Add basic JMX functionality

LICENSE

@@ -5,7 +5,6 @@ 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,

ivy/ivy.xml

@@ -6,7 +6,7 @@
   </configurations>
   <dependencies>
     <dependency org="junit" name="junit" rev="4.5" conf="test->*"/>
-    <dependency org="net.sf.ehcache" name="ehcache" rev="1.5.0" conf="default->*;test->*">
+    <dependency org="net.sf.ehcache" name="ehcache" rev="1.5.0" conf="default->*;test->default">
         <exclude module="jta" />
         <exclude module="servlet" />
         <exclude module="hibernate" />

src/main/java/com/eternus/ratelimit/Enablable.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2009 James Abley
+ * 
+ * Licensed 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 com.eternus.ratelimit;
+
+/**
+ * Interface defining whether a service can be enabled or not.
+ * 
+ * @author jabley
+ *
+ */
+public interface Enablable {
+
+    /**
+     * Returns true if this service is enabled, otherwise false.
+     * 
+     * @return true if this service is enabled, otherwise false
+     */
+    boolean isEnabled();
+
+    /**
+     * Sets the enabled state of this service.
+     * 
+     * @param enabled
+     *            the enabled state
+     */
+    void setEnabled(boolean enabled);
+
+}

src/main/java/com/eternus/ratelimit/FixedBucket.java

@@ -114,4 +114,13 @@ public boolean isEnabled() {
         return enabled;
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    public void setEnabled(boolean enabled) {
+        this.enabled = enabled;
+    }
+
+
+
 }

src/main/java/com/eternus/ratelimit/RateLimiter.java

@@ -21,7 +21,7 @@
  * @author jabley
  * 
  */
-public interface RateLimiter {
+public interface RateLimiter extends Enablable {
 
     /**
      * Method called by clients to check whether they should service the current request or not. Returns a non-null

src/main/java/com/eternus/ratelimit/jmx/ManagedRateLimiter.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2009 James Abley
+ * 
+ * Licensed 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 com.eternus.ratelimit.jmx;
+
+import javax.management.MBeanNotificationInfo;
+import javax.management.Notification;
+import javax.management.NotificationBroadcasterSupport;
+import javax.management.monitor.MonitorNotification;
+
+import com.eternus.ratelimit.Key;
+import com.eternus.ratelimit.RateLimiter;
+import com.eternus.ratelimit.Token;
+
+/**
+ * JMX MBean which will send out notifications around a {@link RateLimiter} implementation.
+ * 
+ * @author jabley
+ * 
+ */
+public class ManagedRateLimiter extends NotificationBroadcasterSupport implements RateLimiter, ManagedRateLimiterMBean {
+
+    /**
+     * The name of the JXM notification that will be sent for successfully serviced requests.
+     */
+    private static final String JMX_MONITOR_RATE_LIMIT_SERVICE_TYPE = "jmx.monitor.rate-limit.service";
+
+    /**
+     * The non-null delegate.
+     */
+    private final RateLimiter delegate;
+
+    /**
+     * The JMX notification sequence number.
+     */
+    private long sequenceNumber;
+
+    /**
+     * Creates a new {@link ManagedRateLimiter} which will delegate the implementation to the specified non-null
+     * {@link RateLimiter}.
+     * 
+     * @param delegate
+     *            a non-null {@link RateLimiter} around which this MBean will send notifications
+     */
+    public ManagedRateLimiter(RateLimiter delegate) {
+        if (delegate == null) {
+            throw new IllegalArgumentException("delegate cannot be null");
+        }
+        this.delegate = delegate;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public MBeanNotificationInfo[] getNotificationInfo() {
+        String[] types = new String[] { JMX_MONITOR_RATE_LIMIT_SERVICE_TYPE,
+                MonitorNotification.THRESHOLD_VALUE_EXCEEDED };
+        MBeanNotificationInfo info = new MBeanNotificationInfo(types, Notification.class.getName(),
+                "rate-limited request processed");
+        return new MBeanNotificationInfo[] { info };
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public Token getToken(Key key) {
+        Token token = delegate.getToken(key);
+
+        if (token.isUsable()) {
+            sendNotification(new Notification(JMX_MONITOR_RATE_LIMIT_SERVICE_TYPE, this, getSequenceNumber(),
+                    "allowed request " + key));
+        } else {
+            sendNotification(new Notification(MonitorNotification.THRESHOLD_VALUE_EXCEEDED, this, getSequenceNumber(),
+                    "denied request " + key));
+        }
+
+        return token;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public boolean isEnabled() {
+        return this.delegate.isEnabled();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public void setEnabled(boolean enabled) {
+        this.delegate.setEnabled(enabled);
+    }
+
+    /**
+     * Returns the next sequence number for the JMX notification.
+     * 
+     * @return the next positive sequence number
+     */
+    private synchronized long getSequenceNumber() {
+        return ++this.sequenceNumber;
+    }
+
+}

src/main/java/com/eternus/ratelimit/jmx/ManagedRateLimiterMBean.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2009 James Abley
+ * 
+ * Licensed 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 com.eternus.ratelimit.jmx;
+
+import com.eternus.ratelimit.Enablable;
+import com.eternus.ratelimit.RateLimiter;
+
+/**
+ * MBean interface for managing {@link RateLimiter}s.
+ * 
+ * @author jabley
+ *
+ */
+public interface ManagedRateLimiterMBean extends Enablable {
+
+}