9 |
import dk.thoerup.circuitbreaker.notification.NotiferHelper; |
import dk.thoerup.circuitbreaker.notification.NotiferHelper; |
10 |
import dk.thoerup.circuitbreaker.notification.Notifier; |
import dk.thoerup.circuitbreaker.notification.Notifier; |
11 |
import dk.thoerup.circuitbreaker.notification.NullNotifier; |
import dk.thoerup.circuitbreaker.notification.NullNotifier; |
12 |
|
import dk.thoerup.circuitbreaker.statistics.NullStatistics; |
13 |
|
import dk.thoerup.circuitbreaker.statistics.Statistics; |
14 |
|
|
15 |
/* Simple CircuitBreaker implementation - snipped from http://www.jroller.com/kenwdelong/entry/circuit_breaker_in_java |
/* Simple CircuitBreaker implementation - snipped from http://www.jroller.com/kenwdelong/entry/circuit_breaker_in_java |
16 |
* |
* |
61 |
|
|
62 |
private ExecutorService executor = null; |
private ExecutorService executor = null; |
63 |
private Notifier notifier = new NullNotifier(); |
private Notifier notifier = new NullNotifier(); |
64 |
|
private Statistics stats = new NullStatistics(); |
65 |
|
|
66 |
@Deprecated |
@Deprecated |
67 |
public CircuitBreaker(String name, int threshold, int timeoutMS) { |
public CircuitBreaker(String name, int threshold, int timeoutMS) { |
87 |
|
|
88 |
public Object invoke(CircuitInvocation invocation) throws Exception |
public Object invoke(CircuitInvocation invocation) throws Exception |
89 |
{ |
{ |
90 |
|
stats.addStatistics(Event.Invocation); |
91 |
|
|
92 |
Object result = null; |
Object result = null; |
93 |
try |
try |
94 |
{ |
{ |
97 |
getState().postInvoke(this); |
getState().postInvoke(this); |
98 |
} |
} |
99 |
catch(Exception e) |
catch(Exception e) |
100 |
{ |
{ |
101 |
|
if (e instanceof CircuitBreakerException) { |
102 |
|
stats.addStatistics(Event.InvocationBlocked); |
103 |
|
} else { |
104 |
|
stats.addStatistics(Event.InvocationFailure); |
105 |
|
} |
106 |
|
|
107 |
getState().onError(this, e); |
getState().onError(this, e); |
108 |
throw e; |
throw e; |
109 |
} |
} |
111 |
} |
} |
112 |
|
|
113 |
public void tripBreaker() { |
public void tripBreaker() { |
114 |
commonTripBreaker(Notifier.Event.BreakerTripped); |
commonTripBreaker(Event.BreakerTripped); |
115 |
} |
} |
116 |
|
|
117 |
//a re-trip should basically do the same as a normal trip, but it is here just to differentiate the two different events |
//a re-trip should basically do the same as a normal trip, but it is here just to differentiate the two different events |
118 |
public void retripBreaker() { |
public void retripBreaker() { |
119 |
commonTripBreaker(Notifier.Event.BreakerRetripped); |
commonTripBreaker(Event.BreakerRetripped); |
120 |
} |
} |
121 |
|
|
122 |
private void commonTripBreaker(Notifier.Event event) { |
private void commonTripBreaker(Event event) { |
123 |
synchronized(this) { |
synchronized(this) { |
124 |
if (currentState != open) { // TODO:Is this conditional necessary ?? |
if (currentState != open) { // TODO:Is this conditional necessary ?? |
125 |
open.trip(); |
open.trip(); |
126 |
currentState = open; |
currentState = open; |
127 |
|
|
128 |
notifier.sendNotification(this, event); |
notifier.sendNotification(this, event); |
129 |
|
stats.addStatistics(event); |
130 |
} |
} |
131 |
} |
} |
132 |
} |
} |
135 |
synchronized(this) { |
synchronized(this) { |
136 |
if (currentState != halfOpen) { // TODO:Is this conditional necessary ?? |
if (currentState != halfOpen) { // TODO:Is this conditional necessary ?? |
137 |
currentState = halfOpen; |
currentState = halfOpen; |
138 |
notifier.sendNotification(this, Notifier.Event.BreakerAttemptReset); |
notifier.sendNotification(this, Event.BreakerAttemptReset); |
139 |
|
stats.addStatistics(Event.BreakerAttemptReset); |
140 |
} |
} |
141 |
} |
} |
142 |
|
|
146 |
synchronized(this) { |
synchronized(this) { |
147 |
if (currentState != closed) { // TODO: Is this conditional necessary ?? |
if (currentState != closed) { // TODO: Is this conditional necessary ?? |
148 |
internalReset(); |
internalReset(); |
149 |
notifier.sendNotification(this, Notifier.Event.BreakerReset); |
notifier.sendNotification(this, Event.BreakerReset); |
150 |
|
stats.addStatistics(Event.BreakerReset); |
151 |
} |
} |
152 |
} |
} |
153 |
} |
} |
213 |
return NotiferHelper.getName(notifier); |
return NotiferHelper.getName(notifier); |
214 |
} |
} |
215 |
|
|
216 |
|
public void setStatistics(Statistics newStats) { |
217 |
|
this.stats = newStats; |
218 |
|
} |
219 |
|
|
220 |
|
public Statistics getStatistics() { |
221 |
|
return this.stats; |
222 |
|
} |
223 |
|
|
224 |
public synchronized ExecutorService getExecutor() { |
public synchronized ExecutorService getExecutor() { |
225 |
|
|
226 |
if (executor == null) { |
if (executor == null) { |