IN PROGRESS - issue BATCH-384: consolidate map dao implementations

http://jira.springframework.org/browse/BATCH-384

MapJobDao split to MapJobInstanceDao and MapJobExecutionDao.
JobInstanceDao now has getJobInstance(Job,Params) rather than findJobInstances(Job,Params)

spring-batch-execution/src/main/java/org/springframework/batch/execution/repository/SimpleJobRepository.java

@@ -145,7 +145,6 @@ public class SimpleJobRepository implements JobRepository {
 		Assert.notNull(job, "Job must not be null.");
 		Assert.notNull(jobParameters, "JobParameters must not be null.");
 
-		List jobInstances = new ArrayList();
 		JobInstance jobInstance;
 
 		/*
@@ -157,15 +156,14 @@ public class SimpleJobRepository implements JobRepository {
 		 * has finished.
 		 */
 
-		jobInstances = jobInstanceDao.findJobInstances(job, jobParameters);
-		
-		if ((jobInstances.size() > 0) && (job.isRestartable() == false)) {
-			throw new BatchRestartException("JobInstance already exists and is not restartable");
-		}
+		jobInstance = jobInstanceDao.getJobInstance(job, jobParameters);
 
-		if (jobInstances.size() == 1) {
-			// One job was found
-			jobInstance = (JobInstance) jobInstances.get(0);
+		// existing job instance found
+		if (jobInstance != null) {
+			if (!job.isRestartable()) {
+				throw new BatchRestartException("JobInstance already exists and is not restartable");
+			}
+			
 			jobInstance.setJobExecutionCount(jobExecutionDao.getJobExecutionCount(jobInstance));
 			if (jobInstance.getJobExecutionCount() > job.getStartLimit()) {
 				throw new BatchRestartException("Restart Max exceeded for Job: " + jobInstance.toString());
@@ -190,15 +188,10 @@ public class SimpleJobRepository implements JobRepository {
 			}
 			jobInstance.setLastExecution(lastExecution);
 		}
-		else if (jobInstances.size() == 0) {
+		else {
 			// no job found, create one
 			jobInstance = jobInstanceDao.createJobInstance(job, jobParameters);
 		}
-		else {
-			// More than one job found, throw exception
-			throw new BatchRestartException("Error restarting job, more than one JobInstance found for: "
-					+ job.toString());
-		}
 
 		return generateJobExecution(jobInstance);
 

spring-batch-execution/src/main/java/org/springframework/batch/execution/repository/dao/JdbcJobInstanceDao.java

@@ -158,7 +158,7 @@ public class JdbcJobInstanceDao extends AbstractJdbcBatchMetadataDao implements
 	 * @throws IllegalArgumentException if any {@link JobIdentifier} fields are
 	 * null.
 	 */
-	public List findJobInstances(final Job job, final JobParameters jobParameters) {
+	public JobInstance getJobInstance(final Job job, final JobParameters jobParameters) {
 
 		Assert.notNull(job, "Job must not be null.");
 		Assert.hasLength(job.getName(), "Job must have a name");
@@ -172,8 +172,15 @@ public class JdbcJobInstanceDao extends AbstractJdbcBatchMetadataDao implements
 				return jobInstance;
 			}
 		};
-
-		return getJdbcTemplate().query(getQuery(FIND_JOBS), parameters, rowMapper);
+		
+		List instances = getJdbcTemplate().query(getQuery(FIND_JOBS), parameters, rowMapper);
+		
+		if (instances.isEmpty()) {
+			return null;
+		} else {
+			Assert.state(instances.size() == 1);
+			return (JobInstance) instances.get(0);
+		}
 	}
 
 	/**

spring-batch-execution/src/main/java/org/springframework/batch/execution/repository/dao/JobInstanceDao.java

@@ -37,6 +37,6 @@ public interface JobInstanceDao {
 	 * @return List of {@link JobInstance} objects matching
 	 * {@link JobIdentifier}
 	 */
-	List findJobInstances(Job job, JobParameters jobParameters);
+	JobInstance getJobInstance(Job job, JobParameters jobParameters);
 
 }

spring-batch-execution/src/main/java/org/springframework/batch/execution/repository/dao/MapJobDao.java

