Java tutorial
package com.thinkbiganalytics.metadata.sla.alerts; /*- * #%L * thinkbig-sla-core * %% * Copyright (C) 2017 ThinkBig Analytics * %% * 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. * #L% */ import com.google.common.base.Predicate; import com.google.common.collect.Iterables; import com.thinkbiganalytics.metadata.sla.api.ServiceLevelAgreementAction; import com.thinkbiganalytics.metadata.sla.api.ServiceLevelAgreementActionValidation; import com.thinkbiganalytics.spring.SpringApplicationContext; import org.apache.commons.lang3.reflect.ConstructorUtils; import org.springframework.beans.factory.NoSuchBeanDefinitionException; import java.lang.reflect.InvocationTargetException; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import java.util.Map; import java.util.Timer; import java.util.TimerTask; import java.util.concurrent.ConcurrentHashMap; /** */ public class ServiceLevelAgreementActionUtil { public static Map<Class<? extends ServiceLevelAgreementAction>, Boolean> validActionCache = new ConcurrentHashMap<>(); Timer invalidActionConfigurationCacheTimer = new Timer(); public ServiceLevelAgreementActionUtil() { scheduleCacheCheck(); } public static boolean isValidConfiguration(List<Class<? extends ServiceLevelAgreementAction>> actionClasses) { List<ServiceLevelAgreementActionValidation> validation = validateActionConfiguration(actionClasses); return Iterables.any(validation, new Predicate<ServiceLevelAgreementActionValidation>() { @Override public boolean apply(ServiceLevelAgreementActionValidation serviceLevelAgreementActionValidation) { return !serviceLevelAgreementActionValidation.isValid(); } }); } public static ServiceLevelAgreementActionValidation validateConfiguration(ServiceLevelAgreementAction action) { if (validActionCache.containsKey(action.getClass()) && validActionCache.get(action.getClass()) == true) { return ServiceLevelAgreementActionValidation.VALID; } if (action != null) { ServiceLevelAgreementActionValidation validAction = action.validateConfiguration(); validAction.setActionClass(action.getClass().getName()); validActionCache.put(action.getClass(), validAction.isValid()); return validAction; } return new ServiceLevelAgreementActionValidation(false, "Unable to find SLA Action "); } public static List<ServiceLevelAgreementActionValidation> validateActionConfiguration( List<Class<? extends ServiceLevelAgreementAction>> actionClasses) { List<ServiceLevelAgreementActionValidation> validation = new ArrayList<>(); if (actionClasses != null) { for (Class<? extends ServiceLevelAgreementAction> actionClass : actionClasses) { if (validActionCache.containsKey(actionClass) && validActionCache.get(actionClass) == true) { validation.add(ServiceLevelAgreementActionValidation.valid(actionClass)); } ServiceLevelAgreementAction action = ServiceLevelAgreementActionUtil.instantiate(actionClass); if (action != null) { validation.add(validateConfiguration(action)); } } } return validation; } //re-evaluate invalid actions ever 1 hr public static ServiceLevelAgreementAction instantiate(Class<? extends ServiceLevelAgreementAction> clazz) { ServiceLevelAgreementAction action = null; try { action = SpringApplicationContext.getBean(clazz); } catch (NoSuchBeanDefinitionException e) { //this is ok } //if not spring bound then construct the Responder if (action == null) { //construct and invoke try { action = ConstructorUtils.invokeConstructor(clazz, null); } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException | InstantiationException e) { //TODO LOG error e.printStackTrace(); } } return action; } private void scheduleCacheCheck() { invalidActionConfigurationCacheTimer.schedule(new EvaluateInvalidActionsTimer(), (60 * 1000 * 5), (60 * 1000) * 60); // delay 5 min, 1 hr eval } private class EvaluateInvalidActionsTimer extends TimerTask { @Override public void run() { Iterator<Map.Entry<Class<? extends ServiceLevelAgreementAction>, Boolean>> iter = validActionCache .entrySet().iterator(); while (iter.hasNext()) { Map.Entry<Class<? extends ServiceLevelAgreementAction>, Boolean> entry = iter.next(); if (entry.getValue() != null && entry.getValue().booleanValue() == false) { iter.remove(); } } } } }