001 /* 002 // $Id: //open/mondrian/src/main/mondrian/calc/HierarchyCalc.java#5 $ 003 // This software is subject to the terms of the Common Public License 004 // Agreement, available at the following URL: 005 // http://www.opensource.org/licenses/cpl.html. 006 // Copyright (C) 2006-2007 Julian Hyde 007 // All Rights Reserved. 008 // You must accept the terms of that agreement to use this software. 009 */ 010 package mondrian.calc; 011 012 import mondrian.olap.Evaluator; 013 import mondrian.olap.Hierarchy; 014 015 /** 016 * Expression which yields a {@link mondrian.olap.Hierarchy}. 017 * 018 * <p>When implementing this interface, it is convenient to extend 019 * {@link mondrian.calc.impl.AbstractHierarchyCalc}, but it is not required. 020 * 021 * @author jhyde 022 * @version $Id: //open/mondrian/src/main/mondrian/calc/HierarchyCalc.java#5 $ 023 * @since Sep 26, 2005 024 */ 025 public interface HierarchyCalc extends Calc { 026 /** 027 * Evaluates this expression to yield a hierarchy. 028 * 029 * <p>Never returns null. 030 * 031 * @param evaluator Evaluation context 032 * @return a hierarchy 033 */ 034 Hierarchy evaluateHierarchy(Evaluator evaluator); 035 } 036 037 // End HierarchyCalc.java