org.hibernate.internal.util.collections.ArrayHelper#slice ( )源码实例Demo

@Override
protected Object[] getResultRow(Object[] row, ResultSet rs, SharedSessionContractImplementor session)
		throws SQLException, HibernateException {
	final Object[] result;
	if ( translator.hasProjection() ) {
		Type[] types = translator.getProjectedTypes();
		result = new Object[types.length];
		String[] columnAliases = translator.getProjectedColumnAliases();
		for ( int i=0, pos=0; i<result.length; i++ ) {
			int numColumns = types[i].getColumnSpan( session.getFactory() );
			if ( numColumns > 1 ) {
				String[] typeColumnAliases = ArrayHelper.slice( columnAliases, pos, numColumns );
				result[i] = types[i].nullSafeGet(rs, typeColumnAliases, session, null);
			}
			else {
				result[i] = types[i].nullSafeGet(rs, columnAliases[pos], session, null);
			}
			pos += numColumns;
		}
	}
	else {
		result = toResultRow( row );
	}
	return result;
}
 

/**
 * Get the qualified (prefixed by alias) names of the columns of the owning entity which are to be used in the join
 *
 * @param associationType The association type for the association that represents the join
 * @param columnQualifier The left-hand side table alias
 * @param propertyIndex The index of the property that represents the association/join
 * @param begin The index for any nested (composites) attributes
 * @param lhsPersister The persister for the left-hand side of the association/join
 * @param mapping The mapping (typically the SessionFactory).
 *
 * @return The qualified column names.
 */
public static String[] getAliasedLHSColumnNames(
		AssociationType associationType,
		String columnQualifier,
		int propertyIndex,
		int begin,
		OuterJoinLoadable lhsPersister,
		Mapping mapping) {
	if ( associationType.useLHSPrimaryKey() ) {
		return StringHelper.qualify( columnQualifier, lhsPersister.getIdentifierColumnNames() );
	}
	else {
		final String propertyName = associationType.getLHSPropertyName();
		if ( propertyName == null ) {
			return ArrayHelper.slice(
					toColumns( lhsPersister, columnQualifier, propertyIndex ),
					begin,
					associationType.getColumnSpan( mapping )
			);
		}
		else {
			//bad cast
			return ( (PropertyMapping) lhsPersister ).toColumns( columnQualifier, propertyName );
		}
	}
}
 

/**
 * Get the columns of the owning entity which are to be used in the join
 *
 * @param type The type representing the join
 * @param property The property index for the association type
 * @param begin ?
 * @param lhsPersister The persister for the left-hand-side of the join
 * @param mapping The mapping object (typically the SessionFactory)
 *
 * @return The columns for the left-hand-side of the join
 */
public static String[] getLHSColumnNames(
		AssociationType type,
		int property,
		int begin,
		OuterJoinLoadable lhsPersister,
		Mapping mapping) {
	if ( type.useLHSPrimaryKey() ) {
		//return lhsPersister.getSubclassPropertyColumnNames(property);
		return lhsPersister.getIdentifierColumnNames();
	}
	else {
		final String propertyName = type.getLHSPropertyName();
		if ( propertyName == null ) {
			//slice, to get the columns for this component
			//property
			return ArrayHelper.slice(
					property < 0
							? lhsPersister.getIdentifierColumnNames()
							: lhsPersister.getSubclassPropertyColumnNames( property ),
					begin,
					type.getColumnSpan( mapping )
			);
		}
		else {
			//property-refs for associations defined on a
			//component are not supported, so no need to slice
			return lhsPersister.getPropertyColumnNames( propertyName );
		}
	}
}
 

@Override
public Object hydrate(
		final ResultSet rs,
		final String[] names,
		final SharedSessionContractImplementor session,
		final Object owner)
		throws HibernateException, SQLException {

	int begin = 0;
	boolean notNull = false;
	Object[] values = new Object[propertySpan];
	for ( int i = 0; i < propertySpan; i++ ) {
		int length = propertyTypes[i].getColumnSpan( session.getFactory() );
		String[] range = ArrayHelper.slice( names, begin, length ); //cache this
		Object val = propertyTypes[i].hydrate( rs, range, session, owner );
		if ( val == null ) {
			if ( isKey ) {
				return null; //different nullability rules for pk/fk
			}
		}
		else {
			notNull = true;
		}
		values[i] = val;
		begin += length;
	}

	return notNull ? values : null;
}