@@ -1,100 +0,0 @@
-/*
- * 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.repository.dao;
-
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
-import org.springframework.batch.core.domain.Job;
-import org.springframework.batch.core.domain.JobExecution;
-import org.springframework.batch.core.domain.JobInstance;
-import org.springframework.batch.core.domain.JobParameters;
-import org.springframework.batch.support.transaction.TransactionAwareProxyFactory;
-
-public class MapJobDao implements JobInstanceDao, JobExecutionDao {
-
-	private static Map jobsById;
-	private static Map executionsById;
-
-	private long currentId = 0;
-
-	static {
-		jobsById = TransactionAwareProxyFactory.createTransactionalMap();
-		executionsById = TransactionAwareProxyFactory.createTransactionalMap();
-	}
-	
-	public static void clear() {
-		jobsById.clear();
-		executionsById.clear();
-	}
-
-	public JobInstance createJobInstance(Job job, JobParameters jobParameters) {
-		JobInstance jobInstance = new JobInstance(new Long(currentId++), jobParameters, job);
-		
-		jobsById.put(jobInstance.getId(), jobInstance);
-		return jobInstance;
-	}
-
-	public List findJobInstances(Job job, JobParameters jobParameters) {
-		List list = new ArrayList();
-		for (Iterator iter = jobsById.values().iterator(); iter.hasNext();) {
-			JobInstance jobInstance = (JobInstance) iter.next();
-			if (jobInstance.getJobName().equals(job.getName()) && jobInstance.getJobParameters().equals(jobParameters)) {
-				list.add(jobInstance);
-			}
-		}
-		return list;
-	}
-
-	public int getJobExecutionCount(JobInstance jobInstance) {
-		Set executions = (Set) executionsById.get(jobInstance.getId());
-		if (executions==null) return 0;
-		return executions.size();	}
-
-	public void saveJobExecution(JobExecution jobExecution) {
-		Set executions = (Set) executionsById.get(jobExecution.getJobId());
-		if (executions==null) {
-			executions = TransactionAwareProxyFactory.createTransactionalSet();
-			executionsById.put(jobExecution.getJobId(), executions);
-		}
-		executions.add(jobExecution);
-		jobExecution.setId(new Long(currentId++));
-	}
-	
-	public List findJobExecutions(JobInstance jobInstance) {
-		Set executions = (Set) executionsById.get(jobInstance.getId());
-		if( executions == null ){
-			return new ArrayList();
-		}
-		else{
-			return new ArrayList(executions);
-		}
-	}
-
-	public void updateJobExecution(JobExecution jobExecution) {
-		// no-op
-	}
-
-	public JobExecution getLastJobExecution(JobInstance jobInstance) {
-		// no-op
-		return null;
-	}
-
-}

spring-batch-execution/src/main/java/org/springframework/batch/execution/repository/dao/MapJobExecutionDao.java

@@ -0,0 +1,58 @@
+package org.springframework.batch.execution.repository.dao;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.springframework.batch.core.domain.JobExecution;
+import org.springframework.batch.core.domain.JobInstance;
+import org.springframework.batch.support.transaction.TransactionAwareProxyFactory;
+import org.springframework.util.Assert;
+
+public class MapJobExecutionDao implements JobExecutionDao {
+
+	private static Map executionsByJobInstanceId = TransactionAwareProxyFactory.createTransactionalMap();
+
+	private static long currentId;
+
+	public static void clear() {
+		executionsByJobInstanceId.clear();
+	}
+
+	public int getJobExecutionCount(JobInstance jobInstance) {
+		Set executions = (Set) executionsByJobInstanceId.get(jobInstance.getId());
+		if (executions == null)
+			return 0;
+		return executions.size();
+	}
+
+	public void saveJobExecution(JobExecution jobExecution) {
+		Set executions = (Set) executionsByJobInstanceId.get(jobExecution.getJobId());
+		if (executions == null) {
+			executions = TransactionAwareProxyFactory.createTransactionalSet();
+			executionsByJobInstanceId.put(jobExecution.getJobId(), executions);
+		}
+		executions.add(jobExecution);
+		jobExecution.setId(new Long(currentId++));
+	}
+
+	public List findJobExecutions(JobInstance jobInstance) {
+		Set executions = (Set) executionsByJobInstanceId.get(jobInstance.getId());
+		if (executions == null) {
+			return new ArrayList();
+		}
+		else {
+			return new ArrayList(executions);
+		}
+	}
+
+	public void updateJobExecution(JobExecution jobExecution) {
+		Assert.notNull(jobExecution.getJobId());
+	}
+
+	public JobExecution getLastJobExecution(JobInstance jobInstance) {
+		Assert.notNull(jobInstance.getId());
+		return null;
+	}
+}

spring-batch-execution/src/main/java/org/springframework/batch/execution/repository/dao/MapJobInstanceDao.java

