BaseEntity.java

package petclinic.util;

import java.io.*;
import javax.persistence.*;

/**
 * Base class for all entity types, containing the id property, which is automatically generated.
 */
@MappedSuperclass
public class BaseEntity implements Serializable
{
   @Id
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   protected Integer id;

   public Integer getId() { return id; }
   public void setId(Integer id) { this.id = id; }

   public boolean isNew() { return id == null; }

   @SuppressWarnings("NonFinalFieldReferenceInEquals")
   @Override
   public final boolean equals(Object other)
   {
      if (this == other) return true;
      if (!(other instanceof BaseEntity)) return false;

      BaseEntity otherEntity = (BaseEntity) other;

      return id != null ? id.equals(otherEntity.id) : otherEntity.id == null;
   }

   @SuppressWarnings("NonFinalFieldReferencedInHashCode")
   @Override
   public final int hashCode()
   {
      return id == null ? 0 : id.hashCode();
   }
}