com.codename1.processing.Evaluator Maven / Gradle / Ivy
/*
* Copyright (c) 2012, Eric Coolman, Codename One and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Codename One designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Codename One through http://www.codenameone.com/ if you
* need additional information or have any questions.
*/
package com.codename1.processing;
import java.util.List;
/**
* Private interface, do not use.
*
* Predicate Evaluator interface, for handling predicate expressions (those within square backets
* of the path). Example:
*
* Example predicates:
*
*
* Test price attribute:
*
* [@price > 45]
*
* Test Child node:
*
* [town='Exeter']
*
* Test attribute exists
*
* [@price]
*
* Test attribute doesn't exist:
*
* [@price = null]
*
* Select by index:
*
* [3]
*
* Select by position:
*
* [position() < 5]
*
* Select by position:
*
* [last() - 5]
*
*
*
* @author Eric Coolman
*
*/
interface Evaluator {
/**
* Evaluate a predicate expression against an array of StructuredContent elements. This method
* should return an array of elements that matched the given predicate expression. If only a
* single match is found, a single StructuredContent element may be returned (not required).
*
* @param elements an array of StructuredContent elements.
* @return Either a single StructuredContent element, or an array of StructuredContent elements.
* @throws IllegalArgumentException thrown if there is an error processing the predicate expression.
*/
public Object evaluate(List elements)
throws IllegalArgumentException;
/**
* Evaluate a predicate expression against a single StructuredContent elements. This method
* should return an array of elements that matched the given predicate expression. If only a
* single match is found, a single StructuredContent element may be returned (not required).
* NOTE: Normally this method would return a single element, but an array could be produced
* if the predicate uses globbing.
*
* @param elements a single StructuredContent element.
* @return Either a single StructuredContent element, or an array of StructuredContent elements.
* @throws IllegalArgumentException thrown if there is an error processing the predicate expression.
*/
public Object evaluate(StructuredContent element)
throws IllegalArgumentException;
}