@@ -0,0 +1,45 @@
+package org.springframework.batch.execution.repository.dao;
+
+import java.util.Collection;
+import java.util.Iterator;
+
+import org.springframework.batch.core.domain.Job;
+import org.springframework.batch.core.domain.JobInstance;
+import org.springframework.batch.core.domain.JobParameters;
+import org.springframework.batch.support.transaction.TransactionAwareProxyFactory;
+
+public class MapJobInstanceDao implements JobInstanceDao {
+
+	private static Collection jobInstances = TransactionAwareProxyFactory.createTransactionalList();
+
+	private long currentId = 0;
+
+	public static void clear() {
+		jobInstances.clear();
+	}
+
+	public JobInstance createJobInstance(Job job, JobParameters jobParameters) {
+		
+		if (getJobInstance(job, jobParameters) != null) {
+			throw new IllegalArgumentException("JobInstance already exists for given job and parameters");
+		}
+		
+		JobInstance jobInstance = new JobInstance(new Long(currentId++), jobParameters, job);
+		jobInstances.add(jobInstance);
+		
+		return jobInstance;
+	}
+
+	public JobInstance getJobInstance(Job job, JobParameters jobParameters) {
+		
+		for (Iterator iterator = jobInstances.iterator(); iterator.hasNext();) {
+			JobInstance instance = (JobInstance) iterator.next();
+			if (instance.getJobName().equals(job.getName()) && instance.getJobParameters().equals(jobParameters)) {
+				return instance;
+			}
+		}
+		return null;
+		
+	}
+
+}

spring-batch-execution/src/test/java/org/springframework/batch/execution/job/SimpleJobTests.java

@@ -30,11 +30,11 @@ import org.springframework.batch.core.domain.Step;
 import org.springframework.batch.core.domain.StepExecution;
 import org.springframework.batch.core.repository.JobRepository;
 import org.springframework.batch.core.runtime.ExitStatusExceptionClassifier;
-import org.springframework.batch.execution.job.SimpleJob;
 import org.springframework.batch.execution.repository.SimpleJobRepository;
 import org.springframework.batch.execution.repository.dao.JobExecutionDao;
 import org.springframework.batch.execution.repository.dao.JobInstanceDao;
-import org.springframework.batch.execution.repository.dao.MapJobDao;
+import org.springframework.batch.execution.repository.dao.MapJobExecutionDao;
+import org.springframework.batch.execution.repository.dao.MapJobInstanceDao;
 import org.springframework.batch.execution.repository.dao.MapStepDao;
 import org.springframework.batch.execution.repository.dao.StepExecutionDao;
 import org.springframework.batch.execution.step.AbstractStep;
@@ -83,10 +83,11 @@ public class SimpleJobTests extends TestCase {
 	protected void setUp() throws Exception {
 		super.setUp();
 
-		MapJobDao.clear();
+		MapJobInstanceDao.clear();
+		MapJobExecutionDao.clear();
 		MapStepDao.clear();
-		jobInstanceDao = new MapJobDao();
-		jobExecutionDao = new MapJobDao();
+		jobInstanceDao = new MapJobInstanceDao();
+		jobExecutionDao = new MapJobExecutionDao();
 		stepExecutionDao = new MapStepDao();
 		jobRepository = new SimpleJobRepository(jobInstanceDao, jobExecutionDao, stepExecutionDao);
 		job = new SimpleJob();
@@ -255,7 +256,7 @@ public class SimpleJobTests extends TestCase {
 	 * Check JobRepository to ensure status is being saved.
 	 */
 	private void checkRepository(BatchStatus status, ExitStatus exitStatus) {
-		assertEquals(jobInstance, jobInstanceDao.findJobInstances(jobInstance.getJob(), jobParameters).get(0));
+		assertEquals(jobInstance, jobInstanceDao.getJobInstance(jobInstance.getJob(), jobParameters));
 		// because map dao stores in memory, it can be checked directly
 		JobExecution jobExecution = (JobExecution) jobExecutionDao.findJobExecutions(jobInstance).get(0);
 		assertEquals(jobInstance.getId(), jobExecution.getJobId());

spring-batch-execution/src/test/java/org/springframework/batch/execution/launch/SimpleJobTests.java

