diff -r 000000000000 -r ad210aa137a4 org/sonews/util/TimeoutMap.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/org/sonews/util/TimeoutMap.java	Thu Aug 06 18:34:10 2009 +0200
@@ -0,0 +1,145 @@
+/*
+ *   SONEWS News Server
+ *   see AUTHORS for the list of contributors
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.sonews.util;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Implementation of a Map that will loose its stored values after a 
+ * configurable amount of time.
+ * This class may be used to cache config values for example.
+ * @author Christian Lins
+ * @since sonews/0.5.0
+ */
+public class TimeoutMap<K,V> extends ConcurrentHashMap<K, V>
+{
+  
+  private static final long serialVersionUID = 453453467700345L;
+
+  private int                    timeout     = 60000; // 60 sec
+  private transient Map<K, Long> timeoutMap  = new HashMap<K, Long>();
+  
+  /**
+   * Constructor.
+   * @param timeout Timeout in milliseconds
+   */
+  public TimeoutMap(final int timeout)
+  {
+    this.timeout = timeout;
+  }
+  
+  /**
+   * Uses default timeout (60 sec).
+   */
+  public TimeoutMap()
+  {
+  }
+  
+  /**
+   * 
+   * @param key
+   * @return true if key is still valid.
+   */
+  protected boolean checkTimeOut(Object key)
+  {
+    synchronized(this.timeoutMap)
+    {
+      if(this.timeoutMap.containsKey(key))
+      {
+        long keytime = this.timeoutMap.get(key);
+        if((System.currentTimeMillis() - keytime) < this.timeout)
+        {
+          return true;
+        }
+        else
+        {
+          remove(key);
+          return false;
+        }
+      }
+      else
+      {
+        return false;
+      }
+    }
+  }
+  
+  @Override
+  public boolean containsKey(Object key)
+  {
+    return checkTimeOut(key);
+  }
+
+  @Override
+  public synchronized V get(Object key)
+  {
+    if(checkTimeOut(key))
+    {
+      return super.get(key);
+    }
+    else
+    {
+      return null;
+    }
+  }
+
+  @Override
+  public V put(K key, V value)
+  {
+    synchronized(this.timeoutMap)
+    {
+      removeStaleKeys();
+      this.timeoutMap.put(key, System.currentTimeMillis());
+      return super.put(key, value);
+    }
+  }
+
+  /**
+   * @param arg0
+   * @return
+   */
+  @Override
+  public V remove(Object arg0)
+  {
+    synchronized(this.timeoutMap)
+    {
+      this.timeoutMap.remove(arg0);
+      V val = super.remove(arg0);
+      return val;
+    }
+  }
+
+  protected void removeStaleKeys()
+  {
+    synchronized(this.timeoutMap)
+    {
+      Set<Object> keySet = new HashSet<Object>(this.timeoutMap.keySet());
+      for(Object key : keySet)
+      {
+        // The key/value is removed by the checkTimeOut() method if true
+        checkTimeOut(key);
+      }
+    }
+  }
+  
+}