/*
* Copyright 2016 Nabarun Mondal
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package com.noga.njexl.lang;
/**
* Represents a single JEXL expression.
* <p>
* This simple interface provides access to the underlying expression through
* {@link Expression#getExpression()}.
* </p>
*
* <p>
* An expression is different than a script - it is simply a reference of
* an expression.
* </p>
*
* @since 1.0
*/
public interface Expression {
/**
* Evaluates the expression with the variables contained in the
* supplied {@link JexlContext}.
*
* @param context A JexlContext containing variables.
* @return The result of this evaluation
* @throws JexlException on any error
*/
Object evaluate(JexlContext context);
/**
* Returns the JEXL expression this Expression was created with.
*
* @return The JEXL expression to be evaluated
*/
String getExpression();
/**
* Returns the JEXL expression by reconstructing it from the parsed tree.
* @return the JEXL expression
*/
String dump();
}