| /* |
| * 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.twill.api; |
| |
| import org.apache.twill.common.Cancellable; |
| import org.apache.twill.discovery.DiscoveryServiceClient; |
| import org.apache.twill.discovery.ServiceDiscovered; |
| |
| import java.net.InetAddress; |
| import java.util.concurrent.locks.Lock; |
| |
| /** |
| * Represents the runtime context of a {@link TwillRunnable}. |
| */ |
| public interface TwillContext extends ServiceAnnouncer, DiscoveryServiceClient { |
| |
| /** |
| * Returns the {@link RunId} of this running instance of {@link TwillRunnable}. |
| */ |
| RunId getRunId(); |
| |
| /** |
| * Returns the {@link RunId} of this running application. |
| */ |
| RunId getApplicationRunId(); |
| |
| /** |
| * Returns the number of running instances assigned for this {@link TwillRunnable}. |
| */ |
| int getInstanceCount(); |
| |
| /** |
| * Returns the hostname that the runnable is running on. |
| */ |
| InetAddress getHost(); |
| |
| /** |
| * Returns the runtime arguments that are passed to the {@link TwillRunnable}. |
| */ |
| String[] getArguments(); |
| |
| /** |
| * Returns the runtime arguments that are passed to the {@link TwillApplication}. |
| */ |
| String[] getApplicationArguments(); |
| |
| /** |
| * Returns the {@link TwillRunnableSpecification} that was created by {@link TwillRunnable#configure()}. |
| */ |
| TwillRunnableSpecification getSpecification(); |
| |
| /** |
| * Returns an integer id from 0 to (instanceCount - 1). |
| */ |
| int getInstanceId(); |
| |
| /** |
| * Returns the number of virtual cores the runnable is allowed to use. |
| */ |
| int getVirtualCores(); |
| |
| /** |
| * Returns the amount of memory in MB the runnable is allowed to use. |
| */ |
| int getMaxMemoryMB(); |
| |
| /** |
| * Discover service with the given name that is announced within the same {@link TwillApplication}. |
| * |
| * @param name Name of the service |
| * @return A {@link ServiceDiscovered} object representing the result. |
| */ |
| @Override |
| ServiceDiscovered discover(String name); |
| |
| /** |
| * Register to participate in a leader election by instances within the same {@link TwillApplication}. |
| * |
| * @param name Unique name for the election |
| * @return A {@link org.apache.twill.common.Cancellable} object representing this candidate's participation. |
| */ |
| Cancellable electLeader(String name, ElectionHandler participantHandler); |
| |
| /** |
| * Creates a {@link Lock} for performing locking mechanism within the same {@link TwillApplication}. |
| * The lock created is a reentrant such that if the lock is owned by the current thread, it will return immediately. |
| * |
| * @param name Unique name for the lock |
| * @return A {@link Lock} object |
| */ |
| Lock createLock(String name); |
| } |