/*
* Copyright 2006-2014 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.job;
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.JobInstance;
import org.springframework.batch.core.JobInterruptedException;
import org.springframework.batch.core.StartLimitExceededException;
import org.springframework.batch.core.Step;
import org.springframework.batch.core.StepExecution;
import org.springframework.batch.core.repository.JobRepository;
import org.springframework.batch.core.repository.JobRestartException;
import org.springframework.batch.item.ExecutionContext;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.util.Assert;
/**
* Implementation of {@link StepHandler} that manages repository and restart
* concerns.
*
* @author Dave Syer
*
*/
public class SimpleStepHandler implements StepHandler, InitializingBean {
private static final Log logger = LogFactory.getLog(SimpleStepHandler.class);
private JobRepository jobRepository;
private ExecutionContext executionContext;
/**
* Convenient default constructor for configuration usage.
*/
public SimpleStepHandler() {
this(null);
}
/**
* @param jobRepository a {@link org.springframework.batch.core.repository.JobRepository}
*/
public SimpleStepHandler(JobRepository jobRepository) {
this(jobRepository, new ExecutionContext());
}
/**
* @param jobRepository a {@link org.springframework.batch.core.repository.JobRepository}
* @param executionContext the {@link org.springframework.batch.item.ExecutionContext} for the current Step
*/
public SimpleStepHandler(JobRepository jobRepository, ExecutionContext executionContext) {
this.jobRepository = jobRepository;
this.executionContext = executionContext;
}
/**
* Check mandatory properties (jobRepository).
*
* @see InitializingBean#afterPropertiesSet()
*/
@Override
public void afterPropertiesSet() throws Exception {
Assert.state(jobRepository != null, "A JobRepository must be provided");
}
/**
* @return the used jobRepository
*/
protected JobRepository getJobRepository() {
return this.jobRepository;
}
/**
* @param jobRepository the jobRepository to set
*/
public void setJobRepository(JobRepository jobRepository) {
this.jobRepository = jobRepository;
}
/**
* A context containing values to be added to the step execution before it
* is handled.
*
* @param executionContext the execution context to set
*/
public void setExecutionContext(ExecutionContext executionContext) {
this.executionContext = executionContext;
}
@Override
public StepExecution handleStep(Step step, JobExecution execution) throws JobInterruptedException,
JobRestartException, StartLimitExceededException {
if (execution.isStopping()) {
throw new JobInterruptedException("JobExecution interrupted.");
}
JobInstance jobInstance = execution.getJobInstance();
StepExecution lastStepExecution = jobRepository.getLastStepExecution(jobInstance, step.getName());
if (stepExecutionPartOfExistingJobExecution(execution, lastStepExecution)) {
// If the last execution of this step was in the same job, it's
// probably intentional so we want to run it again...
logger.info(String.format("Duplicate step [%s] detected in execution of job=[%s]. "
+ "If either step fails, both will be executed again on restart.", step.getName(), jobInstance
.getJobName()));
lastStepExecution = null;
}
StepExecution currentStepExecution = lastStepExecution;
if (shouldStart(lastStepExecution, execution, step)) {
currentStepExecution = execution.createStepExecution(step.getName());
boolean isRestart = (lastStepExecution != null && !lastStepExecution.getStatus().equals(
BatchStatus.COMPLETED));
if (isRestart) {
currentStepExecution.setExecutionContext(lastStepExecution.getExecutionContext());
if(lastStepExecution.getExecutionContext().containsKey("batch.executed")) {
currentStepExecution.getExecutionContext().remove("batch.executed");
}
}
else {
currentStepExecution.setExecutionContext(new ExecutionContext(executionContext));
}
jobRepository.add(currentStepExecution);
logger.info("Executing step: [" + step.getName() + "]");
try {
step.execute(currentStepExecution);
currentStepExecution.getExecutionContext().put("batch.executed", true);
}
catch (JobInterruptedException e) {
// Ensure that the job gets the message that it is stopping
// and can pass it on to other steps that are executing
// concurrently.
execution.setStatus(BatchStatus.STOPPING);
throw e;
}
jobRepository.updateExecutionContext(execution);
if (currentStepExecution.getStatus() == BatchStatus.STOPPING
|| currentStepExecution.getStatus() == BatchStatus.STOPPED) {
// Ensure that the job gets the message that it is stopping
execution.setStatus(BatchStatus.STOPPING);
throw new JobInterruptedException("Job interrupted by step execution");
}
}
return currentStepExecution;
}
/**
* Detect whether a step execution belongs to this job execution.
* @param jobExecution the current job execution
* @param stepExecution an existing step execution
* @return true if the {@link org.springframework.batch.core.StepExecution} is part of the {@link org.springframework.batch.core.JobExecution}
*/
private boolean stepExecutionPartOfExistingJobExecution(JobExecution jobExecution, StepExecution stepExecution) {
return stepExecution != null && stepExecution.getJobExecutionId() != null
&& stepExecution.getJobExecutionId().equals(jobExecution.getId());
}
/**
* 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 jobExecution
* @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
*/
protected boolean shouldStart(StepExecution lastStepExecution, JobExecution jobExecution, Step step)
throws JobRestartException, StartLimitExceededException {
BatchStatus stepStatus;
if (lastStepExecution == null) {
stepStatus = BatchStatus.STARTING;
}
else {
stepStatus = lastStepExecution.getStatus();
}
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())
|| 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 (jobRepository.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());
}
}
}