[jrugged] r288 committed - Deleted wiki page CircuitBreakerExceptionMapper through web user inter...

[jru...@googlecode.com]

Revision: 288
Author: joseph.r...@gmail.com
Date: Thu Nov 22 06:08:19 2012
Log: Deleted wiki page CircuitBreakerExceptionMapper through web user
interface.
http://code.google.com/p/jrugged/source/detail?r=288

Deleted:
/wiki/CircuitBreakerExceptionMapper.wiki

=======================================
--- /wiki/CircuitBreakerExceptionMapper.wiki Thu Dec 2 06:22:26 2010
+++ /dev/null
@@ -1,85 +0,0 @@
-#summary Examples for how to take a CircuitBreakerException and
automatically turn it into an exception meaningful to the application you
may be writing.
-
-= Introduction =
-
-Circuitbreakers include the ability to take the thrown
[http://jrugged.s3.amazonaws.com/jrugged-core-2.2.0/apidocs/org/fishwife/jrugged/CircuitBreakerException.html
CircuitBreakerException] and turn it into another exception so that your
application code need not know anything about
[http://jrugged.s3.amazonaws.com/jrugged-core-2.2.0/apidocs/org/fishwife/jrugged/CircuitBreakerException.html
CircuitBreakerException], but rather know about an exception of your
choosing. Below is the detail about a simple mapping of
[http://jrugged.s3.amazonaws.com/jrugged-core-2.2.0/apidocs/org/fishwife/jrugged/CircuitBreakerException.html
CircuitBreakerException] into a basic application exception.
-
-= Details =
-
-The only “gotcha” is: The mapped exception must be either a
`RuntimeException` (or child) or must be declared as thrown by the
intercepted method. Otherwise, Java will throw an
`UndeclaredThrowableException` at runtime.
-
-Here’s what it took...
-Add the mapper declaration to the `CircuitBreakerBean` declaration:
-
-{{{
-<constructor-arg>
- <bean
class="net.applicaiton.device.service.AppCircuitBreakerExceptionMapper" />
-</constructor-arg>
-}}}
-
-... as in:
-
-{{{
-<bean id="appCircuitBreaker"
class="org.fishwife.jrugged.spring.CircuitBreakerBean">
- <constructor-arg>
- <bean
class="net.applicaiton.device.service.AppCircuitBreakerExceptionMapper" />
- </constructor-arg>
- <property name="limit" value="3"/>
- <property name="windowMillis" value="5000"/>
- <property name="resetMillis" value="20000"/>
-</bean>
-}}}
-
-{{{
-public class AppCircuitBreakerExceptionMapper implements
CircuitBreakerExceptionMapper<AppCircuitBreakerException> {
- @Override
- public AppCircuitBreakerException map(CircuitBreaker breaker,
CircuitBreakerException exception) {
- return new AppCircuitBreakerException(exception.getCause());
- }
-}
-}}}
-
-{{{
-/*
- * Use a runtime exception child to differentiate between the intercepted
exception and the
- * “thrown by circuitbreaker” exception (rather than mapping to what
originally tripped the circuit).
- * This is most useful when more than one external system is
circuit-broken and you want to
- * know which one threw. I’m not sure how to handle method-level
granularity.
- */
-public class AppCircuitBreakerException extends RuntimeException {
- public AppCircuitBreakerException(Throwable cause) {
- super(cause);
- }
-}
-}}}
-
-This example uses an existing, declared Exception (named `ThingException`)
rather than a `RuntimeException`. In this case, the throws declaration of
the method must match the parameterized mapper declaration.
-
-This method:
-{{{
-public THing getThingFromId(String ID) throws ThingException {
-...
-}
-}}}
-
-Is mapped by:
-{{{
-<bean id="appCircuitBreaker"
class="org.fishwife.jrugged.spring.CircuitBreakerBean">
- <constructor-arg>
- <bean
class="net.comcast.cim.device.service.PlatformCircuitBreakerExceptionMapper"
/>
- </constructor-arg>
- <property name="limit" value="3"/>
- <property name="windowMillis" value="5000"/>
- <property name="resetMillis" value="20000"/>
-</bean>
-}}}
-
-Using this Mapper:
-{{{
-public class AppBreakerExceptionMapper implements
CircuitBreakerExceptionMapper<ThingException> {
- @Override
- public ThingException map(CircuitBreaker breaker,
CircuitBreakerException exception) {
- return new ThingException(AppError.TP_CIRCUIT_BREAKER_TRIPPED,
exception);
- }
-}
-}}}