+"','"+s[i]+"','"+Date.getText()+"')"; 
       stmt.execute(sql); 
       JOptionPane.showMessageDialog(null,"saved"); 
      } 
      catch(Exception e){ 
       JOptionPane.showMessageDialog(null,e); 
      } 
     } 
     catch(SQLException se){ 
      //Handle errors for JDBC 
      se.printStackTrace(); 
     } 
     catch(Exception e){ 
      //Handle errors for Class.forName 
      e.printStackTrace(); 
     } 
     finally{ 
      //finally block used to close resources 
      try{ 
       if(stmt!=null) stmt.close(); 
      } 
      catch(SQLException se2){ 
      } 
      // nothing we can do 
      try{ 
       if(conn!=null) conn.close(); 
      } 
      catch(SQLException se){ 
       //se.printStackTrace(); 
      } 
      //end finally try 
     } 
     //end try