Java with Derby

Employee.java

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

public class Employee {
	private static int empolyeeNumber = 1;
	private int age;
	private String first, last, phone, tableName, serverName, dbName;
	
	private Connection con = null;
	private Statement stm = null;
	private ResultSet res = null;
	private PreparedStatement insertEmployee = null;
	private PreparedStatement searchEmployee = null;
	

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Employee e = new Employee();
	}

	
	public Employee(){
		serverName = "localhost";
		dbName = "EmployeeDB";
		tableName = "Employee";
		connect();
		//String insert = "insert into EmployeeDB(ID_number, firstName, lastName, phoneNumber, age) VALUES ( ?, ?, ?, ?. ?)";
		//String search = "select lastName, firstName from EmployeeDB where lastName = ? and firstName = ?";
		try {
			stm = con.createStatement();
			//insertEmployee = con.prepareStatement(insert);
			//searchEmployee = con.prepareStatement(search);
			inputData();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	
	private void inputData(){
		Scanner in = new Scanner(System.in);
		in.useDelimiter(System.getProperty("line.separator"));
		String cont = "yes", sql;
		boolean test;
		
		do{
			System.out.println("Please enter the Employee's first name:");
			first = in.next();
			System.out.println("Please enter the Employee's last name:");
			last = in.next();
			System.out.println("Please enter the Employee's phone number:");
			phone = in.next();
			System.out.println("Please enter the Employee's age:");
			age = in.nextInt();
			
			try {
				res = stm.executeQuery("select lastName, firstName from " + tableName);
				//searchEmployee.setString(1, last);
				//searchEmployee.setString(2, first);
				//res = searchEmployee.executeQuery();
				test = true;
				
				
				while(res.next()){
					if((res.getString("lastName").equals(last) && res.getString("firstName").equals(first))){
						System.out.println("You already added " + first + " " + last);
						test = false;
					}					
				}
				if(test){
					//insertEmployee.setInt(1, empolyeeNumber);
					//insertEmployee.setString(2, first);
					//insertEmployee.setString(3, last);
					//insertEmployee.setString(4, phone);
					//insertEmployee.setInt(5, age);
					//insertEmployee.executeUpdate();
					sql = "insert into Employee values (" + empolyeeNumber + ", '" + first + "' , '" + last + "' , '" +phone + "' ," +age + ")";
					stm.executeUpdate(sql);
					System.out.println("You successfully added " + first + " " + last);
					empolyeeNumber++;
				}
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			
			
			System.out.println("Would you like to continue? (yes or no)");
			cont = in.next();
			test = ((cont == "yes" || cont == "Yes" || cont == "y" || cont == "Y"));
		}while((cont == "yes" || cont == "Yes" || cont == "y" || cont == "Y"));
		
		try {
			res = stm.executeQuery("select * from Employee");
			System.out.println("ID Number   First Name    Last Name   Phone Number   Age");
			while(res.next()){
				System.out.println(res.getInt("ID_number") + "   " + res.getString("firstName") + "   " + res.getString("lastName")  + "   " + res.getString("phoneNumber") + "   " + res.getInt("age"));
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		
		close();
	}
	
	private void connect(){
		try {
			Class.forName("org.apache.derby.jdbc.ClientDriver").newInstance();
		} catch (Exception e) {
			System.out.println("No DB Drivers!");
			e.printStackTrace();
		}
		try {
			con = DriverManager.getConnection("jdbc:derby://localhost:1527/EmployeeDB");
		} catch (Exception e) {
			System.out.println("No DB connection!");
			e.printStackTrace();
		}

	}	
	
	
	public void close(){
		try {
			con.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

Errors.txt

java.sql.SQLNonTransientConnectionException: java.net.ConnectException : Error connecting to server localhost on port 1527 with message Connection refused: connect.
  at org.apache.derby.client.am.SQLExceptionFactory40.getSQLException(Unknown Source)
	at org.apache.derby.client.am.SqlException.getSQLException(Unknown Source)
	at org.apache.derby.jdbc.ClientDriver.connect(Unknown Source)
	at java.sql.DriverManager.getConnection(Unknown Source)
	at java.sql.DriverManager.getConnection(Unknown Source)
	at Employee.connect(Employee.java:91)
	at Employee.<init>(Employee.java:26)
	at Employee.main(Employee.java:18)
Caused by: org.apache.derby.client.am.DisconnectException: java.net.ConnectException : Error connecting to server localhost on port 1527 with message Connection refused: connect.
	at org.apache.derby.client.net.NetAgent.<init>(Unknown Source)
	at org.apache.derby.client.net.NetConnection.newAgent_(Unknown Source)
	at org.apache.derby.client.am.Connection.<init>(Unknown Source)
	at org.apache.derby.client.net.NetConnection.<init>(Unknown Source)
	at org.apache.derby.client.net.NetConnection40.<init>(Unknown Source)
	at org.apache.derby.client.net.ClientJDBCObjectFactoryImpl40.newNetConnection(Unknown Source)
	... 6 more
Caused by: java.net.ConnectException: Connection refused: connect
	at java.net.DualStackPlainSocketImpl.connect0(Native Method)
	at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
	at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
	at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
	at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
	at java.net.PlainSocketImpl.connect(Unknown Source)
	at java.net.SocksSocketImpl.connect(Unknown Source)
	at java.net.Socket.connect(Unknown Source)
	at java.net.Socket.connect(Unknown Source)
	at java.net.Socket.<init>(Unknown Source)
	at java.net.Socket.<init>(Unknown Source)
	at javax.net.DefaultSocketFactory.createSocket(Unknown Source)
	at org.apache.derby.client.net.OpenSocketAction.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	... 12 more
Exception in thread "main" java.lang.NullPointerException
	at Employee.<init>(Employee.java:29)
	at Employee.main(Employee.java:18)
No DB connection!

main.java

public class main {

  /**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Employee e = new Employee();
	}

}