Java tutorial
/** * 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.hadoop.yarn.api.records; import java.nio.ByteBuffer; import java.util.List; import java.util.Map; import org.apache.hadoop.classification.InterfaceAudience.Public; import org.apache.hadoop.classification.InterfaceStability.Stable; import org.apache.hadoop.classification.InterfaceStability.Unstable; import org.apache.hadoop.yarn.api.ContainerManagementProtocol; import org.apache.hadoop.yarn.server.api.ApplicationInitializationContext; import org.apache.hadoop.yarn.server.api.AuxiliaryService; import org.apache.hadoop.yarn.util.Records; /** * {@code ContainerLaunchContext} represents all of the information * needed by the {@code NodeManager} to launch a container. * <p> * It includes details such as: * <ul> * <li>{@link ContainerId} of the container.</li> * <li>{@link Resource} allocated to the container.</li> * <li>User to whom the container is allocated.</li> * <li>Security tokens (if security is enabled).</li> * <li> * {@link LocalResource} necessary for running the container such * as binaries, jar, shared-objects, side-files etc. * </li> * <li>Optional, application-specific binary service data.</li> * <li>Environment variables for the launched process.</li> * <li>Command to launch the container.</li> * <li>Retry strategy when container exits with failure.</li> * </ul> * * @see ContainerManagementProtocol#startContainers(org.apache.hadoop.yarn.api.protocolrecords.StartContainersRequest) */ @Public @Stable public abstract class ContainerLaunchContext { @Public @Stable public static ContainerLaunchContext newInstance(Map<String, LocalResource> localResources, Map<String, String> environment, List<String> commands, Map<String, ByteBuffer> serviceData, ByteBuffer tokens, Map<ApplicationAccessType, String> acls) { return newInstance(localResources, environment, commands, serviceData, tokens, acls, null); } @Public @Unstable public static ContainerLaunchContext newInstance(Map<String, LocalResource> localResources, Map<String, String> environment, List<String> commands, Map<String, ByteBuffer> serviceData, ByteBuffer tokens, Map<ApplicationAccessType, String> acls, ContainerRetryContext containerRetryContext) { ContainerLaunchContext container = Records.newRecord(ContainerLaunchContext.class); container.setLocalResources(localResources); container.setEnvironment(environment); container.setCommands(commands); container.setServiceData(serviceData); container.setTokens(tokens); container.setApplicationACLs(acls); container.setContainerRetryContext(containerRetryContext); return container; } /** * Get all the tokens needed by this container. It may include file-system * tokens, ApplicationMaster related tokens if this container is an * ApplicationMaster or framework level tokens needed by this container to * communicate to various services in a secure manner. * * @return tokens needed by this container. */ @Public @Stable public abstract ByteBuffer getTokens(); /** * Set security tokens needed by this container. * @param tokens security tokens */ @Public @Stable public abstract void setTokens(ByteBuffer tokens); /** * Get the configuration used by RM to renew tokens. * @return The configuration used by RM to renew the tokens. */ @Public @Unstable public abstract ByteBuffer getTokensConf(); /** * Set the configuration used by RM to renew the tokens. * @param tokensConf The configuration used by RM to renew the tokens */ @Public @Unstable public abstract void setTokensConf(ByteBuffer tokensConf); /** * Get <code>LocalResource</code> required by the container. * @return all <code>LocalResource</code> required by the container */ @Public @Stable public abstract Map<String, LocalResource> getLocalResources(); /** * Set <code>LocalResource</code> required by the container. All pre-existing * Map entries are cleared before adding the new Map * @param localResources <code>LocalResource</code> required by the container */ @Public @Stable public abstract void setLocalResources(Map<String, LocalResource> localResources); /** * <p> * Get application-specific binary <em>service data</em>. This is a map keyed * by the name of each {@link AuxiliaryService} that is configured on a * NodeManager and value correspond to the application specific data targeted * for the keyed {@link AuxiliaryService}. * </p> * * <p> * This will be used to initialize this application on the specific * {@link AuxiliaryService} running on the NodeManager by calling * {@link AuxiliaryService#initializeApplication(ApplicationInitializationContext)} * </p> * * @return application-specific binary <em>service data</em> */ @Public @Stable public abstract Map<String, ByteBuffer> getServiceData(); /** * <p> * Set application-specific binary <em>service data</em>. This is a map keyed * by the name of each {@link AuxiliaryService} that is configured on a * NodeManager and value correspond to the application specific data targeted * for the keyed {@link AuxiliaryService}. All pre-existing Map entries are * preserved. * </p> * * @param serviceData * application-specific binary <em>service data</em> */ @Public @Stable public abstract void setServiceData(Map<String, ByteBuffer> serviceData); /** * Get <em>environment variables</em> for the container. * @return <em>environment variables</em> for the container */ @Public @Stable public abstract Map<String, String> getEnvironment(); /** * Add <em>environment variables</em> for the container. All pre-existing Map * entries are cleared before adding the new Map * @param environment <em>environment variables</em> for the container */ @Public @Stable public abstract void setEnvironment(Map<String, String> environment); /** * Get the list of <em>commands</em> for launching the container. * @return the list of <em>commands</em> for launching the container */ @Public @Stable public abstract List<String> getCommands(); /** * Add the list of <em>commands</em> for launching the container. All * pre-existing List entries are cleared before adding the new List * @param commands the list of <em>commands</em> for launching the container */ @Public @Stable public abstract void setCommands(List<String> commands); /** * Get the <code>ApplicationACL</code>s for the application. * @return all the <code>ApplicationACL</code>s */ @Public @Stable public abstract Map<ApplicationAccessType, String> getApplicationACLs(); /** * Set the <code>ApplicationACL</code>s for the application. All pre-existing * Map entries are cleared before adding the new Map * @param acls <code>ApplicationACL</code>s for the application */ @Public @Stable public abstract void setApplicationACLs(Map<ApplicationAccessType, String> acls); /** * Get the <code>ContainerRetryContext</code> to relaunch container. * @return <code>ContainerRetryContext</code> to relaunch container. */ @Public @Unstable public abstract ContainerRetryContext getContainerRetryContext(); /** * Set the <code>ContainerRetryContext</code> to relaunch container. * @param containerRetryContext <code>ContainerRetryContext</code> to * relaunch container. */ @Public @Unstable public abstract void setContainerRetryContext(ContainerRetryContext containerRetryContext); }