| /* |
| * 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.samza.context; |
| |
| import java.io.Serializable; |
| import org.apache.samza.annotation.InterfaceStability; |
| import org.apache.samza.application.SamzaApplication; |
| import org.apache.samza.application.descriptors.ApplicationDescriptor; |
| |
| |
| /** |
| * The factory for creating {@link ApplicationTaskContext} instances for a {@link SamzaApplication}during task |
| * initialization. |
| * <p> |
| * Use {@link ApplicationDescriptor#withApplicationTaskContextFactory} to provide the |
| * {@link ApplicationTaskContextFactory}. Use {@link Context#getApplicationTaskContext()} to get the created |
| * {@link ApplicationTaskContext} instance for the current task. |
| * <p> |
| * The {@link ApplicationTaskContextFactory} implementation must be {@link Serializable}. |
| * |
| * @param <T> concrete type of {@link ApplicationTaskContext} created by this factory |
| */ |
| @InterfaceStability.Evolving |
| public interface ApplicationTaskContextFactory<T extends ApplicationTaskContext> extends Serializable { |
| /** |
| * Creates an instance of the application-defined {@link ApplicationTaskContext}. |
| * <p> |
| * Applications should implement this to provide a context for task initialization. |
| * |
| * @param externalContext external context provided for the application; null if it was not provided |
| * @param jobContext framework-provided job context |
| * @param containerContext framework-provided container context |
| * @param taskContext framework-provided task context |
| * @param applicationContainerContext application-defined container context; null if it was not provided |
| * @return a new instance of the application-defined {@link ApplicationTaskContext} |
| */ |
| default T create(ExternalContext externalContext, JobContext jobContext, ContainerContext containerContext, |
| TaskContext taskContext, ApplicationContainerContext applicationContainerContext) { |
| return create(jobContext, containerContext, taskContext, applicationContainerContext); |
| } |
| |
| /** |
| * New implementations should not implement this directly. Implement |
| * {@link #create(ExternalContext, JobContext, ContainerContext, TaskContext, ApplicationContainerContext)} instead. |
| * <p> |
| * This is the same as |
| * {@link #create(ExternalContext, JobContext, ContainerContext, TaskContext, ApplicationContainerContext)}, except it |
| * does not provide access to external context. |
| * <p> |
| * This is being left here for backwards compatibility. |
| * |
| * @param jobContext framework-provided job context |
| * @param containerContext framework-provided container context |
| * @param taskContext framework-provided task context |
| * @param applicationContainerContext application-defined container context; null if it was not provided |
| * @return a new instance of the application-defined {@link ApplicationTaskContext} |
| * |
| * Deprecated: Applications should implement |
| * {@link #create(ExternalContext, JobContext, ContainerContext, TaskContext, ApplicationContainerContext)} directly. |
| * This is being left here for backwards compatibility. |
| */ |
| @Deprecated |
| default T create(JobContext jobContext, ContainerContext containerContext, TaskContext taskContext, |
| ApplicationContainerContext applicationContainerContext) { |
| // adding this here so that new apps do not need to implement this |
| throw new UnsupportedOperationException("Please implement a version of create for the factory implementation."); |
| } |
| } |