Java tutorial
/* * Copyright 2011 Proofpoint, Inc. * * 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 com.proofpoint.event.monitor; import com.google.common.base.Function; import com.google.common.collect.MapMaker; import com.google.common.collect.Maps; import javax.annotation.Nullable; import javax.inject.Inject; import javax.ws.rs.Consumes; import javax.ws.rs.DELETE; import javax.ws.rs.GET; import javax.ws.rs.POST; import javax.ws.rs.Path; import javax.ws.rs.Produces; import javax.ws.rs.core.MediaType; import java.util.List; import java.util.Map; import java.util.Set; import java.util.concurrent.ConcurrentMap; import java.util.concurrent.atomic.AtomicInteger; @Path("/v1/event") public class MonitorEventTapResource { private final Set<Monitor> monitors; private volatile ConcurrentMap<String, AtomicInteger> history = new MapMaker().makeMap(); @Inject public MonitorEventTapResource(Set<Monitor> monitors) { this.monitors = monitors; } @POST @Consumes(MediaType.APPLICATION_JSON) public void post(List<Event> events) { if (events.isEmpty()) { return; } for (Monitor monitor : monitors) { monitor.processEvents(events); } // Assumes batches are homogeneous String key = events.get(0).getType(); ConcurrentMap<String, AtomicInteger> historyRef = this.history; historyRef.putIfAbsent(key, new AtomicInteger(0)); historyRef.get(key).addAndGet(events.size()); } @GET @Path("/stats") @Produces(MediaType.APPLICATION_JSON) public Map<String, Integer> getStats() { return Maps.transformValues(history, new Function<AtomicInteger, Integer>() { @Override public Integer apply(@Nullable AtomicInteger atomicInteger) { return atomicInteger.get(); } }); } @DELETE @Path("/stats") public void resetStats() { history = new MapMaker().makeMap(); } }