Make the cache cache synchronized

Concurrent modifications could occur, especially on very large displays
where we may have to draw a lot of caches at the same time while
fetching others. This could lead to ConcurrentModificationException
errors, as described in #1706.

1 files changed, 13 insertions, 7 deletions

diff --git a/main/src/cgeo/geocaching/CacheCache.java b/main/src/cgeo/geocaching/CacheCache.java
index e8280e2..877c960 100644
--- a/main/src/cgeo/geocaching/CacheCache.java
+++ b/main/src/cgeo/geocaching/CacheCache.java
@@ -27,7 +27,7 @@ public class CacheCache {
         cachesCache.setRemoveHandler(new CacheRemoveHandler());
     }
 
-    public void removeAllFromCache() {
+    public synchronized void removeAllFromCache() {
         cachesCache.clear();
     }
 
@@ -39,7 +39,9 @@ public class CacheCache {
         if (StringUtils.isBlank(geocode)) {
             throw new IllegalArgumentException("geocode must not be empty");
         }
-        cachesCache.remove(geocode);
+        synchronized(this) {
+            cachesCache.remove(geocode);
+        }
     }
 
     /**
@@ -56,8 +58,10 @@ public class CacheCache {
         if (StringUtils.isBlank(cache.getGeocode())) {
             throw new IllegalArgumentException("geocode must not be empty");
         }
-        cache.addStorageLocation(StorageLocation.CACHE);
-        cachesCache.put(cache.getGeocode(), cache);
+        synchronized(this) {
+            cache.addStorageLocation(StorageLocation.CACHE);
+            cachesCache.put(cache.getGeocode(), cache);
+        }
     }
 
     /**
@@ -69,10 +73,12 @@ public class CacheCache {
         if (StringUtils.isBlank(geocode)) {
             throw new IllegalArgumentException("geocode must not be empty");
         }
-        return cachesCache.get(geocode);
+        synchronized(this) {
+            return cachesCache.get(geocode);
+        }
     }
 
-    public Set<String> getInViewport(final Viewport viewport, final CacheType cacheType) {
+    public synchronized Set<String> getInViewport(final Viewport viewport, final CacheType cacheType) {
         final Set<String> geocodes = new HashSet<String>();
         for (final cgCache cache : cachesCache.values()) {
             if (cache.getCoords() == null) {
@@ -89,7 +95,7 @@ public class CacheCache {
     }
 
     @Override
-    public String toString() {
+    public synchronized String toString() {
         return StringUtils.join(cachesCache.keySet(), ' ');
     }