Java tutorial
// Copyright (C) 2016 The Android Open Source Project // // 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.gerrit.server.events; import static com.google.common.base.Preconditions.checkArgument; import com.google.common.base.Supplier; import com.google.common.base.Suppliers; import com.google.gson.JsonDeserializationContext; import com.google.gson.JsonDeserializer; import com.google.gson.JsonElement; import com.google.gson.JsonParseException; import java.lang.reflect.ParameterizedType; import java.lang.reflect.Type; public class SupplierDeserializer implements JsonDeserializer<Supplier<?>> { @Override public Supplier<?> deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException { checkArgument(typeOfT instanceof ParameterizedType); ParameterizedType parameterizedType = (ParameterizedType) typeOfT; if (parameterizedType.getActualTypeArguments().length != 1) { throw new JsonParseException("Expected one parameter type in Supplier interface."); } Type supplierOf = parameterizedType.getActualTypeArguments()[0]; return Suppliers.ofInstance(context.deserialize(json, supplierOf)); } }