fix #2316: race condition in LeastRecentlyUsedSet

removeAll() must be synchronized as well. Otherwise, the documentation
states that it uses a (unsynchronized) iterator to perform the removal,
which causes race conditions.

1 files changed, 13 insertions, 0 deletions

diff --git a/main/src/cgeo/geocaching/utils/LeastRecentlyUsedSet.java b/main/src/cgeo/geocaching/utils/LeastRecentlyUsedSet.java
index 98aba03..b654fd6 100644
--- a/main/src/cgeo/geocaching/utils/LeastRecentlyUsedSet.java
+++ b/main/src/cgeo/geocaching/utils/LeastRecentlyUsedSet.java
@@ -2,6 +2,7 @@ package cgeo.geocaching.utils;
 
 import java.util.AbstractSet;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
@@ -102,6 +103,18 @@ public class LeastRecentlyUsedSet<E> extends AbstractSet<E>
     }
 
     /**
+     * Synchronized removal of all elements contained in another collection.
+     */
+    @Override
+    public synchronized boolean removeAll(final Collection<?> c) {
+        boolean changed = false;
+        for (final Object o: c) {
+            changed |= remove(o);
+        }
+        return changed;
+    }
+
+    /**
      * Synchronized clearing of the set
      * Copy of the HashSet code if clear()
      *