| 1 | /* |
| 2 | * Copyright 2006-2007 the original author or authors. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | package org.springframework.batch.core.partition.support; |
| 18 | |
| 19 | import java.util.Collection; |
| 20 | |
| 21 | import org.springframework.batch.core.BatchStatus; |
| 22 | import org.springframework.batch.core.JobExecutionException; |
| 23 | import org.springframework.batch.core.Step; |
| 24 | import org.springframework.batch.core.StepExecution; |
| 25 | import org.springframework.batch.core.partition.PartitionHandler; |
| 26 | import org.springframework.batch.core.partition.StepExecutionSplitter; |
| 27 | import org.springframework.batch.core.step.AbstractStep; |
| 28 | import org.springframework.batch.item.ExecutionContext; |
| 29 | import org.springframework.util.Assert; |
| 30 | |
| 31 | /** |
| 32 | * Implementation of {@link Step} which partitions the execution and spreads the |
| 33 | * load using a {@link PartitionHandler}. |
| 34 | * |
| 35 | * @author Dave Syer |
| 36 | * @since 2.0 |
| 37 | */ |
| 38 | public class PartitionStep extends AbstractStep { |
| 39 | |
| 40 | private StepExecutionSplitter stepExecutionSplitter; |
| 41 | |
| 42 | private PartitionHandler partitionHandler; |
| 43 | |
| 44 | private StepExecutionAggregator aggregator = new StepExecutionAggregator(); |
| 45 | |
| 46 | /** |
| 47 | * Public setter for mandatory property {@link PartitionHandler}. |
| 48 | * @param partitionHandler the {@link PartitionHandler} to set |
| 49 | */ |
| 50 | public void setPartitionHandler(PartitionHandler partitionHandler) { |
| 51 | this.partitionHandler = partitionHandler; |
| 52 | } |
| 53 | |
| 54 | /** |
| 55 | * Public setter for mandatory property {@link StepExecutionSplitter}. |
| 56 | * @param stepExecutionSplitter the {@link StepExecutionSplitter} to set |
| 57 | */ |
| 58 | public void setStepExecutionSplitter(StepExecutionSplitter stepExecutionSplitter) { |
| 59 | this.stepExecutionSplitter = stepExecutionSplitter; |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * Assert that mandatory properties are set (stepExecutionSplitter, |
| 64 | * partitionHandler) and delegate top superclass. |
| 65 | * |
| 66 | * @see AbstractStep#afterPropertiesSet() |
| 67 | */ |
| 68 | public void afterPropertiesSet() throws Exception { |
| 69 | Assert.notNull(stepExecutionSplitter, "StepExecutionSplitter must be provided"); |
| 70 | Assert.notNull(partitionHandler, "PartitionHandler must be provided"); |
| 71 | super.afterPropertiesSet(); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Delegate execution to the {@link PartitionHandler} provided. The |
| 76 | * {@link StepExecution} passed in here becomes the parent or master |
| 77 | * execution for the partition, summarising the status on exit of the |
| 78 | * logical grouping of work carried out by the {@link PartitionHandler}. The |
| 79 | * individual step executions and their input parameters (through |
| 80 | * {@link ExecutionContext}) for the partition elements are provided by the |
| 81 | * {@link StepExecutionSplitter}. |
| 82 | * |
| 83 | * @param stepExecution the master step execution for the partition |
| 84 | * |
| 85 | * @see Step#execute(StepExecution) |
| 86 | */ |
| 87 | @Override |
| 88 | protected void doExecute(StepExecution stepExecution) throws Exception { |
| 89 | |
| 90 | // Wait for task completion and then aggregate the results |
| 91 | Collection<StepExecution> executions = partitionHandler.handle(stepExecutionSplitter, stepExecution); |
| 92 | stepExecution.upgradeStatus(BatchStatus.COMPLETED); |
| 93 | aggregator.aggregate(stepExecution, executions); |
| 94 | |
| 95 | // If anything failed or had a problem we need to crap out |
| 96 | if (stepExecution.getStatus().isUnsuccessful()) { |
| 97 | throw new JobExecutionException("Partition handler returned an unsuccessful step"); |
| 98 | } |
| 99 | |
| 100 | } |
| 101 | |
| 102 | } |