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/* * Copyright 2014 the original author or authors. * * 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.springframework.social.twitter.api.impl; import java.io.IOException; import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Locale; import java.util.regex.MatchResult; import java.util.regex.Matcher; import java.util.regex.Pattern; import org.springframework.social.twitter.api.*; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.databind.DeserializationContext; import com.fasterxml.jackson.databind.JsonDeserializer; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; /** * Custom Jackson deserializer for tweets. Tweets can't be simply mapped like other Twitter model objects because the JSON structure * varies between the search API and the timeline API. This deserializer determine which structure is in play and creates a tweet from it. * @author Craig Walls */ class TweetDeserializer extends JsonDeserializer<Tweet> { @Override public Tweet deserialize(final JsonParser jp, final DeserializationContext ctx) throws IOException { final JsonNode node = jp.readValueAs(JsonNode.class); if (null == node || node.isMissingNode() || node.isNull()) { return null; } final Tweet tweet = this.deserialize(node); jp.skipChildren(); return tweet; } public Tweet deserialize(JsonNode node) throws IOException, JsonProcessingException { final long id = node.path("id").asLong(); final String text = node.path("text").asText(); if (id <= 0 || text == null || text.isEmpty()) { return null; } JsonNode fromUserNode = node.get("user"); String dateFormat = TIMELINE_DATE_FORMAT; String fromScreenName = fromUserNode.get("screen_name").asText(); long fromId = fromUserNode.get("id").asLong(); String fromImageUrl = fromUserNode.get("profile_image_url").asText(); Date createdAt = toDate(node.get("created_at").asText(), new SimpleDateFormat(dateFormat, Locale.ENGLISH)); String source = node.get("source").asText(); JsonNode toUserIdNode = node.get("in_reply_to_user_id"); Long toUserId = toUserIdNode != null ? toUserIdNode.asLong() : null; String languageCode = node.get("lang").asText(); Tweet tweet = new Tweet(id, text, createdAt, fromScreenName, fromImageUrl, toUserId, fromId, languageCode, source); JsonNode inReplyToStatusIdNode = node.get("in_reply_to_status_id"); Long inReplyToStatusId = inReplyToStatusIdNode != null && !inReplyToStatusIdNode.isNull() ? inReplyToStatusIdNode.asLong() : null; tweet.setInReplyToStatusId(inReplyToStatusId); JsonNode inReplyToUserIdNode = node.get("in_reply_to_user_id"); Long inReplyUsersId = inReplyToUserIdNode != null && !inReplyToUserIdNode.isNull() ? inReplyToUserIdNode.asLong() : null; tweet.setInReplyToUserId(inReplyUsersId); tweet.setInReplyToScreenName(node.path("in_reply_to_screen_name").asText()); JsonNode retweetCountNode = node.get("retweet_count"); Integer retweetCount = retweetCountNode != null && !retweetCountNode.isNull() ? retweetCountNode.asInt() : null; tweet.setRetweetCount(retweetCount); JsonNode retweetedNode = node.get("retweeted"); JsonNode retweetedStatusNode = node.get("retweeted_status"); boolean retweeted = retweetedNode != null && !retweetedNode.isNull() ? retweetedNode.asBoolean() : false; tweet.setRetweeted(retweeted); Tweet retweetedStatus = retweetedStatusNode != null ? this.deserialize(retweetedStatusNode) : null; tweet.setRetweetedStatus(retweetedStatus); JsonNode favoritedNode = node.get("favorited"); boolean favorited = favoritedNode != null && !favoritedNode.isNull() ? favoritedNode.asBoolean() : false; tweet.setFavorited(favorited); JsonNode favoriteCountNode = node.get("favorite_count"); Integer favoriteCount = favoriteCountNode != null && !favoriteCountNode.isNull() ? favoriteCountNode.asInt() : null; tweet.setFavoriteCount(favoriteCount); Entities entities = toEntities(node.get("entities"), text); tweet.setEntities(entities); TwitterProfile user = toProfile(fromUserNode); tweet.setUser(user); JsonNode coordinatesNode = node.get("coordinates"); Coordinates coordinates = toCoordinates(coordinatesNode); tweet.setCoordinates(coordinates); JsonNode placeNode = node.get("place"); Place place = toPlace(placeNode); tweet.setPlace(place); return tweet; } private ObjectMapper createMapper() { final ObjectMapper mapper = new ObjectMapper(); mapper.registerModule(new TwitterModule()); return mapper; } private Date toDate(String dateString, DateFormat dateFormat) { if (dateString == null) { return null; } try { return dateFormat.parse(dateString); } catch (ParseException e) { return null; } } // passing in text to fetch ticker symbol pseudo-entities private Entities toEntities(final JsonNode node, String text) throws IOException { if (null == node || node.isNull() || node.isMissingNode()) { return null; } final ObjectMapper mapper = this.createMapper(); Entities entities = mapper.reader(Entities.class).readValue(node); extractTickerSymbolEntitiesFromText(text, entities); return entities; } private void extractTickerSymbolEntitiesFromText(String text, Entities entities) { Pattern pattern = Pattern.compile("\\$[A-Za-z]+"); Matcher matcher = pattern.matcher(text); while (matcher.find()) { MatchResult matchResult = matcher.toMatchResult(); String tickerSymbol = matchResult.group().substring(1); String url = "https://twitter.com/search?q=%24" + tickerSymbol + "&src=ctag"; entities.getTickerSymbols().add(new TickerSymbolEntity(tickerSymbol, url, new int[] { matchResult.start(), matchResult.end() })); } } private TwitterProfile toProfile(final JsonNode node) throws IOException { if (null == node || node.isNull() || node.isMissingNode()) { return null; } final ObjectMapper mapper = this.createMapper(); return mapper.reader(TwitterProfile.class).readValue(node); } private Coordinates toCoordinates(final JsonNode node) throws IOException { if (null == node || node.isNull() || node.isMissingNode()) { return null; } final ObjectMapper mapper = this.createMapper(); return mapper.reader(Coordinates.class).readValue(node); } private Place toPlace(final JsonNode node) throws IOException { if (null == node || node.isNull() || node.isMissingNode()) { return null; } final ObjectMapper mapper = this.createMapper(); return mapper.reader(Place.class).readValue(node); } private static final String TIMELINE_DATE_FORMAT = "EEE MMM dd HH:mm:ss ZZZZZ yyyy"; }