empServices.java

import java.sql.*;
import java.util.*;
import java.util.logging.Logger;
import java.util.stream.Collectors;

public class empServices {
    static final connectionClass sqlConnector = new connectionClass();
    static final Logger logger = Logger.getLogger(empServices.class.getName());

    public void insertIntoTable(ArrayList<Employee> employees) {
        PreparedStatement ps = null;
        String insertQuery = "INSERT INTO employe(name, age, dept, location) VALUES (?, ?, ?, ?)";

        try {
            ps = sqlConnector.createPrepareStatement(insertQuery);
            for (Employee e : employees) {
                ps.setString(1, e.name);
                ps.setInt(2, e.age);
                ps.setString(3, e.dept);
                ps.setString(4, e.location);
                ps.executeUpdate();
            }
        } catch (SQLException e1) {
            e1.printStackTrace();
        } finally {
            try {
                if (ps != null) ps.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        }
    }

    public List<Employee> selectFromTable() {
        List<Employee> Emp_Data_Db = new ArrayList<>();
        Statement st = null;
        ResultSet rs = null;

        try {
            st = sqlConnector.createStatement();
            rs = st.executeQuery("SELECT * FROM employe");

            while (rs.next()) {
                Employee e = new Employee(
                        rs.getInt("emp_id"),
                        rs.getString("name"),
                        rs.getInt("age"),
                        rs.getString("dept"),
                        rs.getString("location")
                );
                Emp_Data_Db.add(e);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            try {
                if (rs != null) rs.close();
                if (st != null) st.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        }

        return Emp_Data_Db;
    }

    public void arraySortComparator(List<Employee> employees) {
        logger.info("Sorted by Name (Comparator):");
        employees.sort(Comparator.comparing(emp -> emp.name.toLowerCase()));
        employees.forEach(e -> logger.info(e.toString()));
    }

    public List<Employee> getNoidaEmp(List<Employee> employees) {
        System.out.println("Employees in Noida (using Stream API):");
        return employees.stream()
                .filter(e -> e.location.equalsIgnoreCase("Noida"))
                .collect(Collectors.toList());
    }

    public void closeService() {
        sqlConnector.closeConnection();
    }
}