com.google.iosched.model.DataModelHelper.java Source code

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Here is the source code for com.google.iosched.model.DataModelHelper.java

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/*
 * Copyright 2014 Google Inc. All rights reserved.
 *
 * 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.google.iosched.model;

import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonPrimitive;
import com.google.iosched.model.validator.Converter;
import com.google.iosched.model.validator.ConverterException;

/**
 * Helper class with methods to help JSON data model handling.
 *
 */
public class DataModelHelper {

    /**
     * Hardcoded category of a tag to be considered for hashtag.
     */
    static final String CATEGORY_FOR_HASHTAG = "TOPIC";

    public static void set(JsonObject source, Enum<?> sourceProperty, JsonObject dest, Enum<?> destProperty) {
        set(source, sourceProperty, dest, destProperty, null);
    }

    public static void set(JsonObject source, Enum<?> sourceProperty, JsonObject dest, Enum<?> destProperty,
            Converter sourceConverter) {
        set(get(source, sourceProperty, sourceConverter), dest, destProperty);
    }

    public static void set(JsonElement value, JsonObject dest, Enum<?> destProperty) {
        if (value != null && dest != null) {
            dest.add(maybeFixPropertyName(destProperty.name()), value);
        }
    }

    public static JsonArray getAsArray(JsonObject source, Enum<?> sourceProperty) {
        if (source == null) {
            return null;
        }
        JsonElement el = source.get(sourceProperty.name());
        if (el == null || !el.isJsonArray()) {
            return null;
        }
        return el.getAsJsonArray();
    }

    @SuppressWarnings("rawtypes")
    public static JsonElement get(JsonObject source, Enum sourceProperty) {
        return get(source, sourceProperty, null);
    }

    @SuppressWarnings("rawtypes")
    public static JsonElement get(JsonObject source, Enum sourceProperty, Converter sourceConverter) {
        JsonElement value = source.get(maybeFixPropertyName(sourceProperty.name()));
        if (sourceConverter != null) {
            value = sourceConverter.convert(value);
        }
        return value;
    }

    public static JsonPrimitive getMapValue(JsonElement map, String key, Converter converter,
            String defaultValueStr) {
        JsonPrimitive defaultValue = null;
        if (defaultValueStr != null) {
            defaultValue = new JsonPrimitive(defaultValueStr);
            if (converter != null)
                defaultValue = converter.convert(defaultValue);
        }
        if (map == null || !map.isJsonArray()) {
            return defaultValue;
        }
        for (JsonElement el : map.getAsJsonArray()) {
            if (!el.isJsonObject()) {
                continue;
            }
            JsonObject obj = el.getAsJsonObject();
            if (!obj.has("name") || !obj.has("value")) {
                continue;
            }
            if (key.equals(obj.getAsJsonPrimitive("name").getAsString())) {
                JsonElement value = obj.get("value");
                if (!value.isJsonPrimitive()) {
                    throw new ConverterException(value, converter, "Expected a JsonPrimitive");
                }
                if (converter != null)
                    value = converter.convert(value);
                return value.getAsJsonPrimitive();
            }
        }
        return defaultValue;
    }

    public static String maybeFixPropertyName(String name) {
        if (name.charAt(0) == '_') {
            return name.substring(1);
        } else {
            return name;
        }
    }

    static boolean isHashtag(JsonObject tag) {
        return CATEGORY_FOR_HASHTAG.equals(get(tag, OutputJsonKeys.Tags.category).getAsString());
    }
}