@@ -30,7 +30,8 @@ import org.springframework.batch.core.domain.JobInstance;
 import org.springframework.batch.core.domain.JobParameters;
 import org.springframework.batch.execution.job.SimpleJob;
 import org.springframework.batch.execution.repository.SimpleJobRepository;
-import org.springframework.batch.execution.repository.dao.MapJobDao;
+import org.springframework.batch.execution.repository.dao.MapJobExecutionDao;
+import org.springframework.batch.execution.repository.dao.MapJobInstanceDao;
 import org.springframework.batch.execution.repository.dao.MapStepDao;
 import org.springframework.batch.execution.step.AbstractStep;
 import org.springframework.batch.execution.step.ItemOrientedStep;
@@ -48,7 +49,7 @@ public class SimpleJobTests extends TestCase {
 
 	private List recovered = new ArrayList();
 
-	private SimpleJobRepository repository = new SimpleJobRepository(new MapJobDao(), new MapJobDao(), new MapStepDao());
+	private SimpleJobRepository repository = new SimpleJobRepository(new MapJobInstanceDao(), new MapJobExecutionDao(), new MapStepDao());
 
 	private List processed = new ArrayList();
 
@@ -65,7 +66,8 @@ public class SimpleJobTests extends TestCase {
 	protected void setUp() throws Exception {
 		super.setUp();
 		job.setJobRepository(repository);
-		MapJobDao.clear();
+		MapJobInstanceDao.clear();
+		MapJobExecutionDao.clear();
 		MapStepDao.clear();
 	}
 

spring-batch-execution/src/test/java/org/springframework/batch/execution/repository/SimpleJobRepositoryTests.java

@@ -226,36 +226,12 @@ public class SimpleJobRepositoryTests extends TestCase {
 ////		assertTrue(step.getStepExecutionCount() == 1);
 	}
 
-	// Test that a restartable job that has multiple instances throws an
-	// exception.
-	public void testFindRestartableJobWithMultipleInstances() throws Exception {
-
-		List jobs = new ArrayList();
-		jobs.add(databaseJob);
-		jobs.add(new JobInstance(new Long(127), jobParameters, jobConfiguration));
-		jobInstanceDao.findJobInstances(jobConfiguration, jobParameters);
-		jobInstanceDaoControl.setReturnValue(jobs);
-		jobInstanceDaoControl.replay();
-
-		try {
-			jobRepository.createJobExecution(jobConfiguration, jobParameters);
-			fail("Expected BatchRestartException");
-		}
-		catch (BatchRestartException e) {
-			// expected
-		}
-
-		jobInstanceDaoControl.verify();
-	}
-
 	public void testRestartJobStartLimitExceeded() throws Exception {
 
 		jobConfiguration.setStartLimit(1);
 
-		List jobs = new ArrayList();
-		jobInstanceDao.findJobInstances(jobConfiguration, jobParameters);
-		jobs.add(databaseJob);
-		jobInstanceDaoControl.setReturnValue(jobs);
+		jobInstanceDao.getJobInstance(jobConfiguration, jobParameters);
+		jobInstanceDaoControl.setReturnValue(databaseJob);
 		jobExecutionDao.getJobExecutionCount(databaseJob);
 		// return a greater execution count then the start limit, should throw
 		// exception

spring-batch-execution/src/test/java/org/springframework/batch/execution/repository/dao/AbstractJobDaoTests.java

