1 package org.apache.commons.jexl;
2
3 /***
4 * A Resolver allows custom resolution of the expression, and can be
5 * added in front of the jexl engine, or after in the evaluation
6 *
7 * @todo This needs to be explained in detail. Why do this?
8 * @author <a href="mailto:geirm@adeptra.com">Geir Magnusson Jr.</a>
9 * @version $Id: JexlExprResolver.java,v 1.3 2004/08/23 13:53:34 dion Exp $
10 */
11 public interface JexlExprResolver
12 {
13 Object NO_VALUE = new Object();
14
15 /***
16 * evaluates an expression against the context
17 *
18 * @todo Must detail the expectations and effects of this resolver.
19 * @param context current data context
20 * @param expression expression to evauluate
21 * @return value (may be null) po the NO_VALUE object to
22 * indicate no resolution.
23 */
24 Object evaluate(JexlContext context, String expression);
25 }