Line data    Source code

       1             : // Copyright (C) 2014 The Android Open Source Project
       2             : //
       3             : // Licensed under the Apache License, Version 2.0 (the "License");
       4             : // you may not use this file except in compliance with the License.
       5             : // You may obtain a copy of the License at
       6             : //
       7             : // http://www.apache.org/licenses/LICENSE-2.0
       8             : //
       9             : // Unless required by applicable law or agreed to in writing, software
      10             : // distributed under the License is distributed on an "AS IS" BASIS,
      11             : // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      12             : // See the License for the specific language governing permissions and
      13             : // limitations under the License.
      14             : 
      15             : package com.google.gerrit.server.events;
      16             : 
      17             : import com.google.gson.JsonDeserializationContext;
      18             : import com.google.gson.JsonDeserializer;
      19             : import com.google.gson.JsonElement;
      20             : import com.google.gson.JsonParseException;
      21             : import java.lang.reflect.Type;
      22             : 
      23             : /**
      24             :  * JSON deserializer for {@link Event}s.
      25             :  *
      26             :  * <p>Deserialized objects are of an appropriate subclass based on the value of the top-level "type"
      27             :  * element.
      28             :  */
      29           2 : public class EventDeserializer implements JsonDeserializer<Event> {
      30             :   @Override
      31             :   public Event deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
      32             :       throws JsonParseException {
      33           0 :     if (!json.isJsonObject()) {
      34           0 :       throw new JsonParseException("Not an object");
      35             :     }
      36           0 :     JsonElement typeJson = json.getAsJsonObject().get("type");
      37           0 :     if (typeJson == null
      38           0 :         || !typeJson.isJsonPrimitive()
      39           0 :         || !typeJson.getAsJsonPrimitive().isString()) {
      40           0 :       throw new JsonParseException("Type is not a string: " + typeJson);
      41             :     }
      42           0 :     String type = typeJson.getAsJsonPrimitive().getAsString();
      43           0 :     Class<?> cls = EventTypes.getClass(type);
      44           0 :     if (cls == null) {
      45           0 :       throw new JsonParseException("Unknown event type: " + type);
      46             :     }
      47           0 :     return context.deserialize(json, cls);
      48             :   }
      49             : }