/*
* Copyright 2002-2015 the original author or authors.
*
* 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.
*/
import {SpelNode} from './SpelNode';
/**
* A function reference is of the form "#someFunction(a,b,c)". Functions may be defined in
* the context prior to the expression being evaluated or within the expression itself
* using a lambda function definition. For example: Lambda function definition in an
* expression: "(#max = {|x,y|$x>$y?$x:$y};max(2,3))" Calling context defined function:
* "#isEven(37)". Functions may also be static java methods, registered in the context
* prior to invocation of the expression.
*
* <p>Functions are very simplistic, the arguments are not part of the definition (right
* now), so the names must be unique.
*
* @author Andy Clement
* @author Ben March
* @since 0.2.0
*/
function createNode(parent, functionName) {
var node = SpelNode.create('method', parent);
node.getValue = function () {
var refNode = node,
context = null;
do {
if (refNode.getParent()) {
refNode = refNode.getParent();
} else {
context = refNode.getContext();
}
} while (refNode);
if (context[functionName]) {
return context[functionName].call(context);
}
throw {
name: 'FunctionDoesNotExistException',
message: 'Function \'' + functionName + '\' does not exist.'
};
};
return node;
}
export var FunctionReference = {
create: createNode
};
|