package auction.persistence;import org.hibernate.*;import org.hibernate.usertype.UserType;import auction.model.*;import java.math.BigDecimal;import java.sql.*;import java.util.Currency;import java.io.Serializable;/** * This is a simple Hibernate custom mapping type for MonetaryAmount value types. * <p> * Note that this mapping type is for legacy databases that only have a * single numeric column to hold monetary amounts. Every <tt>MonetaryAmount</tt> * will be converted to USD (using some conversion magic of the class itself) * and saved to the database. * <p> * Do not ask me how this currency conversion works. It doesn't work, it's not implemented. * The whole point of this class is not to show how you can convert money, but how * you can write a custom UserType. *  * @author Christian Bauer */public class MonetaryAmountSimpleUserType		implements UserType {	public int[] sqlTypes() {        return new int[]{ Hibernate.BIG_DECIMAL.sqlType() };    }	public Class returnedClass() { return MonetaryAmount.class; }	public boolean isMutable() { return false; }	public Object deepCopy(Object value) {		return value;	}    public Serializable disassemble(Object value) {        return (Serializable) value;    }    public Object assemble(Serializable cached, Object owner) {        return cached;    }    public Object replace(Object original, Object target, Object owner) {        return original;    }    public boolean equals(Object x, Object y) {        if (x == y) return true;        if (x == null || y == null) return false;        return x.equals(y);    }    public int hashCode(Object x) {        return x.hashCode();    }	public Object nullSafeGet(ResultSet resultSet,							  String[] names,							  Object owner)			throws HibernateException, SQLException {		BigDecimal valueInUSD = resultSet.getBigDecimal(names[0]);        if (resultSet.wasNull()) return null; // Has to be done after first read		Currency storedCurrency = Currency.getInstance("USD");		return new MonetaryAmount(valueInUSD, storedCurrency);	}	public void nullSafeSet(PreparedStatement statement,							Object value,							int index)			throws HibernateException, SQLException {		if (value == null) {			statement.setNull(index, Hibernate.BIG_DECIMAL.sqlType());		} else {			MonetaryAmount anyCurrency = (MonetaryAmount)value;			MonetaryAmount amountInUSD =			  MonetaryAmount.convert( anyCurrency,									  Currency.getInstance("USD") );			statement.setBigDecimal(index, amountInUSD.getValue());		}	}}