Fix: full FA refactor

src/main/java/it/polimi/ingsw/gc14/LimitedMap.java

@@ -1,15 +1,14 @@
 package it.polimi.ingsw.gc14;
 
 import java.util.Collection;
-import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
- * A {@link LinkedHashMap} with a configurable size limit and an associated action.
+ * A {@link ConcurrentHashMap}-backed map with a configurable size limit and an associated action.
  * When the number of elements reaches or exceeds the limit, the specified action is automatically triggered.
- * This implementation is thread-safe.
+ * This implementation is thread-safe for {@code put}; callers that need compound operations must synchronize externally.
  *
  * @param <K> the type of keys maintained by this map.
  * @param <V> the type of mapped values.
@@ -50,8 +49,8 @@ public class LimitedMap<K, V> implements Map<K, V> {
     @Override
     public synchronized V put(K key, V value) {
         boolean added = true;
-        if(map.size()==limit) {
-            if(!map.containsKey(key))
+        if (map.size() == limit) {
+            if (!map.containsKey(key))
                 return null;
             added = false;
         }
@@ -63,7 +62,7 @@ public class LimitedMap<K, V> implements Map<K, V> {
     }
 
     @Override
-    public V remove(Object key) { return map.remove(key); }
+    public synchronized V remove(Object key) { return map.remove(key); }
 
     @Override
     public V get(Object key) { return map.get(key); }
@@ -112,7 +111,10 @@ public class LimitedMap<K, V> implements Map<K, V> {
     /**
      * Sets a new action to execute when the map size reaches or exceeds the limit.
      *
-     * @param action the new action to set.
+     * @param action the new action to set; must not be {@code null}.
      */
-    public void setAction(Runnable action) { this.action = action; }
+    public void setAction(Runnable action) {
+        if (action == null) throw new IllegalArgumentException("action must not be null");
+        this.action = action;
+    }
 }