| 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.job; |
| 18 | |
| 19 | import java.util.Date; |
| 20 | import java.util.Iterator; |
| 21 | import java.util.List; |
| 22 | |
| 23 | import org.springframework.batch.core.BatchStatus; |
| 24 | import org.springframework.batch.core.JobExecution; |
| 25 | import org.springframework.batch.core.JobExecutionException; |
| 26 | import org.springframework.batch.core.JobInstance; |
| 27 | import org.springframework.batch.core.JobInterruptedException; |
| 28 | import org.springframework.batch.core.StartLimitExceededException; |
| 29 | import org.springframework.batch.core.Step; |
| 30 | import org.springframework.batch.core.StepExecution; |
| 31 | import org.springframework.batch.core.UnexpectedJobExecutionException; |
| 32 | import org.springframework.batch.item.ExecutionContext; |
| 33 | import org.springframework.batch.repeat.ExitStatus; |
| 34 | |
| 35 | /** |
| 36 | * Simple implementation of (@link Job} interface providing the ability to run a |
| 37 | * {@link JobExecution}. Sequentially executes a job by iterating through its |
| 38 | * list of steps. |
| 39 | * |
| 40 | * @author Lucas Ward |
| 41 | * @author Dave Syer |
| 42 | */ |
| 43 | public class SimpleJob extends AbstractJob { |
| 44 | |
| 45 | /** |
| 46 | * Run the specified job by looping through the steps and delegating to the |
| 47 | * {@link Step}. |
| 48 | * |
| 49 | * @see org.springframework.batch.core.Job#execute(org.springframework.batch.core.JobExecution) |
| 50 | * @throws StartLimitExceededException if start limit of one of the steps |
| 51 | * was exceeded |
| 52 | */ |
| 53 | public void execute(JobExecution execution) throws JobExecutionException { |
| 54 | |
| 55 | JobInstance jobInstance = execution.getJobInstance(); |
| 56 | |
| 57 | StepExecution currentStepExecution = null; |
| 58 | int startedCount = 0; |
| 59 | List steps = getSteps(); |
| 60 | |
| 61 | // holder for potential job failure to be passed to onError listener |
| 62 | Throwable jobFailure = null; |
| 63 | |
| 64 | try { |
| 65 | |
| 66 | // The job was already stopped before we even got this far. Deal |
| 67 | // with it in the same way as any other interruption. |
| 68 | if (execution.getStatus() == BatchStatus.STOPPING) { |
| 69 | throw new JobInterruptedException("JobExecution already stopped before being executed."); |
| 70 | } |
| 71 | |
| 72 | execution.setStartTime(new Date()); |
| 73 | updateStatus(execution, BatchStatus.STARTING); |
| 74 | |
| 75 | getCompositeListener().beforeJob(execution); |
| 76 | |
| 77 | for (Iterator i = steps.iterator(); i.hasNext();) { |
| 78 | |
| 79 | if (execution.getStatus() == BatchStatus.STOPPING) { |
| 80 | throw new JobInterruptedException("JobExecution interrupted."); |
| 81 | } |
| 82 | |
| 83 | Step step = (Step) i.next(); |
| 84 | |
| 85 | if (shouldStart(jobInstance, step)) { |
| 86 | |
| 87 | startedCount++; |
| 88 | updateStatus(execution, BatchStatus.STARTED); |
| 89 | currentStepExecution = execution.createStepExecution(step); |
| 90 | |
| 91 | StepExecution lastStepExecution = getJobRepository().getLastStepExecution(jobInstance, step); |
| 92 | |
| 93 | boolean isRestart = (lastStepExecution != null && !lastStepExecution.getStatus().equals( |
| 94 | BatchStatus.COMPLETED)) ? true : false; |
| 95 | |
| 96 | if (isRestart) { |
| 97 | currentStepExecution.setExecutionContext(lastStepExecution.getExecutionContext()); |
| 98 | } |
| 99 | else { |
| 100 | currentStepExecution.setExecutionContext(new ExecutionContext()); |
| 101 | } |
| 102 | |
| 103 | step.execute(currentStepExecution); |
| 104 | |
| 105 | } |
| 106 | } |
| 107 | |
| 108 | // Need to check again for stopped job |
| 109 | if (execution.getStatus() == BatchStatus.STOPPING) { |
| 110 | throw new JobInterruptedException("JobExecution interrupted."); |
| 111 | } |
| 112 | |
| 113 | updateStatus(execution, BatchStatus.COMPLETED); |
| 114 | |
