cz.muni.pa165.carparkapp.DAOImpl.EmployeeDAOImpl.java Source code

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Here is the source code for cz.muni.pa165.carparkapp.DAOImpl.EmployeeDAOImpl.java

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package cz.muni.pa165.carparkapp.DAOImpl;

import cz.muni.pa165.carparkapp.DAO.EmployeeDAO;
import cz.muni.pa165.carparkapp.Entities.Employee;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import javax.transaction.Transactional;
import org.apache.commons.lang3.Validate;
import org.springframework.dao.DataAccessException;
import org.springframework.stereotype.Repository;

/**
 *
 * @author Martin Lisy, 396280
 */

@Repository("employeeDAO")
@Transactional
public class EmployeeDAOImpl implements EmployeeDAO {

    @PersistenceContext
    private EntityManager em;

    public EmployeeDAOImpl() {
    }

    public void setEm(EntityManager em) {
        this.em = em;
    }

    public EntityManager getEm() {
        return em;
    }

    @Override
    public List<Employee> getAllEmployees() {
        List<Employee> employees = null;
        try {
            employees = em.createQuery("SELECT e FROM Employee e", Employee.class).getResultList();
        } catch (Exception e) {
            throw new DataAccessException("Exception during getting Employees from DB") {
            };
        }
        return employees;
    }

    @Override
    public Employee findEmployeeById(int id) {
        Validate.isTrue(id > 0, "Employees's ID cannot be null!");
        Query query = em.createQuery("select e from Employee e " + "where e.id = ?1").setParameter(1, id);

        if (query.getResultList() == null) {
            throw new IllegalArgumentException("Error in query during employee finding");
        }
        if (query.getResultList().size() != 1) {
            throw new IllegalArgumentException("No such employee was found");
        }

        return ((List<Employee>) query.getResultList()).get(0);
    }

    @Override
    public boolean updateEmployee(Employee employee) {
        Validate.isTrue(employee != null, "Employee cannot be null!");
        Validate.isTrue(employee.getId() != -1, "Employee's ID cannot be null!");
        em.merge(employee);
        return true;
    }

    @Override
    public boolean deleteEmployee(Employee employee) {
        Validate.isTrue(employee != null, "Employee cannot be null!");
        Validate.isTrue(employee.getId() != -1, "Employee's ID cannot be null!");
        em.remove(em.merge(employee));
        return true;
    }

    @Override
    public Employee addEmployee(Employee employee) {
        Validate.isTrue(employee != null, "Employee cannot be null!");
        em.persist(employee);
        return employee;

    }
}