001/*
002 * The contents of this file are subject to the terms of the Common Development and
003 * Distribution License (the License). You may not use this file except in compliance with the
004 * License.
005 *
006 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
007 * specific language governing permission and limitations under the License.
008 *
009 * When distributing Covered Software, include this CDDL Header Notice in each file and include
010 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
011 * Header, with the fields enclosed by brackets [] replaced by your own identifying
012 * information: "Portions copyright [year] [name of copyright owner]".
013 *
014 * Copyright 2015 ForgeRock AS.
015 */
016package org.forgerock.openig.el;
017
018import java.util.ArrayList;
019import java.util.LinkedHashMap;
020import java.util.List;
021import java.util.Map;
022
023
024/**
025 * Utility class for evaluating expression in some collections.
026 */
027public final class Expressions {
028
029    private Expressions() {
030        // Prevent from instantiating.
031    }
032
033    /**
034     * Evaluate a map that may contain some values that needs to be evaluated.
035     *
036     * @param map the map to evaluate
037     * @param bindings the bindings used for the evaluation
038     * @return a new Map containing the result of the evaluation.
039     * @throws ExpressionException if an error occurs while evaluating the expression
040     */
041    public static Map<String, Object> evaluate(Map<String, Object> map, Bindings bindings) throws ExpressionException {
042        Map<String, Object> result = new LinkedHashMap<>(map.size());
043        for (Map.Entry<String, Object> entry : map.entrySet()) {
044            result.put(entry.getKey(), evaluate(entry.getValue(), bindings));
045        }
046        return result;
047    }
048
049    /**
050     * Evaluate a list that may contain some String that needs to be evaluated.
051     *
052     * @param list the list to evaluate
053     * @param bindings the bindings used for the evaluation
054     * @return a new list containing the results of the evaluations
055     * @throws ExpressionException if an error occurs while evaluating the expression
056     */
057    public static List<Object> evaluate(List<Object> list, Bindings bindings) throws ExpressionException {
058        List<Object> evaluatedList = new ArrayList<>();
059        for (Object object : list) {
060            evaluatedList.add(evaluate(object, bindings));
061        }
062        return evaluatedList;
063    }
064
065    /**
066     * Evaluate a String.
067     *
068     * @param value the String to evaluate
069     * @param bindings the bindings used for the evaluation
070     * @return the result of the evaluation.
071     * @throws ExpressionException if an error occurs while evaluating the expression
072     */
073    public static Object evaluate(String value, Bindings bindings) throws ExpressionException {
074        return Expression.valueOf(value, Object.class).eval(bindings);
075    }
076
077    /**
078     * Evaluate an Object that may contain some String that needs to be evaluated. The supported types of Object are :
079     * String, List and Map.
080     *
081     * @param value the String to evaluate
082     * @param bindings the bindings used for the evaluation
083     * @return the result of the evaluation.
084     * @throws ExpressionException if an error occurs while evaluating the expression
085     */
086    @SuppressWarnings("unchecked")
087    public static Object evaluate(Object value, Bindings bindings) throws ExpressionException {
088        if (value instanceof String) {
089            return evaluate((String) value, bindings);
090        } else if (value instanceof List) {
091            return evaluate((List) value, bindings);
092        } else if (value instanceof Map) {
093            return evaluate((Map) value, bindings);
094        } else {
095            return value;
096        }
097    }
098}