07U4QeZq

1import java.sql.Connection;
2import java.sql.DriverManager;
3import java.sql.PreparedStatement;
4import java.sql.ResultSet;
5import java.util.Scanner;
6
7public class test {
8	
9	public static void main(String args[]){
10		try{
11			createTable();
12			Scanner scan = new Scanner(System.in);
13			System.out.println("enter username");
14			String username = scan.nextLine();
15			if(createAccount(username)){
16				System.out.println("valid, account created");
17			}else{
18				System.out.println("username taken");
19			}
20		}catch(Exception e){
21			System.out.println(e.getMessage());
22		}
23	}
24	
25	public static boolean createAccount(String username) throws Exception{
26		try{
27			Connection con = getConnection();
28			PreparedStatement statement = con.prepareStatement("SELECT * FROM users WHERE username='" + username + "';");
29			System.out.println(statement);
30			ResultSet result = statement.executeQuery();
31			if(result.next())
32				return false;
33			else{
34				insert(username, "test", "arjun", "narayan");
35				return true;
36			}
37		}catch(Exception e){
38			System.out.println(e.getMessage());
39		}
40		return false;
41	}
42	
43	public static void insert(String username, String password, String fname, String lname) throws Exception{
44		try{	
45			Connection con = getConnection();
46			PreparedStatement inserted = con.prepareStatement("INSERT INTO users(username, password, fname, lname) VALUES "
47					+ "('"+ username +"', '"+ password + "', '" + fname + "', '" + lname + "')");  
48			System.out.println(inserted.toString());
49			inserted.executeUpdate();	
50		}catch(Exception e){
51			System.out.println(e.getMessage());
52		}finally{
53			System.out.println("insert worked");
54		}
55	}
56	
57	public static void createTable() throws Exception{
58		try{
59			Connection con = getConnection();
60			PreparedStatement create = con.prepareStatement("CREATE TABLE IF NOT EXISTS "
61					+ "users(userId int NOT NULL AUTO_INCREMENT, username varchar(250), "
62					+ "password varchar(250), fname varchar(250), lname varchar(250), PRIMARY KEY(userId))");
63			create.executeUpdate();
64			
65		}catch(Exception e){
66			System.out.println(e.getMessage());
67		}finally{
68			System.out.println("table has been created or function complete.");
69		}
70	}
71	
72	public static Connection getConnection() throws Exception{
73		try{
74			String driver = "com.mysql.jdbc.Driver";
75			//localhost (change IP if not)
76			String url = "jdbc:mysql://127.0.0.1:3306/test_schema";
77			String user = "root";
78			String password = "x5bhsmn7*";
79			Class.forName(driver);
80			Connection conn = DriverManager.getConnection(url, user, password);
81			System.out.println("connection successful.");
82			return conn;
83		}catch(Exception e){
84			System.out.println(e.getMessage());
85		}
86		return null;
87	}
88}