j10

/*
2. Write a Java program to display first record from student table (RNo, SName, Per) onto
the TextFields by clicking on button. (Assume Student table is already created)
*/
package com.mycompany.javaslip;

import java.awt.GridLayout;
import java.sql.;
import java.util.logging.;
import javax.swing.*;

class StudentRec
{
private JFrame frame;
private JTextField tf1, tf2, tf3;
private JButton display;

StudentRec() throws SQLException {
    frame = new JFrame("Student First Record.");
    frame.setSize(200, 300);
    
    tf1 = new JTextField();
    tf2 = new JTextField();
    tf3 = new JTextField();
    
    display = new JButton("Show Record");
    
    Connection conn = DriverManager.getConnection("jdbc:postgresql://localhost:5432/postgres", "postgres", "postgres");
    
    display.addActionListener((ActionEvent) -> {
        try {
            select(conn);
        } catch (SQLException ex) {
            Logger.getLogger(StudentRec.class.getName()).log(Level.SEVERE, null, ex);
        }
    });
    
    frame.setLayout(new GridLayout(4,1));
    
    frame.add(tf1);
    frame.add(tf2);
    frame.add(tf3);
    frame.add(display);
    
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
}

private void select(Connection conn) throws SQLException {
    String sql = "select * from student where rno = 1";
    
    Statement stmt = conn.createStatement();
    stmt.executeQuery(sql);
    ResultSet rs = stmt.getResultSet();
    
    while(rs.next()) {
        tf1.setText("       " + rs.getInt("rno"));
        tf2.setText("      " + rs.getString("sname"));
        tf3.setText("      "  + rs.getFloat("per") + "");
    }
}

}

public class slip10_2
{
public static void main(String[] args) throws SQLException {
new StudentRec();
}
}