/* * Copyright 2015 Anton Tananaev (anton.tananaev@gmail.com) * * 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.traccar.geocode; import com.ning.http.client.AsyncCompletionHandler; import com.ning.http.client.Response; import java.util.AbstractMap; import java.util.Collections; import java.util.LinkedHashMap; import java.util.Map; import javax.json.Json; import javax.json.JsonObject; import javax.json.JsonReader; import org.traccar.Context; public abstract class JsonReverseGeocoder implements ReverseGeocoder { private final String url; private Map<Map.Entry<Double, Double>, String> cache; public JsonReverseGeocoder(String url, final int cacheSize) { this.url = url; if (cacheSize > 0) { this.cache = Collections.synchronizedMap(new LinkedHashMap<Map.Entry<Double, Double>, String>() { @Override protected boolean removeEldestEntry(Map.Entry eldest) { return size() > cacheSize; } }); } } @Override public void getAddress( final AddressFormat format, final double latitude, final double longitude, final ReverseGeocoderCallback callback) { if (cache != null) { String cachedAddress = cache.get(new AbstractMap.SimpleImmutableEntry<>(latitude, longitude)); if (cachedAddress != null) { callback.onResult(cachedAddress); return; } } Context.getAsyncHttpClient().prepareGet(String.format(url, latitude, longitude)) .execute(new AsyncCompletionHandler() { @Override public Object onCompleted(Response response) throws Exception { try (JsonReader reader = Json.createReader(response.getResponseBodyAsStream())) { Address address = parseAddress(reader.readObject()); if (address != null) { String formattedAddress = format.format(address); if (cache != null) { cache.put(new AbstractMap.SimpleImmutableEntry<>(latitude, longitude), formattedAddress); } callback.onResult(formattedAddress); } else { callback.onResult(null); } } return null; } @Override public void onThrowable(Throwable t) { callback.onResult(null); } }); } public abstract Address parseAddress(JsonObject json); }