
Hii Sir, I am developing a swing app for adding,updating and deleting from jtable cells to database but i am getting following problems
Whenever i click on delete button on selecting particular row which has to be deleted then last row is getting removed from the jtable but selected row is getting deleted from the database . I want to remove and delete the same row which is selected for the dletion.
updation is happening for state column only and not happening for id,First name,Last name etc..
My Database column structure is :presid(int),firstname(varchar),last name(varchar),state(varchar),date(date).
plz sir help me to solve this problem.I am posting my code. Thanx in advance.
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import java.awt.BorderLayout; import java.awt.Font; import java.awt.event.ActionEvent; import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent;
import java.sql.*; import java.text.ParseException;
import java.text.SimpleDateFormat;
import javax.swing.*; import javax.swing.table.DefaultTableModel;
public class Lesson38 extends JFrame {
static JLabel lFirstName, lLastName, lState, lBirthDate;
static JTextField tfFirstName, tfLastName, tfState, tfBirthDate;
static java.util.Date dateBirthDate, sqlBirthDate;
static ResultSet rows;
// Holds row values for the table
static Object[][] databaseResults;
// Holds column names for the table
static Object[] columns = {"ID", "First Name", "Last Name", "State", "Birth Date"};
// DefaultTableModel defines the methods JTable will use
// I'm overriding the getColumnClass
static DefaultTableModel dTableModel = new DefaultTableModel(databaseResults, columns) {
public Class getColumnClass(int column) {
Class returnValue;
// Verifying that the column exists (index > 0 && index < number of columns
if ((column >= 0) && (column < getColumnCount())) {
returnValue = getValueAt(0, column).getClass();
} else {
// Returns the class for the item in the co6lumn
returnValue = Object.class;
}
return returnValue;
}
};
// Create a JTable using the custom DefaultTableModel
static JTable table = new JTable(dTableModel);
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// A connection object is used to provide access to a database
Connection conn = null;
try {
// The driver allows you to query the database with Java
// forName dynamically loads the class for you
Class.forName("com.mysql.jdbc.Driver");
// DriverManager is used to handle a set of JDBC drivers
// getConnection establishes a connection to the database
// You must also pass the userid and password for the database
conn = DriverManager.getConnection("jdbc:mysql://localhost/techsoft", "root", "techsoft");
// Statement objects executes a SQL query
// createStatement returns a Statement object
Statement sqlState = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
ResultSet.CONCUR_UPDATABLE);
// This is the query I'm sending to the database
String selectStuff = "Select pres_id, first_name, last_name, state, birth from president";
// A ResultSet contains a table of data representing the
// results of the query. It can not be changed and can
// only be read in one direction
rows = sqlState.executeQuery(selectStuff);
// Temporarily holds the row results
Object[] tempRow;
// next is used to iterate through the results of a query
while (rows.next()) {
tempRow = new Object[]{rows.getInt(1), rows.getString(2), rows.getString(3), rows.getString(4), rows.getDate(5)};
/*
* You can also get other types 124 * int getInt() 125 * boolean
* getBoolean() 126 * double getDouble() 127 * float getFloat()
* 128 * long getLong() 129 * short getShort() 130
*/
// Add the row of data to the JTable
dTableModel.addRow(tempRow);
}
} catch (SQLException ex) {
// String describing the error
System.out.println("SQLException: " + ex.getMessage());
// Vendor specific error code
System.out.println("VendorError: " + ex.getErrorCode());
} catch (ClassNotFoundException e) {
// Executes if the driver can't be found
e.printStackTrace();
}
// Increase the font size for the cells in the table
table.setFont(new Font("Serif", Font.PLAIN, 15));
// Increase the size of the cells to allow for bigger fonts
table.setRowHeight(table.getRowHeight() + 12);
// Allows the user to sort the data
table.setAutoCreateRowSorter(true);
// Adds the table to a scrollpane
JScrollPane scrollPane = new JScrollPane(table);
// Adds the scrollpane to the frame
