# TimingCaptureAllConcern.java

    /*
     * Copyright (c) 2012, Niclas Hedhman. All Rights Reserved.
     *
     * 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 org.qi4j.library.metrics;

    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.Method;
    import java.util.concurrent.TimeUnit;
    import org.qi4j.api.common.Optional;
    import org.qi4j.api.concern.ConcernOf;
    import org.qi4j.api.injection.scope.Invocation;
    import org.qi4j.api.injection.scope.Service;
    import org.qi4j.api.metrics.MetricsProvider;
    import org.qi4j.api.metrics.MetricsTimer;
    import org.qi4j.api.metrics.MetricsTimerFactory;

    public class TimingCaptureAllConcern extends ConcernOf<InvocationHandler>
        implements InvocationHandler
    {
        private MetricsTimer timer;

        public TimingCaptureAllConcern( @Service @Optional MetricsProvider metrics,
                                        @Invocation Method method
        )
        {
            if( metrics != null )
            {
                MetricsTimerFactory factory = metrics.createFactory( MetricsTimerFactory.class );
                boolean annotated = method.getAnnotation( TimingCapture.class ) != null;
                String captureNme = getMethodName( method ) + "() ["  +( annotated ? "@" : "" ) + "TimingCapture" + "]";
                Class<?> declaringClass = method.getDeclaringClass();
                timer = factory.createTimer( declaringClass, captureNme, TimeUnit.MILLISECONDS, TimeUnit.SECONDS );
            }
        }

        private String getMethodName( Method method )
        {
            return method.getName();
        }

        @Override
        public Object invoke( Object proxy, Method method, Object[] args )
            throws Throwable
        {
            MetricsTimer.Context timing = null;
            if( timer != null )
            {
                timing = timer.start();
            }
            try
            {
                return next.invoke( proxy, method, args );
            }
            finally
            {
                if( timing != null )
                {
                    timing.stop();
                }
            }
        }
    }