Notes

package com;

import java.sql.*;
import java.util.*;

public class crudjdbc {

static Statement st = null;
static int id;
static Scanner scan = new Scanner(System.in);
public void addCustomer(int id, String name, String addr, int age) throws SQLException {
String s = "Select * from Customer where Cust_Id="+id;
ResultSet rs = st.executeQuery(s);
if(rs.next()) {
System.out.println("Duplicate ID! n Enter Another ID");
}else {
String add = "Insert into Customer values("+id+","+"'"+name+"'"+","+"'"+addr+"'"+","+age+")";
st.execute(add);
System.out.println("Customer Added Successfully");
}
}

public void searchCustomer() throws SQLException {
String s = "Select * from Customer where Cust_id="+id;
ResultSet rs = st.executeQuery(s);
if(rs.next()) {
System.out.println("Customer ID: "+rs.getInt("Cust_Id")+"n"+"Customer Name: "+rs.getString("Cust_Name")
+"n"+"Customer Address: "+rs.getString("Cust_Addr")+"n"+"Customer Age: "+rs.getInt("Cust_Age"));
}else {
System.out.println("Customer ID Not Exist!");
}
}

public void modifyCustomer() throws SQLException {
String s = "Select * from Customer where Cust_Id="+id;
ResultSet rs = st.executeQuery(s);
if(rs.next()) {
System.out.print("Enter Name for Update: ");
String uname = scan.next();
System.out.print("Enter Address for Update: ");
String uaddr = scan.next();
System.out.print("Enter Age for Update: ");
int uage = scan.nextInt();
String update = "Update Customer SET Cust_Name="+"'"+uname+"'"+", Cust_Addr="+"'"+uaddr+"'"+", Cust_Age="+uage+" where Cust_Id="+id;
try {
st.execute(update);
System.out.println("All Column Updated Successfully");
}catch(Exception e) {
System.out.println("Some error: "+ e);
}
}else {
System.out.println("Customer ID Not Exist");
}
}

public void deleteCustomer() throws SQLException {
String s = "Select * from Customer where Cust_Id="+id;
ResultSet rs = st.executeQuery(s);
if(rs.next()) {
String del = "Delete from Customer where Cust_Id="+id;
st.execute(del);
System.out.println("Customer Removed From Database.");
}else {
System.out.println("ID Error or it may not exists");
}
}

public void showAllCustomers() throws SQLException {
System.out.println("Showing Data............");
String show = "Select * from customer";
ResultSet rs1 = st.executeQuery(show);
System.out.println("Cust_ID"+" "+"Cust_Name"+" "+"Cust_Addr"+" "+"Cust_Age");
while(rs1.next()) {
System.out.println(rs1.getInt("Cust_Id")+" "+rs1.getString("Cust_Name")+" "+rs1.getString("Cust_Addr")+" "
+rs1.getInt("Cust_Age"));
}
}
public static void main(String[] args) {
CMSClass obj1 = new CMSClass();
try {
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/customers", "root", "");
st = con.createStatement();
while(true) {
System.out.println("Choose among the following: n 1: For Add Customer n "
+ "2: For Search Customer n 3: For Modify Customer n 4: For Delete Customer n "
+ "5: For Show Customer n 6: For Exit");
int a = scan.nextInt();
if(a==1) {
System.out.print("Enter Customer ID: ");
id = scan.nextInt();
System.out.print("Enter Name of Customer: ");
String name = scan.next();
System.out.print("Enter Address of Customer: ");
String addr = scan.next();
System.out.print("Enter Age of Customer: ");
int age = scan.nextInt();
obj1.addCustomer(id, name, addr, age);
}else if(a==2) {
System.out.println("Enter Customer ID: ");
id = scan.nextInt();
obj1.searchCustomer();
}else if(a==3) {
System.out.println("Enter Customer ID: ");
id = scan.nextInt();
obj1.modifyCustomer();
}else if(a==4) {
System.out.println("Enter Customer ID: ");
id = scan.nextInt();
obj1.deleteCustomer();
}else if(a==5) {
obj1.showAllCustomers();
}else if(a==6) {
System.out.println("Thanks For using!");
System.out.println("Byy.......Meet u Next time");
break;
}else {
System.out.println("Wrong Choice");
}
}
}catch(Exception e) {
System.out.println("Some Error "+e);
}

}

}