/* * 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 org.traccar.helper.Log; import javax.json.Json; import javax.json.JsonObject; import javax.json.JsonReader; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.URL; import java.util.AbstractMap; import java.util.LinkedHashMap; import java.util.Map; public abstract class JsonReverseGeocoder implements ReverseGeocoder { private final String url; private Map, String> cache; public JsonReverseGeocoder(String url, final int cacheSize) { this.url = url; if (cacheSize > 0) { this.cache = new LinkedHashMap, String>() { protected boolean removeEldestEntry(Map.Entry eldest) { return size() > cacheSize; } }; } } @Override public String getAddress(AddressFormat format, double latitude, double longitude) { if (cache != null) { String cachedAddress = cache.get(new AbstractMap.SimpleImmutableEntry<>(latitude, longitude)); if (cachedAddress != null) { return cachedAddress; } } try { HttpURLConnection conn = (HttpURLConnection) new URL(String.format(url, latitude, longitude)).openConnection(); conn.setRequestProperty("Connection", "close"); // don't keep-alive connections try { InputStreamReader streamReader = new InputStreamReader(conn.getInputStream()); try (JsonReader reader = Json.createReader(streamReader)) { Address address = parseAddress(reader.readObject()); while (streamReader.read() > 0); // make sure we reached the end if (address != null) { String formattedAddress = format.format(address); if (cache != null) { cache.put(new AbstractMap.SimpleImmutableEntry<>(latitude, longitude), formattedAddress); } return formattedAddress; } } } finally { conn.disconnect(); } } catch(Exception error) { Log.warning(error); } return null; } protected abstract Address parseAddress(JsonObject json); }