The document contains Java code snippets demonstrating database connectivity with JDBC for basic CRUD operations: insert, search, delete, update, and display data in a table. Each section includes methods for handling user input, managing SQL queries, and providing feedback through dialog messages. Error handling is also addressed throughout the code to manage SQL exceptions.

2.  Insert Program UsingDatabaseConnectivity
Coding:
importcom.mysql.jdbc.Connection;
importcom.mysql.jdbc.Statement;
importjava.sql.DriverManager;
importjavax.swing.JOptionPane;
importjava.lang.Math;
private voidjButton2ActionPerformed(java.awt.event.ActionEventevt) {
name.setText("");
mob.setText("");
email.setText("");
}
private void jButton3ActionPerformed(java.awt.event.ActionEventevt) {
System.exit(0);
}
private void jButton1ActionPerformed(java.awt.event.ActionEventevt) {
Stringnam, mail ;
Stringmobile ;

3. inti = (int) (Math.random()*10);
nam= name.getText();
mail=email.getText();
mobile =mob.getText();
try
{
Class.forName("java.sql.DriverManager");
Connectioncom=(Connection)
DriverManager.getConnection
("jdbc:mysql://localhost:3306/himanshi","root","himanshi");
Statementstmt= (Statement) com.createStatement();
Stringquery= "INSERT INTOCONTACTVALUES ('"+i+"','"+nam+"','"+mobile+"','"+mail+"');";
stmt.executeUpdate(query);
JOptionPane.showMessageDialog(this,"Yourcontacthas beensaved"+ i);
}
catch(Exceptione)
{
JOptionPane.showMessageDialog(this,e.getMessage());
}
}

4.  SearchProgram usingJDBC

5. CODING:
import com.mysql.jdbc.Connection;
import com.mysql.jdbc.Statement;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JOptionPane;
private voidjButton3ActionPerformed(java.awt.event.ActionEventevt){
System.exit(0);
}
private void jButton2ActionPerformed(java.awt.event.ActionEventevt) {
mob.setText("");
name.setText("");
email.setText("");
}
private void jButton1ActionPerformed(java.awt.event.ActionEventevt) {
Stringmobile;
mobile =mob.getText();
name.setEditable(false);
email.setEditable(false);
try
{
Class.forName("java.sql.DriverManager");
Connectioncom=(Connection)
DriverManager.getConnection("jdbc:mysql://localhost:3306/himanshi","root","himanshi");
Statementstmt=(Statement)com.createStatement();
Stringquery= "SELECT NAME , EMAIL FROMCONTACTWHERE MOBILE = '"+mobile+"';";
ResultSetrs=stmt.executeQuery(query);//ResultSetisadatatype & rs isvariable whichstore
queryof mysql
if (rs.next())
{
StringName = rs.getString("Name");
StringEmail = rs.getString("Email");
name.setText(Name);
email.setText(Email);
}
else
JOptionPane.showMessageDialog(this,"Sorry!NosuchMobile No");
}
catch(Exceptione)

6. {
JOptionPane.showMessageDialog(this,e.getMessage());
}
}
private void formWindowOpened(java.awt.event.WindowEventevt) {
name.setEditable(false);
email.setEditable(false);
}

7.  DELETEPROGRAMUSING JDBC
CODING:
importcom.mysql.jdbc.Connection;
importcom.mysql.jdbc.Statement;
importjava.sql.DriverManager;
importjava.sql.ResultSet;
importjavax.swing.JOptionPane;
private voidjButton4ActionPerformed(java.awt.event.ActionEventevt){
mob.setText("");
}
private void jButton6ActionPerformed(java.awt.event.ActionEventevt) {
System.exit(0);
}
private void jButton1ActionPerformed(java.awt.event.ActionEventevt) {
Stringmobile ;
mobile =mob.getText();
introw;
try
{
Class.forName("java.sql.DriverManager");
Connectioncom=(Connection)
DriverManager.getConnection("jdbc:mysql://localhost:3306/himanshi","root","himanshi");
Statementstmt=(Statement)com.createStatement();
Stringquery= "DELETE FROM CONTACTWHERE MOBILE = '"+mobile+"';";

8. intr = stmt.executeUpdate(query);
System.out.println(r);
if (r>0)
{
JOptionPane.showMessageDialog(this,"YOURCONTACTHAS BEEN DELETED") ;
}
else
{
JOptionPane.showMessageDialog(this,"Sorry!nosuchmobile");
}
}
catch(Exceptione)
{
JOptionPane.showMessageDialog(this,e.getMessage());
}
}

9.  UPDATEUSINGJDBC
CODING:
importcom.mysql.jdbc.Connection;
importcom.mysql.jdbc.Statement;
importjava.sql.DriverManager;
importjavax.swing.JOptionPane;
private voidjButton2ActionPerformed(java.awt.event.ActionEventevt) {
name.setText("");
mob.setText("");
email.setText("");
}
private void jButton1ActionPerformed(java.awt.event.ActionEventevt) {
Stringnam, mail ,mobile ;;
nam= name.getText();

10. mail=email.getText();
mobile =mob.getText();
intID=Integer.parseInt(id.getText());
try
{
Class.forName("java.sql.DriverManager");
Connection
com=(Connection)DriverManager.getConnection("jdbc:mysql://localhost:3306/contact","root","himans
hi");
Statementstmt= (Statement) com.createStatement();
Stringquery= "Update Contactset Name='"+nam+"', Email = '"+mail+"', Mobile = '"+mobile+"'
where S_No='"+ID+"';";
introwsEffected=stmt.executeUpdate(query);
}
catch(Exceptione)
{
JOptionPane.showMessageDialog(this,e.getMessage());
}
}
private void jButton3ActionPerformed(java.awt.event.ActionEventevt) {
System.exit(0);
}

11.  DISPLAYIN TABLEUSING JDBC
CODING:
importcom.mysql.jdbc.Connection;
importcom.mysql.jdbc.Statement;
importjava.sql.DriverManager;
importjava.sql.ResultSet;
importjava.sql.SQLException;
importjavax.swing.JOptionPane;
importjavax.swing.table.DefaultTableModel;

12. private voidjButton1ActionPerformed(java.awt.event.ActionEventevt) {
DefaultTableModel model =(DefaultTableModel)
table.getModel();
try
{
Class.forName("java.sql.DriverManager");
Connectioncon= (Connection)
DriverManager.getConnection("jdbc:mysql://localhost:3306/himanshi","root","himanshi");
Statementstmt= (Statement)con.createStatement();
StringTname;
if (personal.isSelected())
Tname="Contact";
else
Tname="Official";
Stringquery= "SELECT * FROM "+Tname+";";
ResultSetrs= stmt.executeQuery(query);
while (rs.next())
{
StringName = rs.getString("Name");
StringMobile = rs.getString("Mobile");
StringEmail=rs.getString("Email");
model.addRow(new Object[]{Name,Mobile ,Email});
}
}
catch(Exceptione)
{
JOptionPane.showMessageDialog(this,e.getMessage());
}
}
private void jButton3ActionPerformed(java.awt.event.ActionEventevt) {
System.exit(0);
}
private void jButton2ActionPerformed(java.awt.event.ActionEventevt) {
DefaultTableModel model =(DefaultTableModel)
table.getModel();
introw=model.getRowCount();

13. if (row>0)
{
for(inti=0; i<row;i++ )
model.removeRow(0);
}