| /* |
| * 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.beam.runners.dataflow.worker; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.ServiceLoader; |
| import java.util.Set; |
| import org.apache.beam.sdk.util.common.ReflectHelpers; |
| import org.apache.beam.sdk.util.common.ReflectHelpers.ObjectsClassComparator; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.collect.ImmutableList; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.collect.Lists; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.collect.Sets; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * A {@link ContextActivationObserverRegistry} allows creating a {@link ContextActivationObserver}. |
| */ |
| public class ContextActivationObserverRegistry { |
| |
| static { |
| LoggerFactory.getLogger(ContextActivationObserverRegistry.class); |
| } |
| |
| private static final List<ContextActivationObserver> |
| REGISTERED_CONTEXT_ACTIVATION_OBSERVER_FACTORIES; |
| |
| static { |
| List<ContextActivationObserver> contextActivationObserversToRegister = new ArrayList<>(); |
| |
| // Enumerate all the ContextActivationObserver.Registrars, adding them to registry. |
| Set<ContextActivationObserver.Registrar> registrars = |
| Sets.newTreeSet(ObjectsClassComparator.INSTANCE); |
| registrars.addAll( |
| Lists.newArrayList( |
| ServiceLoader.load( |
| ContextActivationObserver.Registrar.class, ReflectHelpers.findClassLoader()))); |
| |
| for (ContextActivationObserver.Registrar registrar : registrars) { |
| if (registrar.isEnabled()) { |
| contextActivationObserversToRegister.add(registrar.getContextActivationObserver()); |
| } |
| } |
| |
| REGISTERED_CONTEXT_ACTIVATION_OBSERVER_FACTORIES = |
| ImmutableList.copyOf(contextActivationObserversToRegister); |
| } |
| |
| /** |
| * Creates a ContextActivationObserverRegistry containing registrations for all standard |
| * ContextActivationObservers part of the core Java Apache Beam SDK and also any registrations |
| * provided by {@link ContextActivationObserver.Registrar}s. |
| */ |
| public static ContextActivationObserverRegistry createDefault() { |
| return new ContextActivationObserverRegistry(); |
| } |
| |
| /** The list of {@link ContextActivationObserver}s. */ |
| private final List<ContextActivationObserver> contextActivationObservers; |
| |
| private ContextActivationObserverRegistry() { |
| contextActivationObservers = new ArrayList<>(REGISTERED_CONTEXT_ACTIVATION_OBSERVER_FACTORIES); |
| } |
| |
| /** Returns all {@link ContextActivationObserver}s registered with this registry. */ |
| public List<ContextActivationObserver> getContextActivationObservers() { |
| return contextActivationObservers; |
| } |
| } |