Java Tutorial/JPA/Join Column

Column Definition For Join Column

File: Employee.java

   <source lang="java">

import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.ManyToOne; @Entity public class Employee {

   @Id
   int id;
   
   @ManyToOne 
   @JoinColumn(name="MGR", columnDefinition="VARCHAR(40)")
   private Employee manager;
   

}</source>

Nullable Join Column

File: Address.java

   <source lang="java">

import javax.persistence.Entity; import javax.persistence.Id; @Entity public class Address {

   @Id
   private int id;
   private String street;
   private String city;
   private String state;
   private String zip;
   
   public int getId() {
       return id;
   }
   
   public void setId(int id) {
       this.id = id;
   }
   
   public String getStreet() {
       return street;
   }
   
   public void setStreet(String address) {
       this.street = address;
   }
   public String getCity() {
       return city;
   }
   public void setCity(String city) {
       this.city = city;
   }
   public String getState() {
       return state;
   }
   public void setState(String state) {
       this.state = state;
   }
   public String getZip() {
       return zip;
   }
   public void setZip(String zip) {
       this.zip = zip;
   }
   public String toString() {
       return "Address id: " + getId() + 
              ", street: " + getStreet() +
              ", city: " + getCity() +
              ", state: " + getState() +
              ", zip: " + getZip();
   }

}</source>