Java tutorial
/* * Copyright 2013 Agorava * * 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 org.agorava.facebook.jackson; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.DeserializationContext; import com.fasterxml.jackson.databind.JsonDeserializer; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; import org.agorava.facebook.model.Comment; import org.agorava.facebook.model.ListAndCount; import java.io.IOException; import java.util.Collections; import java.util.List; import static org.agorava.api.atinject.BeanResolver.getInstance; class CommentListAndCountDeserializer extends JsonDeserializer<ListAndCount<Comment>> { @SuppressWarnings("unchecked") @Override public ListAndCount<Comment> deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JsonProcessingException { ObjectMapper mapper = getInstance().resolve(ObjectMapper.class); jp.setCodec(mapper); if (jp.hasCurrentToken()) { JsonNode commentsNode = jp.readValueAs(JsonNode.class); JsonNode dataNode = commentsNode.get("data"); List<Comment> commentsList = dataNode != null ? (List<Comment>) mapper.reader(new TypeReference<List<Comment>>() { }).readValue(dataNode) : Collections.<Comment>emptyList(); return new ListAndCount<Comment>(commentsList, commentsList.size()); } return null; } }