@Entity
@Table(name = "customer")

public class Customer implements java.io.Serializable {

   /** The Constant serialVersionUID. */
   private static final long serialVersionUID = -6910750598751114269L;

   /** The person nr. */
   private String customerId;

   /** The kreditkarten. */
   private Set<CustomerAccount> accounts= new HashSet<CustomerAccount>(0);

   /**
    * Instantiates a new Customer .
    */
   public Customer () {
   }

   public void setAccount(Set<CustomerAccount> accounts) {
      this.accounts = accounts;
   }

   @OneToMany(mappedBy = "customer")
   public Set<CustomerAccount> getAccounts() {
      return accounts;
   }

}

/**
* KontoKunde generated by hbm2java.
*/
@Entity
@Table(name = "customer_account")
public class CustomerAccount implements java.io.Serializable {
   
   @Embeddable
   public static class Id implements java.io.Serializable {

      /** The Constant serialVersionUID. */
      private static final long serialVersionUID = -4670709908869684158L;
      
      /** The person nr. */
      private String customerNo;
      
      /** The konto nr. */
      private String accountNo;

      /**
       * Instantiates a new konto kunde id.
       */
      public Id() {
      }

      /** Getter and Setter for Id */
   }

   /** The Constant serialVersionUID. */
   private static final long serialVersionUID = 5462194076796527642L;

   /** The id. */
   private Id id = new Id();

   /** The kunde. */
   private Customer customer;

   /** The konto. */
   private Account account;

   /**
    * Instantiates a new konto kunde.
    */
   public CustomerAccount() {
   }

   
   /*
    * Instantiates a new konto kunde.
    *
    * @param id
    *            the id
    * @param kontoart
    *            the kontoart
    */
   
   /**
    * Erzeugt neue Kunden-Konto Verknuepfung.
    *
    * @param kunde Kunde
    * @param konto Konto
    * @param kontoart Art des Kontos (E Einzel, G Gemeinschaft)
    */
   public CustomerAccount(Customer cust, Account acc) {
      this.id.customerNo = customer.getCustomerNr();
      this.id.accountNo = account.getAccountNo();
            
      customer = cust;
                account = acc;
   }

   /**
    * Gets the id.
    *
    * @return the id
    */
   @EmbeddedId
   @AttributeOverrides( {
         @AttributeOverride(name = "customerNo", column = @Column(name = "customer_no", nullable = false)),
         @AttributeOverride(name = "accountNo", column = @Column(name = "account_no", nullable = false)) })
   public Id getId() {
      return this.id;
   }

   /**
    * Sets the id.
    *
    * @param id
    *            the new id
    */
   public void setId(Id id) {
      this.id = id;
   }

   /**
    * Gets the kunde.
    *
    * @return the kunde
    */
   @ManyToOne(fetch = FetchType.LAZY)
   @JoinColumn(name = "customer_no", nullable = false, insertable = false, updatable = false)
   @org.hibernate.validator.NotNull
   public Kunde getCustomer() {
      return this.customer;
   }

   /**
    * Sets the kunde.
    *
    * @param kunde
    *            the new kunde
    */
   public void setCustomer(Customer cust) {
      this.customer = cust;
      this.id.customerNo = cust.getCustomerNo();
   }

   /**
    * Gets the konto.
    *
    * @return the konto
    */
   @ManyToOne(fetch = FetchType.LAZY)
   @JoinColumn(name = "account_no", nullable = false, insertable = false, updatable = false)
   @org.hibernate.annotations.ForeignKey(name = "fk_kunde_konto_konto_nr")
   public Konto getAccount() {
      return this.account;
   }

   /**
    * Sets the konto.
    *
    * @param konto
    *            the new konto
    */
   public void setAccount(Account acc) {
      this.account= acc;
      this.id.accountNo = acc.getAccountNo();
   }
}

/**
* Konto.
*/
@Entity
@Table(name = "account")
public class Account implements java.io.Serializable {

   /** The Constant serialVersionUID. */
   private static final long serialVersionUID = 3825508146221476748L;

   /** The konto nr. */
   private String accountNo;

   /** Kunden. */
   private Set<CustomerAccount> customer = new HashSet<CustomerAccount>(0);

   /**
    * Instantiates a new konto.
    */
   public Konto() {
   }

   /**
    * Gets the konto nr.
    *
    * @return the konto nr
    */
   @Id
   @Column(name = "account_no", unique = true, nullable = false, length = 10)
   @org.hibernate.validator.NotNull
   @org.hibernate.validator.Pattern(regex = "[0-9]{6,10}+")
   public String getAccountNo() {
      return this.accountNo;
   }

   /**
    * Sets the konto nr.
    *
    * @param kontoNr
    *            the new konto nr
    */
   public void setAccountNo(String accountNo) {
      this.accountNo = accountNo;
   }

   public void setCustomer(Set<CustomerAccount> cust) {
      customer = cust;
   }

   @OneToMany(mappedBy = "account")
   public Set<CustomerAccount> getCustomer() {
      return customer;
   }
}

   public Customer findById(String customerNo) {
      return em.find(Customer, customerNo);
   }

/* load de.hd.persistence.Customer */ select
        customer0_.customer_no as customer1_595_0_,
        ...
    from
        customer customer0_
    where
        customer0_.customer_nr=?
15:44:21,234 INFO  [STDOUT] Hibernate:
    /* load one-to-many de.hd.persistence.Customer.accounts */ select
        accounts0_.customer_no as customer2_1_,
        accounts0_.account_no as account1_1_,
        accounts0_.account_no as account1_607_0_,
        accounts0_.customer_no as customer2_607_0_
    from
        customer_account account0_
    where
        account0_.customer_no=?