| /** |
| * 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.server.resourcemanager.placement; |
| |
| /** |
| * This class implements the fallback logic for MappingRuleActions, this can |
| * be extended to implement the actual logic of the actions, this should be |
| * a base class for most actions. |
| */ |
| public abstract class MappingRuleActionBase implements MappingRuleAction { |
| /** |
| * The default fallback method is reject, so if the action fails |
| * We will reject the application. However this behaviour can be overridden |
| * on a per rule basis |
| */ |
| private MappingRuleResult fallback = MappingRuleResult.createRejectResult(); |
| |
| /** |
| * Returns the fallback action to be taken if the main action (result returned |
| * by the execute method) fails. |
| * e.g. Target queue does not exist, or reference is ambiguous |
| * @return The fallback action to be taken if the main action fails |
| */ |
| public MappingRuleResult getFallback() { |
| return fallback; |
| } |
| |
| /** |
| * Sets the fallback method to reject, if the action cannot be executed the |
| * application will get rejected. |
| * @return MappingRuleAction The same object for method chaining. |
| */ |
| public MappingRuleAction setFallbackReject() { |
| fallback = MappingRuleResult.createRejectResult(); |
| return this; |
| } |
| |
| /** |
| * Sets the fallback method to skip, if the action cannot be executed |
| * We move onto the next rule, ignoring this one. |
| * @return MappingRuleAction The same object for method chaining. |
| */ |
| public MappingRuleAction setFallbackSkip() { |
| fallback = MappingRuleResult.createSkipResult(); |
| return this; |
| } |
| |
| /** |
| * Sets the fallback method to place to default, if the action cannot be |
| * executed the application will be placed into the default queue, if the |
| * default queue does not exist the application will get rejected. |
| * @return MappingRuleAction The same object for method chaining. |
| */ |
| public MappingRuleAction setFallbackDefaultPlacement() { |
| fallback = MappingRuleResult.createDefaultPlacementResult(); |
| return this; |
| } |
| |
| /** |
| * This method is the main logic of the action, it shall determine based on |
| * the mapping context, what should be the action's result. |
| * @param variables The variable context, which contains all the variables |
| * @return The result of the action |
| */ |
| public abstract MappingRuleResult execute(VariableContext variables); |
| } |