Java tutorial
/* * This file is part of Sponge, licensed under the MIT License (MIT). * * Copyright (c) SpongePowered <https://www.spongepowered.org> * Copyright (c) contributors * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package co.aikar.util; import com.google.common.collect.Lists; import com.google.common.collect.Maps; import com.google.gson.Gson; import com.google.gson.GsonBuilder; import com.google.gson.JsonArray; import com.google.gson.JsonElement; import com.google.gson.JsonObject; import java.util.List; import java.util.Map; import java.util.Map.Entry; import java.util.function.Function; /** * Provides Utility methods that assist with generating JSON Objects */ public final class JSONUtil { static final Gson gson = new GsonBuilder().serializeNulls().create(); private JSONUtil() { } public static JsonArray arrayOf(Object... elements) { return gson.toJsonTree(elements).getAsJsonArray(); } public static JsonObjectBuilder objectBuilder() { return new JsonObjectBuilder(); } public static JsonObject singleObjectPair(String key, Object value) { return objectBuilder().add(key, value).build(); } public static JsonObject singleObjectPair(int key, Object value) { return objectBuilder().add(key, value).build(); } public static class JsonObjectBuilder { private final Map<String, Object> elements = Maps.newHashMap(); public JsonObjectBuilder add(int key, Object value) { return add(String.valueOf(key), value); } public JsonObjectBuilder add(String key, Object value) { if (value instanceof JsonObjectBuilder) { value = ((JsonObjectBuilder) value).build(); } this.elements.put(key, value); return this; } public JsonObject build() { return gson.toJsonTree(this.elements).getAsJsonObject(); } } public static <E> JsonArray mapArray(E[] elements, Function<E, Object> function) { return mapArray(Lists.newArrayList(elements), function); } public static <E> JsonArray mapArray(Iterable<E> elements, Function<E, Object> function) { List<Object> list = Lists.newArrayList(); for (E element : elements) { Object transformed = function.apply(element); if (transformed != null) { list.add(transformed); } } return gson.toJsonTree(list).getAsJsonArray(); } public static <E> JsonObject mapArrayToObject(E[] array, Function<E, JsonObject> function) { return mapArrayToObject(Lists.newArrayList(array), function); } public static <E> JsonObject mapArrayToObject(Iterable<E> iterable, Function<E, JsonObject> function) { JsonObjectBuilder builder = objectBuilder(); for (E element : iterable) { JsonObject obj = function.apply(element); if (obj == null) { continue; } for (Entry<String, JsonElement> entry : obj.entrySet()) { builder.add(entry.getKey(), entry.getValue()); } } return builder.build(); } public static String toString(JsonElement element) { return gson.toJson(element); } public static JsonElement toJsonElement(Object value) { return gson.toJsonTree(value); } }