frame.add(scrollPane, BorderLayout.CENTER);
// Creates a button that when pressed executes the code
// in the method actionPerformed
JButton addPres = new JButton("Add President");
addPres.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String sFirstName = "", sLastName = "", sState = "", sDate = "";
// getText returns the value in the text field
sFirstName = tfFirstName.getText();
sLastName = tfLastName.getText();
sState = tfState.getText();
sDate = tfBirthDate.getText();
sqlBirthDate = getADate(sDate);
try {
// Moves the database to the row where data will be placed
rows.moveToInsertRow();
// Update the values in the database
rows.updateString("first_name", sFirstName);
rows.updateString("last_name", sLastName);
rows.updateString("state", sState);
rows.updateDate("birth", (Date) sqlBirthDate);
// Inserts the changes to the row values in the database
rows.insertRow();
// Directly updates the values in the database
rows.updateRow();
} catch (SQLException e1) {
e1.printStackTrace();
}
int presID = 0;
try {
// Go to the last row inserted and get the id
rows.last();
presID = rows.getInt(1);
} catch (SQLException e1) {
e1.printStackTrace();
}
Object[] president = {presID, sFirstName, sLastName, sState, sqlBirthDate};
// Add the row of values to the JTable
dTableModel.addRow(president);
}
});
JButton removePres = new JButton("Remove President");
removePres.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// Will remove which ever row that is selected
dTableModel.removeRow(table.getSelectedRow()+1);
System.out.println(table.getSelectedRow());
try {
// Moves the database to the row currently selected
// getSelectedRow returns the row number for the selected row
rows.absolute(table.getSelectedRow()+1);
// Deletes the selected row from the database
System.out.println(table.getSelectedRow());
rows.deleteRow();
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
});
// Define values for my labels
lFirstName = new JLabel("First Name");
lLastName = new JLabel("Last Name");
lState = new JLabel("State");
lBirthDate = new JLabel("Birthday");
tfFirstName = new JTextField(15);
tfLastName = new JTextField(15);
tfState = new JTextField(15);
// Set default text and size for text field
tfBirthDate = new JTextField("yyyy-MM-dd", 10);
// Create a panel to hold editing buttons and fields
JPanel inputPanel = new JPanel();
// Put components in the panel
inputPanel.add(lFirstName);
inputPanel.add(tfFirstName);
inputPanel.add(lLastName);
inputPanel.add(tfLastName);
inputPanel.add(lState);
inputPanel.add(tfState);
inputPanel.add(lBirthDate);
inputPanel.add(tfBirthDate);
inputPanel.add(addPres);
inputPanel.add(removePres);
// Add the component panel to the frame
frame.add(inputPanel, BorderLayout.SOUTH);
// When the user clicks on a cell they'll be able to change the value
table.addMouseListener(new MouseAdapter() {
public void mouseReleased(MouseEvent me) {
String value = JOptionPane.showInputDialog(null, "Enter Cell Value:");
// Makes sure a value is changed only if OK is clicked
if (value != null) {
table.setValueAt(value, table.getSelectedRow(), table.getSelectedColumn());
}
try {
// Move to the selected row
rows.absolute(table.getSelectedRow() + 1);
// Get the name of the selected column
String updateCol = dTableModel.getColumnName(table.getSelectedColumn());
System.out.println(updateCol);
// Previous to Java 1.7 you couldn't use Strings in a Switch
// If you get an error here it is because you aren't using Java 1.7
switch (updateCol) {
// Uses a different update method depending on the data type
case "birth":
sqlBirthDate = getADate(value);
rows.updateDate(updateCol, (Date) sqlBirthDate);
rows.updateRow();
break;
default:
rows.updateString(updateCol, value);
System.out.println("Current Row: " + rows.getRow());
System.out.println(value);
rows.updateRow();
break;
}
} catch (SQLException e) {
// Commented out so the user can delete rows
// e.printStackTrace(); }
}
}
});
frame.setSize(1200, 500);
frame.setVisible(true);
}
// Will convert from string to date
public static java.util.Date getADate(String sDate) {
SimpleDateFormat dateFormatter = new SimpleDateFormat("yyyy-MM-dd");
try {
dateBirthDate = dateFormatter.parse(sDate);
sqlBirthDate = new java.sql.Date(dateBirthDate.getTime());
} catch (ParseException e1) {
e1.printStackTrace();
}
return sqlBirthDate;
}
} `
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