| /* |
| * Copyright (C) 2018 Seoul National University |
| * |
| * Licensed 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.nemo.runtime.common.state; |
| |
| import org.apache.nemo.common.StateMachine; |
| |
| /** |
| * Represents the states and their transitions of a stage. |
| * |
| * Maintained as simple two (INCOMPLETE, COMPLETE) states to avoid ambiguity when the tasks are in different states. |
| * For example it is not clear whether a stage should be EXECUTING or SHOULD_RESTART, if one of the tasks in the stage |
| * is EXECUTING, and another is SHOULD_RESTART. |
| */ |
| public final class StageState { |
| private final StateMachine stateMachine; |
| |
| public StageState() { |
| stateMachine = buildTaskStateMachine(); |
| } |
| |
| private StateMachine buildTaskStateMachine() { |
| final StateMachine.Builder stateMachineBuilder = StateMachine.newBuilder(); |
| |
| // Add states |
| stateMachineBuilder.addState(State.INCOMPLETE, "Some tasks in this stage are not complete."); |
| stateMachineBuilder.addState(State.COMPLETE, "All of this stage's tasks have completed."); |
| |
| // Add transitions |
| stateMachineBuilder.addTransition( |
| State.INCOMPLETE, State.INCOMPLETE, "A task in the stage needs to be retried"); |
| stateMachineBuilder.addTransition(State.INCOMPLETE, State.COMPLETE, "All tasks complete"); |
| stateMachineBuilder.addTransition(State.COMPLETE, State.INCOMPLETE, |
| "Completed before, but a task in this stage should be retried"); |
| stateMachineBuilder.addTransition(State.COMPLETE, State.COMPLETE, |
| "Completed before, but probably a cloned task has completed again"); |
| |
| stateMachineBuilder.setInitialState(State.INCOMPLETE); |
| |
| return stateMachineBuilder.build(); |
| } |
| |
| public StateMachine getStateMachine() { |
| return stateMachine; |
| } |
| |
| /** |
| * StageState. |
| */ |
| public enum State { |
| INCOMPLETE, |
| COMPLETE |
| } |
| |
| @Override |
| public String toString() { |
| final StringBuffer sb = new StringBuffer(); |
| sb.append(stateMachine.getCurrentState()); |
| return sb.toString(); |
| } |
| } |