valuefundef.java

来自「数据仓库展示程序」· Java 代码 · 共 69 行

/*
// $Id: //open/mondrian/src/main/mondrian/olap/fun/ValueFunDef.java#6 $
// This software is subject to the terms of the Common Public License
// Agreement, available at the following URL:
// http://www.opensource.org/licenses/cpl.html.
// (C) Copyright 2002-2005 Kana Software, Inc. and others.
// All Rights Reserved.
// You must accept the terms of that agreement to use this software.
//
// jhyde, Jun 14, 2002
*/

package mondrian.olap.fun;

import mondrian.olap.*;
import mondrian.olap.type.Type;

import java.io.PrintWriter;

/**
 * A <code>ValueFunDef</code> is a pseudo-function to evaluate a member or
 * a tuple. Similar to {@link TupleFunDef}.
 *
 * @author jhyde
 * @since Jun 14, 2002
 * @version $Id: //open/mondrian/src/main/mondrian/olap/fun/ValueFunDef.java#6 $
 **/
class ValueFunDef extends FunDefBase {
    private final int[] argTypes;

    ValueFunDef(int[] argTypes) {
        super(
            "_Value()",
            "_Value([<Member>, ...])",
            "Pseudo-function which evaluates a tuple.",
            Syntax.Parentheses,
            Category.Numeric,
            argTypes);
        this.argTypes = argTypes;
    }

    public int getReturnCategory() {
        return Category.Tuple;
    }

    public int[] getParameterTypes() {
        return argTypes;
    }

    public void unparse(Exp[] args, PrintWriter pw) {
        ExpBase.unparseList(pw, args, "(", ", ", ")");
    }

    public Type getResultType(Validator validator, Exp[] args) {
        return null;
    }

    public Object evaluate(Evaluator evaluator, Exp[] args) {
        Member[] members = new Member[args.length];
        for (int i = 0; i < args.length; i++) {
            members[i] = getMemberArg(evaluator, args, i, true);
        }
        Evaluator evaluator2 = evaluator.push(members);
        return evaluator2.evaluateCurrent();
    }
}

// End ValueFunDef.java