001/*
002 * ModeShape (http://www.modeshape.org)
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *       http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.modeshape.jdbc.rest;
017
018import java.util.ArrayList;
019import java.util.Collections;
020import java.util.List;
021import org.codehaus.jettison.json.JSONArray;
022import org.codehaus.jettison.json.JSONException;
023import org.codehaus.jettison.json.JSONObject;
024
025/**
026 * Helper class used by the client to parse {@link org.codehaus.jettison.json.JSONObject}
027 *
028 * @author Horia Chiorean (hchiorea@redhat.com)
029 */
030public final class JSONHelper {
031
032    private JSONHelper() {
033    }
034
035    protected static List<String> valuesFrom( JSONObject json,
036                                           String name ) {
037        if (!json.has(name)) {
038            // Just an empty collection ...
039            return Collections.emptyList();
040        }
041        Object prop = null;
042        try {
043            prop = json.get(name);
044            if (prop instanceof JSONArray) {
045                // There are multiple values ...
046                JSONArray array = (JSONArray)prop;
047                int length = array.length();
048                if (length == 0) {
049                    return Collections.emptyList();
050                }
051                List<String> result = new ArrayList<>(length);
052                for (int i = 0; i < length; i++) {
053                    String value = array.getString(i);
054                    result.add(value);
055                }
056                return result;
057            }
058        } catch (JSONException e) {
059            throw new RuntimeException(e);
060        }
061        // Just a single value ...
062        return Collections.singletonList(prop.toString());
063    }
064
065    protected static boolean valueFrom( JSONObject object,
066                                     String name,
067                                     boolean defaultValue ) {
068        if (!object.has(name)) {
069            return defaultValue;
070        }
071        try {
072            return object.getBoolean(name);
073        } catch (JSONException e) {
074            throw new RuntimeException(e);
075        }
076    }
077
078    protected static String valueFrom( JSONObject object,
079                                    String name ) {
080        return valueFrom(object, name, null);
081    }
082
083    protected static String valueFrom( JSONObject object,
084                                    String name,
085                                    String defaultValue ) {
086        if (!object.has(name)) {
087            return defaultValue;
088        }
089        try {
090            return object.getString(name);
091        } catch (JSONException e) {
092            throw new RuntimeException(e);
093        }
094    }
095}