svn commit: r550032 - /mina/trunk/core/src/main/java/org/apache/mina/filter/ConnectionThrottleFilter.java

[mw...@apache.org]

Author: mwebb
Date: Sat Jun 23 05:03:10 2007
New Revision: 550032

URL: http://svn.apache.org/viewvc?view=rev&rev=550032
Log:
initial creation.  This was written in response to JIRA #389

Added:
    mina/trunk/core/src/main/java/org/apache/mina/filter/ConnectionThrottleFilter.java

Added: mina/trunk/core/src/main/java/org/apache/mina/filter/ConnectionThrottleFilter.java
URL: http://svn.apache.org/viewvc/mina/trunk/core/src/main/java/org/apache/mina/filter/ConnectionThrottleFilter.java?view=auto&rev=550032
==============================================================================
--- mina/trunk/core/src/main/java/org/apache/mina/filter/ConnectionThrottleFilter.java (added)
+++ mina/trunk/core/src/main/java/org/apache/mina/filter/ConnectionThrottleFilter.java Sat Jun 23 05:03:10 2007
@@ -0,0 +1,104 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one
+ *  or more contributor license agreements.  See the NOTICE file
+ *  distributed with this work for additional information
+ *  regarding copyright ownership.  The ASF licenses this file
+ *  to you under the Apache License, Version 2.0 (the
+ *  "License"); you may not use this file except in compliance
+ *  with the License.  You may obtain a copy of the License at
+ *  
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *  
+ *  Unless required by applicable law or agreed to in writing,
+ *  software distributed under the License is distributed on an
+ *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ *  KIND, either express or implied.  See the License for the
+ *  specific language governing permissions and limitations
+ *  under the License. 
+ *  
+ */
+package org.apache.mina.filter;
+
+import java.net.InetSocketAddress;
+import java.net.SocketAddress;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.mina.common.IoFilter;
+import org.apache.mina.common.IoFilterAdapter;
+import org.apache.mina.common.IoSession;
+import org.apache.mina.util.SessionLog;
+
+/**
+ * A {@link IoFilter} which blocks connections from connecting
+ * at a rate faster than the specified interval.
+ * 
+ * @author The Apache MINA Project (dev@mina.apache.org)
+ * @version $Rev $
+ */
+public class ConnectionThrottleFilter extends IoFilterAdapter {
+    private static final long DEFAULT_TIME = 1000;  
+    private long allowedInterval;
+    private final Map<String,Long> clients;
+
+    /**
+     * Default constructor.  Sets the wait time to 1 second
+     */
+    public ConnectionThrottleFilter() {
+        this( DEFAULT_TIME );
+    }
+
+    /**
+     * Constructor that takes in a specified wait time.
+     * 
+     * @param allowedInterval
+     * 	The number of milliseconds a client is allowed to wait
+     * 	before making another successful connection
+     * 
+     */
+    public ConnectionThrottleFilter( long allowedInterval ){
+        this.allowedInterval = allowedInterval;
+        clients = Collections.synchronizedMap( new HashMap<String,Long>());
+    }
+
+    /**
+     * Sets the interval between connections from a client. 
+     * This value is measured in milliseconds.
+     * 
+     * @param allowedInterval
+     * 	The number of milliseconds a client is allowed to wait
+     * 	before making another successful connection
+     */
+    public void setAllowedInterval(long allowedInterval) {
+        this.allowedInterval = allowedInterval;
+    }
+
+    private synchronized boolean isConnectionOk( IoSession session ){
+        SocketAddress remoteAddress = session.getRemoteAddress();
+        if( remoteAddress instanceof InetSocketAddress )
+        {
+            long now = System.currentTimeMillis();
+            InetSocketAddress addr = (InetSocketAddress)remoteAddress;
+            if( clients.containsKey(addr.getAddress().getHostAddress())){
+                Long time = clients.get(addr.getAddress().getHostAddress());
+                if( (now-time) > allowedInterval ){
+                    return false;
+                }
+            } else {
+                clients.put( addr.getAddress().getHostAddress(), now );
+                return true;
+            }
+        }
+       
+        return false;
+    }
+   
+    @Override
+    public void sessionCreated(NextFilter nextFilter, IoSession session) throws Exception {
+        if( ! isConnectionOk(session)){
+             SessionLog.info( session, "Connections coming in too fast; closing." );
+             session.close();
+        }
+    }
+}
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