Implement geocoder address caching

5 files changed, 42 insertions, 12 deletions

diff --git a/src/org/traccar/Context.java b/src/org/traccar/Context.java
index 7b364d799..a25f2f65e 100644
--- a/src/org/traccar/Context.java
+++ b/src/org/traccar/Context.java
@@ -109,15 +109,16 @@ public class Context {
         if (config.getBoolean("geocoder.enable")) {
             String type = config.getString("geocoder.type", "google");
             String url = config.getString("geocoder.url");
+            int cacheSize = config.getInteger("geocoder.cacheSize");
             switch (type) {
                 case "google":
-                    reverseGeocoder = new GoogleReverseGeocoder();
+                    reverseGeocoder = new GoogleReverseGeocoder(cacheSize);
                     break;
                 case "nominatim":
-                    reverseGeocoder = new NominatimReverseGeocoder(url);
+                    reverseGeocoder = new NominatimReverseGeocoder(url, cacheSize);
                     break;
                 case "gisgraphy":
-                    reverseGeocoder = new GisgraphyReverseGeocoder(url);
+                    reverseGeocoder = new GisgraphyReverseGeocoder(url, cacheSize);
                     break;
             }
         }
diff --git a/src/org/traccar/geocode/GisgraphyReverseGeocoder.java b/src/org/traccar/geocode/GisgraphyReverseGeocoder.java
index 392a11e66..6e0e5a343 100644
--- a/src/org/traccar/geocode/GisgraphyReverseGeocoder.java
+++ b/src/org/traccar/geocode/GisgraphyReverseGeocoder.java
@@ -26,11 +26,11 @@ import java.net.URLConnection;
 public class GisgraphyReverseGeocoder extends JsonReverseGeocoder {
 
     public GisgraphyReverseGeocoder() {
-        this("http://services.gisgraphy.com/street/streetsearch");
+        this("http://services.gisgraphy.com/street/streetsearch", 0);
     }
 
-    public GisgraphyReverseGeocoder(String url) {
-        super(url + "?format=json&lat=%f&lng=%f&from=1&to=1");
+    public GisgraphyReverseGeocoder(String url, int cacheSize) {
+        super(url + "?format=json&lat=%f&lng=%f&from=1&to=1", cacheSize);
     }
 
     @Override
diff --git a/src/org/traccar/geocode/GoogleReverseGeocoder.java b/src/org/traccar/geocode/GoogleReverseGeocoder.java
index c37d4188f..667436cbe 100644
--- a/src/org/traccar/geocode/GoogleReverseGeocoder.java
+++ b/src/org/traccar/geocode/GoogleReverseGeocoder.java
@@ -22,7 +22,11 @@ import javax.json.JsonString;
 public class GoogleReverseGeocoder extends JsonReverseGeocoder {
 
     public GoogleReverseGeocoder() {
-        super("http://maps.googleapis.com/maps/api/geocode/json?latlng=%f,%f");
+        this(0);
+    }
+
+    public GoogleReverseGeocoder(int cacheSize) {
+        super("http://maps.googleapis.com/maps/api/geocode/json?latlng=%f,%f", cacheSize);
     }
 
     @Override
diff --git a/src/org/traccar/geocode/JsonReverseGeocoder.java b/src/org/traccar/geocode/JsonReverseGeocoder.java
index c43641245..442b8551c 100644
--- a/src/org/traccar/geocode/JsonReverseGeocoder.java
+++ b/src/org/traccar/geocode/JsonReverseGeocoder.java
@@ -25,18 +25,37 @@ import java.io.Reader;
 import java.net.HttpURLConnection;
 import java.net.URL;
 import java.net.URLConnection;
+import java.util.AbstractMap;
+import java.util.LinkedHashMap;
+import java.util.Map;
 
 public abstract class JsonReverseGeocoder implements ReverseGeocoder {
 
     private final String url;
 
-    public JsonReverseGeocoder(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 = new LinkedHashMap<Map.Entry<Double, Double>, 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
@@ -46,7 +65,13 @@ public abstract class JsonReverseGeocoder implements ReverseGeocoder {
                     Address address = parseAddress(reader.readObject());
                     while (streamReader.read() > 0); // make sure we reached the end
                     if (address != null) {
-                        return format.format(address);
+                        String formattedAddress = format.format(address);
+
+                        if (cache != null) {
+                            cache.put(new AbstractMap.SimpleImmutableEntry<>(latitude, longitude), formattedAddress);
+                        }
+
+                        return formattedAddress;
                     }
                 }
             } finally {
diff --git a/src/org/traccar/geocode/NominatimReverseGeocoder.java b/src/org/traccar/geocode/NominatimReverseGeocoder.java
index 27c241c66..96c9a993d 100644
--- a/src/org/traccar/geocode/NominatimReverseGeocoder.java
+++ b/src/org/traccar/geocode/NominatimReverseGeocoder.java
@@ -30,11 +30,11 @@ import org.w3c.dom.Document;
 public class NominatimReverseGeocoder extends JsonReverseGeocoder {
 
     public NominatimReverseGeocoder() {
-        this("http://nominatim.openstreetmap.org/reverse");
+        this("http://nominatim.openstreetmap.org/reverse", 0);
     }
     
-    public NominatimReverseGeocoder(String url) {
-        super(url + "?format=json&lat=%f&lon=%f&zoom=18&addressdetails=1");
+    public NominatimReverseGeocoder(String url, int cacheSize) {
+        super(url + "?format=json&lat=%f&lon=%f&zoom=18&addressdetails=1", cacheSize);
     }
 
     @Override