package ejava.examples.orm.core;
   
   import java.io.Serializable;
   
   /**
    * This is an example of a class that can be used for a Java Persistence
    * IdClass. Its requirements are that it have a default ctor() and it 
    * correctly override hashCode() and equals(). Not annotations or orm.xml
    * mappings are required for this specific class. All annotations and orm.xml 
   * entries are supplied by the classes this PK class identifies.
   */
  public class MowerPK implements Serializable {
      private static final long serialVersionUID = 1L;
      private String make;
      private String model;
      
      public MowerPK() {}
      public MowerPK(String make, String model) {
          this.make = make;
          this.model = model;
      }
  
      public String getMake() { return make; }
      public String getModel() { return model; }
      
      @Override
      public int hashCode() { return make.hashCode() + model.hashCode(); }
      @Override
      public boolean equals(Object obj) {
          try {
              if (this == obj) return true;
              return make.equals(((MowerPK)obj).getMake()) &&
                     model.equals(((MowerPK)obj).getModel());
              
          } catch (Throwable ignored) { //catch NP & Cast Exceptions 
              return false;
          }
      }
      
      @Override
      public String toString() {
          return super.toString() +
              ", make=" + make +
              ", model=" + model;
      }
  }