| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.apache.servicecomb.governance.handler; |
| |
| import java.util.Map; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| import org.apache.servicecomb.governance.MatchersManager; |
| import org.apache.servicecomb.governance.event.GovernanceConfigurationChangedEvent; |
| import org.apache.servicecomb.governance.event.GovernanceEventManager; |
| import org.apache.servicecomb.governance.marker.GovernanceRequest; |
| import org.apache.servicecomb.governance.policy.AbstractPolicy; |
| import org.springframework.beans.factory.annotation.Autowired; |
| |
| import com.google.common.eventbus.Subscribe; |
| |
| public abstract class AbstractGovernanceHandler<PROCESSOR, POLICY extends AbstractPolicy> { |
| protected final Map<String, PROCESSOR> processors = new ConcurrentHashMap<>(); |
| |
| private final Object lock = new Object(); |
| |
| protected MatchersManager matchersManager; |
| |
| @Autowired |
| public void setMatchersManager(MatchersManager matchersManager) { |
| this.matchersManager = matchersManager; |
| } |
| |
| protected AbstractGovernanceHandler() { |
| GovernanceEventManager.register(this); |
| } |
| |
| public <R> PROCESSOR getActuator(GovernanceRequest governanceRequest) { |
| POLICY policy = matchPolicy(governanceRequest); |
| if (policy == null) { |
| return null; |
| } |
| |
| String key = createKey(governanceRequest, policy); |
| PROCESSOR processor = processors.get(key); |
| if (processor == null) { |
| synchronized (lock) { |
| processor = processors.get(key); |
| if (processor == null) { |
| processor = createProcessor(governanceRequest, policy); |
| processors.put(key, processor); |
| } |
| } |
| } |
| return processor; |
| } |
| |
| protected abstract String createKey(GovernanceRequest governanceRequest, POLICY policy); |
| |
| protected abstract POLICY matchPolicy(GovernanceRequest governanceRequest); |
| |
| protected abstract PROCESSOR createProcessor(GovernanceRequest governanceRequest, POLICY policy); |
| |
| protected void onConfigurationChanged(String key) { |
| processors.remove(key); |
| } |
| |
| @Subscribe |
| public void onDynamicConfigurationListener(GovernanceConfigurationChangedEvent event) { |
| event.getChangedConfigurations().forEach(this::onConfigurationChanged); |
| } |
| } |