JPA /DTO

?xml version="1.0" encoding="UTF-8"?
persistence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
  version="2.0" xmlns="http://java.sun.com/xml/ns/persistence"
 
  persistence-unit name="myp" transaction-type="RESOURCE_LOCAL" 
  provider    org.eclipse.persistence.jpa.PersistenceProvider         /provider 

    class>com.emp.entity.Department

    class>com.emp.entity.Employee
    class>com.emp.entity.Manager
    class>com.emp.entity.EmployeeManager
    class>com.emp.entity.EmployeeManagerPK
   
    properties
      property name="eclipselink.jdbc.driver" value="org.postgresql.Driver"       property name="eclipselink.jdbc.url" value="jdbc:postgresql://127.0.0.1:5432/employee"
      property name="eclipselink.jdbc.user" value="postgres"
      property name="eclipselink.jdbc.password" value="allion123"
     
     
   
 



---------------------------------------------

package com.company.entity;

import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;

@Entity
public class Department {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private String id ;
  
    @Column(length=25 ,nullable=false)
    private String name ;
  
    @OneToMany(fetch = FetchType.LAZY ,mappedBy = "department")
    @JoinColumn(name = "department", nullable = true)
    private Set managers ;
  

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Set getManagers() {
        return managers;
    }

    public void setManagers(Set managers) {
        this.managers = managers;
    }

}

---------------------------------------------------

package com.company.entity;

import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
import javax.persistence.OneToMany;


@Entity
public class Employee {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(length=10, nullable =false)
    private String id;
   
    @Column(length=20, nullable =true)
    private String name;
   
    @Column(length=9, nullable =false)
    private String nic;
   
    /*@ManyToMany(cascade=CascadeType.ALL, fetch=FetchType.LAZY)
    @JoinTable(name="employee_manager" ,joinColumns =@JoinColumn(name ="id") ,inverseJoinColumns=@JoinColumn(name ="mid") )
    private Set managers;*/
   
    @OneToMany(fetch = FetchType.LAZY ,mappedBy = "employee_id")
    @JoinColumn(name = "employee_id", nullable = true)
    private Set em;
   
   
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getNic() {
        return nic;
    }
    public void setNic(String nic) {
        this.nic = nic;
    }
   
    public Set getEm() {
        return em;
    }
    public void setEm(Set em) {
        this.em = em;
    }
   
}
---------------------------------------------

package com.company.entity;

import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;

@Entity
public class Manager {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private String mid;
   
    @Column(length=20 ,nullable=false)
    private String name;
   
    @ManyToOne(fetch=FetchType.LAZY)
    private Department department;
   
    @Column(length=9 ,nullable=false)
    private String nic;
   
   
/*    @ManyToMany(cascade=CascadeType.ALL,fetch=FetchType.LAZY , mappedBy="managers")
    private Set emlpoyees;*/
   
    @OneToMany(fetch = FetchType.LAZY ,mappedBy = "manager_id")
    @JoinColumn(name = "manager_id", nullable = true)
    private Set em2;



    public String getNic() {
        return nic;
    }


    public void setNic(String nic) {
        this.nic = nic;
    }


    public String getName() {
        return name;
    }


    public void setName(String name) {
        this.name = name;
    }


   
    public Department getDepartment() {
        return department;
    }


    public void setDepartment(Department department) {
        this.department = department;
    }


    public String getMid() {
        return mid;
    }


    public void setMid(String mid) {
        this.mid = mid;
    }


    public Set getEm2() {
        return em2;
    }


    public void setEm2(Set em2) {
        this.em2 = em2;
    }


}
--------------------------------------------------------------
package com.company.entity;

import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.ManyToOne;

@Entity
public class EmployeeManager {
   
   
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private String id;
   
    @ManyToOne(fetch=FetchType.LAZY )
    private Employee employee_id ;
   
    @ManyToOne(fetch=FetchType.LAZY)
    private Manager manager_id ;
           
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public Employee getEmployee_id() {
        return employee_id;
    }
    public void setEmployee_id(Employee employee_id) {
        this.employee_id = employee_id;
    }
    public Manager getManager_id() {
        return manager_id;
    }
    public void setManager_id(Manager manager_id) {
        this.manager_id = manager_id;
    }
   
}

--------------------------------------------------

package com.emp.entity;

public class GenericEntity
{

    @Override
    public boolean equals(Object o)
    {
        if(o != null && o.getClass().equals(this.getClass()))
        {
            return true;
        }
        return false;
    }
   
      @Override
      public int hashCode()
      {
         int prime = 31;
        return prime *7/2;
      }
       
}


-------------------------------------------------------
package com.emp.entity;

import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;



public class MyEntityManager
{

    private javax.persistence.EntityManager em;
    private static final String PERSISTENT_UNIT ="myp";
   
    public MyEntityManager()
    {
       
        EntityManagerFactory factoty = Persistence.createEntityManagerFactory("myp");
        this.em = factoty.createEntityManager();
       
    }
   
    public javax.persistence.EntityManager getEm() {
        return em;
    }

   
}

--------------------------------------------------
CREATE TABLE sequence
(
  seq_name character varying(50) NOT NULL,
  seq_count numeric(38,0),
  CONSTRAINT sequence_pkey PRIMARY KEY (seq_name )
)
WITH (
  OIDS=FALSE
);
ALTER TABLE sequence
  OWNER TO postgres;




--"SEQ_GEN" 0



----------------DTO-----------------------

package com.emp.dto;

import java.util.Set;

import com.emp.entity.Department;
import com.emp.entity.EmployeeManager;

//Data transfer object for both direction(UI to entity /entity to UI)
public class EmployeeDto {

   
    private String empId;

    private String address;

    private String empName;

    private double salary;

    private Department department;

    private Set employeeManagers;
   
    public EmployeeDto() {
    }
   
    public EmployeeDto(String empId,String address,double salary,Department department,Set employeeManagers) {
       
        this.empId = empId;
        this.address = address;
        this.empName = address;
        this.salary = salary;
        this.department = department;
    }
   
    public EmployeeDto(com.emp.entity.Employee employee) {
       
        this.empId = employee.getEmpId();
        this.address = employee.getAddress();
        this.empName = employee.getEmpName();
        this.salary = employee.getSalary();
        this.department = employee.getDepartment();
        this.employeeManagers = employee.getEmployeeManagers();
    }

    public String getEmpId() {
        return empId;
    }

    public void setEmpId(String empId) {
        this.empId = empId;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getEmpName() {
        return empName;
    }

    public void setEmpName(String empName) {
        this.empName = empName;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }

    public Department getDepartment() {
        return department;
    }

    public void setDepartment(Department department) {
        this.department = department;
    }

    public Set getEmployeeManagers() {
        return employeeManagers;
    }

    public void setEmployeeManagers(Set employeeManagers) {
        this.employeeManagers = employeeManagers;
    }

   
}