Jdbcjdbc:odbc

[kokoriko]

Hallo an Alle
Ich habe ein Link hier bekommen und es geht um Access und Java aber die Verbindung klappt nur ich kriege keine Daten aus der JTable ..

Ich habe 1 Frage muss man den jdbcdbc installiert haben oder?

den code habe ich von hier bekommen aber den datenbanksnamen habe ich anders gennant :


/*
* JTableExample.java
*
* Created on 24. September 2007, 10:34
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/

package tableaccess;

/**
*
* @author Jean
*/
import java.sql.*;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Arrays;
import java.util.Vector;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.table.DefaultTableModel;


/**
* @author Darimont<br>
* @version 1.0<br>
* Date of creation: 10.03.2004<br>
* File: JTableExample.java<br>
* Modifier: Darimont<br>
* Revision: Revision<br>
* State: Germany<br>
*/

public class JTableExample extends JFrame {

private static final String dbDriverClass = "sun.jdbc.odbc.JdbcOdbcDriver";

static {
try {

Thread
.currentThread()
.getContextClassLoader()
.loadClass(dbDriverClass)
.newInstance();
} catch (InstantiationException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (IllegalAccessException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();

} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

private JButton btnConnect, btnRefresh;
private JTextField txtSQL;
private JTable table;
private JScrollPane scrollPane;
private DefaultTableModel dtm;
private javax.swing.JPanel btnPanel, contentPanel;

private final String dbPath =
"H:/JC/DATENBANKFONDS.mdb";
//private final String dbUser = "Administrator";
private final String dbUser = " ";
private final String dbpasswd = "";
//Leerzeichen zwischen : und D entfernen...
private final String dbURL =
"jdbcdbc: DRIVER={Microsoft Access Driver (*.mdb)};DBQ=" + dbPath;


private Connection con;
private ResultSet rs;

public JTableExample() {
super("JTableExample");

GridBagConstraints gridBagConstraints;

contentPanel = new JPanel();
btnPanel = new JPanel();
btnConnect = new JButton();
btnRefresh = new JButton();
txtSQL = new JTextField();
scrollPane = new JScrollPane();
table = new JTable();
dtm = new DefaultTableModel();

getContentPane().setLayout(new FlowLayout());

setTitle("JTableExample");
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent evt) {
try {
if (con != null && !con.isClosed()) {
con.close();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
setVisible(false);
dispose();
System.exit(0);
}
});

contentPanel.setLayout(new GridBagLayout());

contentPanel.setBackground(new Color(102, 153, 255));
contentPanel.setMinimumSize(new Dimension(400, 300));
contentPanel.setPreferredSize(new Dimension(400, 300));
btnPanel.setBackground(new Color(255, 153, 51));
btnPanel.setMinimumSize(new Dimension(400, 100));
btnPanel.setPreferredSize(new Dimension(400, 100));
btnConnect.setText("Connect");
btnPanel.add(btnConnect);

btnRefresh.setText("Refresh");
btnPanel.add(btnRefresh);

txtSQL.setColumns(25);
btnPanel.add(txtSQL);

gridBagConstraints = new GridBagConstraints();
gridBagConstraints.gridx = 0;
gridBagConstraints.gridy = 1;
contentPanel.add(btnPanel, gridBagConstraints);

scrollPane.setMinimumSize(new Dimension(400, 200));
scrollPane.setPreferredSize(new Dimension(400, 200));
table.setModel(dtm);
table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
scrollPane.setViewportView(table);

contentPanel.add(scrollPane, new GridBagConstraints());

getContentPane().add(contentPanel);

setSize(400, 300);

Container container = getContentPane();
btnConnect.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
connect();
}

});
btnRefresh.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
refresh();
}

});

setVisible(true);
}

/**
*
*/
protected void refresh() {
// TODO Auto-generated method stub
try {
if (con == null || con.isClosed()) {
JOptionPane.showMessageDialog(
this,
"Keine Datenbaknverbindung!",
"Fehler",
JOptionPane.ERROR_MESSAGE);
return;
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

Statement stmt = null;
try {
stmt = con.createStatement();
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}

if (stmt == null) {
throw new RuntimeException("stmt is null");
}

String sql = txtSQL.getText();
if (sql == null) {
JOptionPane.showMessageDialog(
this,
"Keine SQL Abfrage angegeben!",
"Fehler",
JOptionPane.ERROR_MESSAGE);
return;
}
try {
rs = stmt.executeQuery(sql);

} catch (SQLException e2) {
// TODO Auto-generated catch block
e2.printStackTrace();
}

putRSinTableModel(rs, dtm);

table.setModel(dtm);

table.updateUI();

}

/**
* @param rs
* @param dtm
*/
private void putRSinTableModel(ResultSet rs, DefaultTableModel dtm) {
// TODO Auto-generated method stub
ResultSetMetaData rsmd = null;
int clmCnt = -1;
try {
rsmd = rs.getMetaData();
clmCnt = rsmd.getColumnCount();

} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

if (rsmd == null || clmCnt == -1) {
throw new RuntimeException("rsmd is null");
}
try {

Object[] clmHeaders = new Object[clmCnt];
for (int i = 1; i <= clmCnt; i++) {
clmHeaders[i - 1] = rsmd.getColumnName(i);
}

Vector rows = new Vector();
Vector rowData = null;

int row = 0;
while (rs.next()) {
rowData = new Vector();
for (int i = 1; i <= clmCnt; i++) {
String fieldVal = rs.getString(i);
System.out.print(fieldVal + " ");
rowData.add(fieldVal);
}
rows.add(rowData);
System.out.println();
}
dtm.setDataVector(rows, new Vector(Arrays.asList(clmHeaders)));
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}

}

/**
*
*/
protected void connect() {
// TODO Auto-generated method stub
if (con != null)
return;
System.out.println(dbURL);
try {
con = DriverManager.getConnection(dbURL, dbUser, dbpasswd);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}

public static void main(String[] args) {
new JTableExample();
}
}

 

[Vatar]

Wenn ich micht entsinne ist der odbc-Treiber dabei, nur bei anderen (richtigen) Datenbanken musst du den extra hinzufügen. Außerdem ist die odbc-Brücke recht langsam aber im Falle von Access ist das schon korrekt.

Ich sehe in diesem "Code" keinerlei SELECT. Wenn du ein Ergebnis aus der DB haben willst musst du eine SQL-Abfrage formulieren (wobei der Access-Dialect ein wenig vom Standard abweicht).

Connection con = ....  // eine Connection hast du ja
Statement stmt = con.createStatement();
ResultSet result = stmt.executeQuery("SELECT * FROM tablename");
while (result.next){
   // Hier hast du dann jeweils eine Zeile/Datensatz zum verarbeiten
}
// wird gern vergessen
stmt.close();
con.close();

Im Netzt findet man hunderte dieser Beispiele