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/* * Copyright 2014 the original author or authors. * * 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.springframework.batch.core.jsr.job; import java.util.List; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.batch.core.BatchStatus; import org.springframework.batch.core.JobExecution; import org.springframework.batch.core.StartLimitExceededException; import org.springframework.batch.core.Step; import org.springframework.batch.core.StepExecution; import org.springframework.batch.core.explore.JobExplorer; import org.springframework.batch.core.job.SimpleStepHandler; import org.springframework.batch.core.repository.JobRepository; import org.springframework.batch.core.repository.JobRestartException; import org.springframework.batch.item.ExecutionContext; import org.springframework.util.Assert; import org.springframework.util.CollectionUtils; import org.springframework.util.StringUtils; /** * Extends {@link SimpleStepHandler} to apply JSR-352 specific logic for whether to * start a step. * * @author Michael Minella * @since 3.0 */ public class DefaultStepHandler extends SimpleStepHandler { private static final Log logger = LogFactory.getLog(DefaultStepHandler.class); private JobExplorer jobExplorer; /** * @param jobRepository */ public DefaultStepHandler(JobRepository jobRepository, JobExplorer jobExplorer) { super(jobRepository, new ExecutionContext()); this.jobExplorer = jobExplorer; } @Override public void afterPropertiesSet() throws Exception { super.afterPropertiesSet(); Assert.state(jobExplorer != null, "A JobExplorer must be provided"); } /** * Given a step and configuration, return true if the step should start, * false if it should not, and throw an exception if the job should finish. * @param lastStepExecution the last step execution * @param jobInstance * @param step * * @throws StartLimitExceededException if the start limit has been exceeded * for this step * @throws JobRestartException if the job is in an inconsistent state from * an earlier failure */ @Override protected boolean shouldStart(StepExecution lastStepExecution, JobExecution jobExecution, Step step) throws JobRestartException, StartLimitExceededException { BatchStatus stepStatus; String restartStep = null; if (lastStepExecution == null) { jobExecution.getExecutionContext().put("batch.startedStep", step.getName()); stepStatus = BatchStatus.STARTING; } else { stepStatus = lastStepExecution.getStatus(); JobExecution lastJobExecution = getLastJobExecution(jobExecution); if (lastJobExecution.getExecutionContext().containsKey("batch.restartStep")) { restartStep = lastJobExecution.getExecutionContext().getString("batch.restartStep"); if (CollectionUtils.isEmpty(jobExecution.getStepExecutions()) && lastJobExecution.getStatus() == BatchStatus.STOPPED && StringUtils.hasText(restartStep)) { if (!restartStep.equals(step.getName()) && !jobExecution.getExecutionContext().containsKey("batch.startedStep")) { logger.info("Job was stopped and should restart at step " + restartStep + ". The current step is " + step.getName()); return false; } else { // Indicates the starting point for execution evaluation per JSR-352 jobExecution.getExecutionContext().put("batch.startedStep", step.getName()); } } } } if (stepStatus == BatchStatus.UNKNOWN) { throw new JobRestartException("Cannot restart step from UNKNOWN status. " + "The last execution ended with a failure that could not be rolled back, " + "so it may be dangerous to proceed. Manual intervention is probably necessary."); } if ((stepStatus == BatchStatus.COMPLETED && step.isAllowStartIfComplete() == false) || stepStatus == BatchStatus.ABANDONED) { // step is complete, false should be returned, indicating that the // step should not be started logger.info("Step already complete or not restartable, so no action to execute: " + lastStepExecution); return false; } if (getJobRepository().getStepExecutionCount(jobExecution.getJobInstance(), step.getName()) < step .getStartLimit()) { // step start count is less than start max, return true return true; } else { // start max has been exceeded, throw an exception. throw new StartLimitExceededException("Maximum start limit exceeded for step: " + step.getName() + "StartMax: " + step.getStartLimit()); } } /** * Since all JSR-352 jobs are run asynchronously, {@link JobRepository#getLastJobExecution(String, org.springframework.batch.core.JobParameters)} * could return the currently running {@link JobExecution}. To get around this, we use the {@link JobExplorer} * to get a list of the executions and get the most recent one that is <em>not</em> the currently running * {@link JobExecution}. * * @param jobExecution * @return the last executed JobExecution. */ private JobExecution getLastJobExecution(JobExecution jobExecution) { List<JobExecution> jobExecutions = jobExplorer.getJobExecutions(jobExecution.getJobInstance()); JobExecution lastJobExecution = null; for (JobExecution curJobExecution : jobExecutions) { if (lastJobExecution == null && curJobExecution.getId().longValue() != jobExecution.getId().longValue()) { lastJobExecution = curJobExecution; } else if (curJobExecution.getId().longValue() != jobExecution.getId().longValue() && (lastJobExecution == null || curJobExecution.getId().longValue() > lastJobExecution.getId().longValue())) { lastJobExecution = curJobExecution; } } return lastJobExecution; } }