/*
* Copyright (C) 2012-2014 the original author or authors.
*
* 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 ninja.metrics;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import com.codahale.metrics.Counter;
import com.codahale.metrics.MetricRegistry;
import com.google.inject.Inject;
import com.google.inject.Provider;
/**
*
* @author James Moger
*/
public class CountedInterceptor implements MethodInterceptor {
final Provider<MetricsService> metricsServiceProvider;
@Inject
public CountedInterceptor(Provider<MetricsService> metricsServiceProvider) {
this.metricsServiceProvider = metricsServiceProvider;
}
@Override
public Object invoke(MethodInvocation invocation) throws Throwable {
Counted counted = invocation.getMethod().getAnnotation(Counted.class);
String counterName = counted.value();
if (counterName.isEmpty()) {
counterName = MetricRegistry.name(invocation.getThis().getClass()
.getSuperclass(), invocation.getMethod().getName());
}
Counter counter = metricsServiceProvider.get().getMetricRegistry()
.counter(counterName);
counter.inc();
try {
return invocation.proceed();
} finally {
if (counted.active()) {
counter.dec();
}
}
}
}