RESOLVED - issue BATCH-110: Potential simplification of DefaultJobExecutor by not having to include the StepExecutorFactory always

http://opensource.atlassian.com/projects/spring/browse/BATCH-110

execution/src/main/java/org/springframework/batch/execution/job/DefaultJobExecutor.java

@@ -33,13 +33,13 @@ import org.springframework.batch.core.executor.StepInterruptedException;
 import org.springframework.batch.core.repository.JobRepository;
 import org.springframework.batch.core.runtime.JobExecutionContext;
 import org.springframework.batch.core.runtime.StepExecutionContext;
-import org.springframework.batch.execution.step.DefaultStepExecutorFactory;
+import org.springframework.batch.execution.step.SimpleStepExecutorFactory;
 import org.springframework.batch.io.exception.BatchCriticalException;
 import org.springframework.batch.repeat.ExitStatus;
 import org.springframework.batch.repeat.RepeatContext;
 
 /**
- * Default implementation of (@JobLifecycle) interface. Sequentially executes a
+ * Default implementation of (@link JobExecutor} interface. Sequentially executes a
  * job by iterating it's life of steps. Interruption of a job run is pluggable
  * by passing in various interruption policies.
  * 
@@ -47,9 +47,11 @@ import org.springframework.batch.repeat.RepeatContext;
  */
 public class DefaultJobExecutor implements JobExecutor {
 
+	private static final SimpleStepExecutorFactory DEFAULT_STEP_EXECUTOR_FACTORY = new SimpleStepExecutorFactory();
+
 	private JobRepository jobRepository;
 
-	private StepExecutorFactory stepExecutorResolver = new DefaultStepExecutorFactory();
+	private StepExecutorFactory stepExecutorFactory = DEFAULT_STEP_EXECUTOR_FACTORY;
 
 	public ExitStatus run(JobConfiguration configuration, JobExecutionContext jobExecutionContext)
 			throws BatchCriticalException {
@@ -69,7 +71,7 @@ public class DefaultJobExecutor implements JobExecutor {
 				StepConfiguration stepConfiguration = (StepConfiguration) j.next();
 				if (shouldStart(step, stepConfiguration)) {
 					updateStatus(jobExecutionContext, BatchStatus.STARTED);
-					StepExecutor stepExecutor = stepExecutorResolver.getExecutor(stepConfiguration);
+					StepExecutor stepExecutor = stepExecutorFactory.getExecutor(stepConfiguration);
 					StepExecutionContext stepExecutionContext = new StepExecutionContext(jobExecutionContext, step);
 					status = stepExecutor.process(stepConfiguration, stepExecutionContext);
 				}
@@ -145,10 +147,11 @@ public class DefaultJobExecutor implements JobExecutor {
 
 	public void setJobRepository(JobRepository jobRepository) {
 		this.jobRepository = jobRepository;
+		DEFAULT_STEP_EXECUTOR_FACTORY.setJobRepository(jobRepository);
 	}
 
-	public void setStepExecutorResolver(StepExecutorFactory stepExecutorResolver) {
-		this.stepExecutorResolver = stepExecutorResolver;
+	public void setStepExecutorFactory(StepExecutorFactory stepExecutorResolver) {
+		this.stepExecutorFactory = stepExecutorResolver;
 	}
 
 }

execution/src/main/java/org/springframework/batch/execution/step/SimpleStepExecutorFactory.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2006-2007 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.execution.step;
+
+import org.springframework.batch.core.configuration.StepConfiguration;
+import org.springframework.batch.core.executor.StepExecutor;
+import org.springframework.batch.core.executor.StepExecutorFactory;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.execution.step.simple.SimpleStepConfiguration;
+import org.springframework.batch.execution.step.simple.SimpleStepExecutor;
+import org.springframework.batch.repeat.RepeatOperations;
+import org.springframework.batch.repeat.policy.SimpleCompletionPolicy;
+import org.springframework.batch.repeat.support.RepeatTemplate;
+import org.springframework.util.Assert;
+
+/**
+ * A {@link StepExecutorFactory} that only knows how to create
+ * {@link SimpleStepExecutor} instances.
+ * 
+ * @author Dave Syer
+ * 
+ */
+public class SimpleStepExecutorFactory implements StepExecutorFactory {
+
+	private JobRepository jobRepository;
+
+	/**
+	 * Create a {@link SimpleStepExecutor} for this configuration. If the
+	 * configuration is a {@link SimpleStepConfiguration} then a
+	 * {@link StepExecutor} is created with policies matching the commit
+	 * interval of the configuration. <br/>
+	 * 
+	 * @throws IllegalStateException
+	 *             if the configuration is not a {@link SimpleStepConfiguration}.
+	 * @throws IllegalStateException
+	 *             if the {@link JobRepository} is null.
+	 * 
+	 * @see StepExecutorFactory#getExecutor(StepConfiguration)
+	 */
+	public StepExecutor getExecutor(StepConfiguration configuration) {
+
+		Assert.notNull(jobRepository, "JobRepository cannot be null");
+		Assert.state(configuration instanceof SimpleStepConfiguration,
+				"StepConfiguration must be instance of SimpleStepConfiguration - found: ["
+						+ (configuration == null ? null : configuration
+								.getClass()) + "]");
+
+		SimpleStepExecutor executor = new SimpleStepExecutor();
+		executor.setRepository(jobRepository);
+		RepeatTemplate template = new RepeatTemplate();
+		RepeatOperations repeatOperations = template;
+		template.setCompletionPolicy(new SimpleCompletionPolicy(
+				((SimpleStepConfiguration) configuration).getCommitInterval()));
+
+		executor.setChunkOperations(repeatOperations);
+
+		return executor;
+
+	}
+
+	public void setJobRepository(JobRepository jobRepository) {
+		this.jobRepository = jobRepository;
+	}
+
+}