| 115 | } |
| 116 | catch (JobInterruptedException e) { |
| 117 | execution.setStatus(BatchStatus.STOPPED); |
| 118 | rethrow(e); |
| 119 | } |
| 120 | catch (Throwable t) { |
| 121 | execution.setStatus(BatchStatus.FAILED); |
| 122 | jobFailure = t; |
| 123 | rethrow(t); |
| 124 | } |
| 125 | finally { |
| 126 | ExitStatus status = ExitStatus.FAILED; |
| 127 | if (startedCount == 0) { |
| 128 | if (steps.size() > 0) { |
| 129 | status = ExitStatus.NOOP |
| 130 | .addExitDescription("All steps already completed. No processing was done."); |
| 131 | } |
| 132 | else { |
| 133 | status = ExitStatus.NOOP.addExitDescription("No steps configured for this job."); |
| 134 | } |
| 135 | } |
| 136 | else if (currentStepExecution != null) { |
| 137 | status = currentStepExecution.getExitStatus(); |
| 138 | } |
| 139 | execution.setExitStatus(status); |
| 140 | |
| 141 | BatchStatus jobStatus = execution.getStatus(); |
| 142 | if (jobStatus == BatchStatus.COMPLETED) { |
| 143 | getCompositeListener().afterJob(execution); |
| 144 | } |
| 145 | else if (jobStatus == BatchStatus.FAILED) { |
| 146 | getCompositeListener().onError(execution, jobFailure); |
| 147 | } |
| 148 | else if (jobStatus == BatchStatus.STOPPED) { |
| 149 | getCompositeListener().onInterrupt(execution); |
| 150 | } |
| 151 | |
| 152 | execution.setEndTime(new Date()); |
| 153 | getJobRepository().saveOrUpdate(execution); |
| 154 | } |
| 155 | |
| 156 | } |
| 157 | |
| 158 | private void updateStatus(JobExecution jobExecution, BatchStatus status) { |
| 159 | jobExecution.setStatus(status); |
| 160 | getJobRepository().saveOrUpdate(jobExecution); |
| 161 | } |
| 162 | |
| 163 | /* |
| 164 | * Given a step and configuration, return true if the step should start, |
| 165 | * false if it should not, and throw an exception if the job should finish. |
| 166 | */ |
| 167 | private boolean shouldStart(JobInstance jobInstance, Step step) throws JobExecutionException { |
| 168 | |
| 169 | BatchStatus stepStatus; |
| 170 | // if the last execution is null, the step has never been executed. |
| 171 | StepExecution lastStepExecution = getJobRepository().getLastStepExecution(jobInstance, step); |
| 172 | if (lastStepExecution == null) { |
| 173 | stepStatus = BatchStatus.STARTING; |
| 174 | } |
| 175 | else { |
| 176 | stepStatus = lastStepExecution.getStatus(); |
| 177 | } |
| 178 | |
| 179 | if (stepStatus == BatchStatus.UNKNOWN) { |
| 180 | throw new JobExecutionException("Cannot restart step from UNKNOWN status. " |
| 181 | + "The last execution ended with a failure that could not be rolled back, " |
| 182 | + "so it may be dangerous to proceed. " + "Manual intervention is probably necessary."); |
| 183 | } |
| 184 | |
| 185 | if (stepStatus == BatchStatus.COMPLETED && step.isAllowStartIfComplete() == false) { |
| 186 | // step is complete, false should be returned, indicating that the |
| 187 | // step should not be started |
| 188 | return false; |
| 189 | } |
| 190 | |
| 191 | if (getJobRepository().getStepExecutionCount(jobInstance, step) < step.getStartLimit()) { |
| 192 | // step start count is less than start max, return true |
| 193 | return true; |
| 194 | } |
| 195 | else { |
| 196 | // start max has been exceeded, throw an exception. |
| 197 | throw new StartLimitExceededException("Maximum start limit exceeded for step: " + step.getName() |
| 198 | + "StartMax: " + step.getStartLimit()); |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | /** |
| 203 | * @param t |
| 204 | */ |
| 205 | private static void rethrow(Throwable t) throws RuntimeException { |
| 206 | if (t instanceof RuntimeException) { |
| 207 | throw (RuntimeException) t; |
| 208 | } |
| 209 | else if (t instanceof Error) { |
| 210 | throw (Error) t; |
| 211 | } |
| 212 | else { |
| 213 | throw new UnexpectedJobExecutionException("Unexpected checked exception in job execution", t); |
| 214 | } |
| 215 | } |
| 216 | } |