--- CircuitBreaker/src/dk/thoerup/curcuitbreaker/CircuitBreaker.java	2009/10/08 20:39:39	424
+++ miscJava/CircuitBreaker/src/main/java/dk/thoerup/circuitbreaker/CircuitBreaker.java	2015/06/09 09:28:14	2572
@@ -1,9 +1,16 @@
-package dk.thoerup.curcuitbreaker;
+package dk.thoerup.circuitbreaker;
 
-import java.util.logging.Logger;
 
-import dk.thoerup.curcuitbreaker.notification.Notifier;
-import dk.thoerup.curcuitbreaker.notification.NullNotifier;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+import dk.thoerup.circuitbreaker.config.BreakerConfig;
+import dk.thoerup.circuitbreaker.config.StaticConfig;
+import dk.thoerup.circuitbreaker.notification.NotiferHelper;
+import dk.thoerup.circuitbreaker.notification.Notifier;
+import dk.thoerup.circuitbreaker.notification.NullNotifier;
+import dk.thoerup.circuitbreaker.statistics.NullStatistics;
+import dk.thoerup.circuitbreaker.statistics.Statistics;
 
 /* Simple CircuitBreaker implementation - snipped from http://www.jroller.com/kenwdelong/entry/circuit_breaker_in_java
  * 
@@ -32,7 +39,7 @@
 		try {
 			String s = (String) cb.invoke(new TestInvocation("http://rafiki/test"));
 			response.getWriter().print(s);
-		} catch (Throwable e) {
+		} catch (Exception e) {
 			logger.warning( e.getMessage() );
 			response.sendError(500);
 			return;
@@ -43,10 +50,8 @@
 
 
 public class CircuitBreaker{
-	Logger logger = Logger.getLogger(CircuitBreaker.class.getName());
-
 	
-	private CircuitBreakerState currentState;
+	private volatile CircuitBreakerState currentState;
 	
 	private final OpenState open = new OpenState();
 	private final HalfOpenState halfOpen = new HalfOpenState();
@@ -54,20 +59,36 @@
 	
 	private String name;
 	
+	private ExecutorService executor = null;	
 	private Notifier notifier = new NullNotifier();
+	private Statistics stats = new NullStatistics();
 	
-	public CircuitBreaker(String name, int threshold, long timeoutMS) {
-		closed.setThreshold(threshold);
-		open.setTimeout(timeoutMS);
+	@Deprecated
+	public CircuitBreaker(String name, int threshold, int timeoutMS) {
+		this(name, new StaticConfig(threshold, timeoutMS) );
+	}
+	
+	public CircuitBreaker(String name, BreakerConfig config) {
+		closed.setThreshold(config);
+		open.setTimeout(config);
 		
 		this.name = name;
-		
-		reset();
+	
+		//set correct intial state
+		internalReset();
 	}
 	
+	public synchronized void shutdown() {
+		if (executor != null) {
+			executor.shutdown();
+		}
+	}
 	
-    public Object invoke(CircuitInvocation invocation) throws Throwable
+	
+    public Object invoke(CircuitInvocation invocation) throws Exception
     {
+    	stats.addStatistics(Event.Invocation);
+    	
     	Object result = null;
         try
         {
@@ -75,38 +96,68 @@
             result = invocation.proceed();
             getState().postInvoke(this);
         }
-        catch(Throwable t)
-        {
-            getState().onError(this, t);
-            throw t;
+        catch(Exception e)
+        {        	
+			if (e instanceof CircuitBreakerException) {
+				stats.addStatistics(Event.InvocationBlocked);
+			} else {
+				stats.addStatistics(Event.InvocationFailure);
+			}
+        	
+            getState().onError(this, e);
+            throw e;
         }
         return result;
     }
     
     public void tripBreaker() {
-    	synchronized(this) {
-    		open.trip();
-    		currentState = open;
-    		
-    		notifier.sendNotification(name, Notifier.Event.BreakerTripped);
-    	}    
+    	commonTripBreaker(Event.BreakerTripped);
     }
     
+	//a re-trip should basically do the same as a normal trip, but it is here just to differentiate the two different events
+    public void retripBreaker() {
+    	commonTripBreaker(Event.BreakerRetripped);
+    }
+    
+    private void commonTripBreaker(Event event) {
+       	synchronized(this) {
+    		if (currentState != open) { // TODO:Is this conditional necessary ??
+    			open.trip();
+    			currentState = open;
+    		
+    			notifier.sendNotification(this, event);
+    			stats.addStatistics(event);
+    		}
+    	}   	
+    }
+
     public void attemptReset() {
     	synchronized(this) {
-    		currentState = halfOpen;
-        	notifier.sendNotification(name, Notifier.Event.BreakerAttemptReset);
+    		if (currentState != halfOpen) { // TODO:Is this conditional necessary ??
+    			currentState = halfOpen;
+    			notifier.sendNotification(this, Event.BreakerAttemptReset);
+    			stats.addStatistics(Event.BreakerAttemptReset);
+    		}
     	}
     	
     }
     
     public void reset() {
     	synchronized(this) {
-    		currentState = closed;
-        	notifier.sendNotification(name, Notifier.Event.BreakerReset);
+    		if (currentState != closed) { // TODO: Is this conditional necessary ??
+    			internalReset();
+    			notifier.sendNotification(this, Event.BreakerReset);
+    			stats.addStatistics(Event.BreakerReset);
+    		}
     	}
     }
     
+    //This one actually sets the correct closed/reset state 
+    private void internalReset() {
+		closed.resetFailureCount();
+		currentState = closed;    	
+    }
+    
     
     private CircuitBreakerState getState() {
     	synchronized(this) {
@@ -114,6 +165,14 @@
     	}
     }
     
+    public boolean isClosed() {
+    	return (getState() == closed); 
+    }
+    
+    public boolean isOpen() {
+    	return (getState() == open); 
+    }
+    
     public String getName() {
     	return name;
     }
@@ -147,11 +206,31 @@
     }
     
     public void setNotifier(Notifier notifier) {
-    	this.notifier = notifier;
+    	synchronized(this) {
+    		this.notifier = notifier;
+    	}
+    }
+    
+    public String getNotifierName() { 
+    	return NotiferHelper.getName(notifier);
+    }
+    
+    public void setStatistics(Statistics newStats) {
+    	this.stats = newStats;
+    }
+    
+    public Statistics getStatistics() {
+    	return this.stats;
     }
     
-    public String getNotifierName() {
-    	return notifier.getClass().getName();
+    public synchronized ExecutorService getExecutor() {
+    	
+    	if (executor == null) {
+    		executor = Executors.newFixedThreadPool(1);
+    	}
+    	
+    	return executor;
+    	
     }
  
 }