package ejava.examples.orm.core.mapped;
   
   import java.io.Serializable;
   
   import javax.persistence.*;
   
   /**
    * This class provides an example of a primary key class that can be 
    * embedded into the referenced class. The containing class will simply
   * use an instance of this class rather than having separate fields that
   * match the fields of this class. All fields will be mapped by the 
   * containing class.
   */
  @Embeddable
  public class MakeModelPK implements Serializable {
      private static final long serialVersionUID = 1L;
      private String make;
      private String model;
      
      public MakeModelPK() {}
      public MakeModelPK(String make, String model) {
          this.make = make;
          this.model = model;
      }
      
      public String getMake() { return make; }
      public String getModel() { return model; }
  
      public int hashCode() { return make.hashCode() + model.hashCode(); }
      public boolean equals(Object obj) {
          try {
              if (this == obj) return true;
              return make.equals(((MakeModelPK)obj).getMake()) &&
                     model.equals(((MakeModelPK)obj).getModel());
              
          } catch (Throwable ignored) { //catch NP & Cast Exceptions 
              return false;
          }
      }
      
      public String toString() {
          return super.toString() +
              ", make=" + make +
              ", model=" + model;
      }
  }