| /* |
| * 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.drill.exec.physical.impl; |
| |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.ParameterizedType; |
| import java.lang.reflect.Type; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.apache.drill.common.exceptions.ExecutionSetupException; |
| import org.apache.drill.common.scanner.persistence.ScanResult; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| public class OperatorCreatorRegistry { |
| private static final Logger logger = LoggerFactory.getLogger(OperatorCreatorRegistry.class); |
| |
| private volatile Map<Class<?>, Constructor<?>> constructorRegistry = new HashMap<Class<?>, Constructor<?>>(); |
| private volatile Map<Class<?>, Object> instanceRegistry = new HashMap<Class<?>, Object>(); |
| |
| public OperatorCreatorRegistry(ScanResult scanResult) { |
| addImplementorsToMap(scanResult, BatchCreator.class); |
| addImplementorsToMap(scanResult, RootCreator.class); |
| logger.debug("Adding Operator Creator map: {}", constructorRegistry); |
| } |
| |
| public synchronized Object getOperatorCreator(Class<?> operator) throws ExecutionSetupException { |
| Object opCreator = instanceRegistry.get(operator); |
| if (opCreator != null) { |
| return opCreator; |
| } |
| |
| Constructor<?> c = constructorRegistry.get(operator); |
| if(c == null) { |
| throw new ExecutionSetupException( |
| String.format("Failure finding OperatorCreator constructor for config %s", operator.getCanonicalName())); |
| } |
| try { |
| opCreator = c.newInstance(); |
| instanceRegistry.put(operator, opCreator); |
| return opCreator; |
| } catch (Throwable t) { |
| throw ExecutionSetupException.fromThrowable( |
| String.format("Failure creating OperatorCreator for Operator %s", operator.getCanonicalName()), t); |
| } |
| } |
| |
| private <T> void addImplementorsToMap(ScanResult scanResult, Class<T> baseInterface) { |
| Set<Class<? extends T>> providerClasses = scanResult.getImplementations(baseInterface); |
| for (Class<?> c : providerClasses) { |
| Class<?> operatorClass = c; |
| boolean interfaceFound = false; |
| while (!interfaceFound && !(c.equals(java.lang.Object.class))) { |
| Type[] ifaces = c.getGenericInterfaces(); // never returns null |
| for (Type iface : ifaces) { |
| if (!(iface instanceof ParameterizedType |
| && ((ParameterizedType)iface).getRawType().equals(baseInterface))) { |
| continue; |
| } |
| Type[] args = ((ParameterizedType)iface).getActualTypeArguments(); |
| interfaceFound = true; |
| boolean constructorFound = false; |
| for (Constructor<?> constructor : operatorClass.getConstructors()) { |
| Class<?>[] params = constructor.getParameterTypes(); |
| if (params.length == 0) { |
| Constructor<?> old = constructorRegistry.put((Class<?>) args[0], constructor); |
| if (old != null) { |
| throw new RuntimeException( |
| String.format("Duplicate OperatorCreator [%s, %s] found for PhysicalOperator %s", |
| old.getDeclaringClass().getCanonicalName(), operatorClass.getCanonicalName(), |
| ((Class<?>) args[0]).getCanonicalName())); |
| } |
| constructorFound = true; |
| } |
| } |
| if (!constructorFound) { |
| logger.debug("Skipping registration of OperatorCreator {} as it doesn't have a default constructor", |
| operatorClass.getCanonicalName()); |
| } |
| } |
| c = c.getSuperclass(); |
| } |
| } |
| } |
| } |