package zain;
import java.awt.GridLayout;
import java.awt.HeadlessException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
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.logging.Level;
import java.util.logging.Logger;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;

public class usingDB extends JFrame implements ActionListener {
    JLabel l1, l2, l3;
    JButton b1, b2, b3;
    JTextField t1, t2, t3;
    JPanel p1, p2, p3, connPanel;
    Connection conn;
    Statement st;
    String connString;
      ResultSet rs;
    public usingDB() {
        l1 = new JLabel("Employee ID :");
        l2 = new JLabel("Employee name :");
        l3 = new JLabel("Employee Salary :");
        b1 = new JButton("get data");
        b2 = new JButton("connect");
        b3 = new JButton("close");
        t1 = new JTextField(20);
        t2 = new JTextField(20);
        t3 = new JTextField(20);
        p1 = new JPanel(new GridLayout(1, 2, 5, 5));
        p2 = new JPanel(new GridLayout(1, 2, 5, 5));
        p3 = new JPanel(new GridLayout(1, 2, 5, 5));
        connPanel = new JPanel(new GridLayout(1, 2, 5, 5));
        p1.add(l1);
        p1.add(t1);
        p2.add(l2);
        p2.add(t2);
        p3.add(l3);
        p3.add(t3);
        connPanel.add(b2);
        connPanel.add(b3);
        b3.setEnabled(false);
        b1.setEnabled(false);
        setLayout(new GridLayout(5, 1));
        add(p1);
        add(b1);
        add(p2);
        add(p3);
        add(connPanel);
        b1.addActionListener(this);
        b2.addActionListener(this);
        b3.addActionListener(this);
        setSize(400, 400);
        setTitle("Example");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);
        setLocationRelativeTo(null);
    }

    public static void main(String[] args) {
        usingDB info = new usingDB();
    }

    @Override
    public void actionPerformed(ActionEvent ae) {
        if (ae.getSource() == b2) {
            b2.setEnabled(false);
            b3.setEnabled(true);
            b1.setEnabled(true);
            try {
                Class.forName ("oracle.jdbc.driver.OracleDriver");
               connString = "jdbc:oracle:thin:localhost:1521:XE";
                conn = DriverManager.getConnection(connString, "System", "12345");
                st = conn.createStatement();
            } catch (ClassNotFoundException | SQLException ex) {
                ex.printStackTrace();
            }

        } else if (ae.getSource() == b3) {
            b2.setEnabled(true);
            b3.setEnabled(false);
            b1.setEnabled(false);

            try {
                conn.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }

        } else if (ae.getSource() == b1) {
            try {
                String students = "select ENAME , sal from emp where empno = " + t1.getText();
                rs = st.executeQuery(students);
                if (rs.next()) {
                    t2.setText(rs.getString(1));
                    t3.setText(rs.getString(2));
                }

            } catch (SQLException sqle) {
                sqle.printStackTrace();

            }

        }

    }
}