@@ -99,23 +99,22 @@ public abstract class AbstractJobDaoTests extends AbstractTransactionalDataSourc
 
 	public void testFindNonExistentJob() {
 		// No job should be found since it hasn't been created.
-		List jobs = jobInstanceDao.findJobInstances(new JobSupport("nonexistentJob"), jobParameters);
-		assertTrue(jobs.size() == 0);
+		JobInstance jobInstance = jobInstanceDao.getJobInstance(new JobSupport("nonexistentJob"), jobParameters);
+		assertNull(jobInstance);
 	}
 
 	public void testFindJob() {
 
-		List jobs = jobInstanceDao.findJobInstances(job, jobParameters);
-		assertTrue(jobs.size() == 1);
-		JobInstance tempJob = (JobInstance) jobs.get(0);
-		assertTrue(jobInstance.equals(tempJob));
-		assertEquals(jobParameters, tempJob.getJobParameters());
+		JobInstance instance = jobInstanceDao.getJobInstance(job, jobParameters);
+		assertNotNull(instance);
+		assertTrue(jobInstance.equals(instance));
+		assertEquals(jobParameters, instance.getJobParameters());
 	}
 
 	public void testFindJobWithNullRuntime() {
 
 		try {
-			jobInstanceDao.findJobInstances(null, null);
+			jobInstanceDao.getJobInstance(null, null);
 			fail();
 		}
 		catch (IllegalArgumentException ex) {
@@ -137,14 +136,13 @@ public abstract class AbstractJobDaoTests extends AbstractTransactionalDataSourc
 		// JobInstance
 		JobParameters tempProps = new JobParametersBuilder().addString("job.key", "testKey1").toJobParameters();
 
-		List jobs;
-		jobs = jobInstanceDao.findJobInstances(scheduledJob, jobParameters);
-		assertEquals(1, jobs.size());
-		JobInstance jobInstance = (JobInstance) jobs.get(0);
-		assertEquals(jobParameters, jobInstance.getJobParameters());
+		JobInstance instance;
+		instance = jobInstanceDao.getJobInstance(scheduledJob, jobParameters);
+		assertNotNull(instance);
+		assertEquals(jobParameters, instance.getJobParameters());
 
-		jobs = jobInstanceDao.findJobInstances(scheduledJob, tempProps);
-		assertEquals(0, jobs.size());
+		instance = jobInstanceDao.getJobInstance(scheduledJob, tempProps);
+		assertNull(instance);
 
 	}
 
@@ -231,10 +229,10 @@ public abstract class AbstractJobDaoTests extends AbstractTransactionalDataSourc
 		// Create job.
 		jobInstance = jobInstanceDao.createJobInstance(testDefaultJob, jobParameters);
 
-		List jobs = jobInstanceDao.findJobInstances(testDefaultJob, jobParameters);
+		JobInstance instance = jobInstanceDao.getJobInstance(testDefaultJob, jobParameters);
 
-		assertEquals(1, jobs.size());
-		assertEquals(jobParameters.getString("job.key"), ((JobInstance) jobs.get(0)).getJobParameters().getString(
+		assertNotNull(instance);
+		assertEquals(jobParameters.getString("job.key"), instance.getJobParameters().getString(
 				"job.key"));
 
 	}

spring-batch-execution/src/test/java/org/springframework/batch/execution/repository/dao/MapJobDaoTests.java

@@ -1,81 +0,0 @@
-/*
- * 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.repository.dao;
-
-import java.util.List;
-
-import junit.framework.TestCase;
-
-import org.springframework.batch.core.domain.Job;
-import org.springframework.batch.core.domain.JobExecution;
-import org.springframework.batch.core.domain.JobInstance;
-import org.springframework.batch.core.domain.JobParameters;
-import org.springframework.batch.execution.job.JobSupport;
-
-public class MapJobDaoTests extends TestCase {
-
-	MapJobDao dao = new MapJobDao();
-	
-	JobParameters jobParameters = new JobParameters();
-	
-	Job fooJob = new JobSupport("foo");
-	
-	protected void setUp() throws Exception {
-		MapJobDao.clear();
-	}
-	
-	public void testCreateAndRetrieveSingle() throws Exception {
-		JobInstance job = dao.createJobInstance(fooJob, jobParameters);
-		List result = dao.findJobInstances(fooJob, jobParameters);
-		assertTrue(result.contains(job));
-	}
-	
-	public void testCreateAndRetrieveMultiple() throws Exception {
-		JobInstance job = dao.createJobInstance(fooJob, jobParameters);
-		Job barJob = new JobSupport("bar");
-		job = dao.createJobInstance(barJob, jobParameters);
-		List result = dao.findJobInstances(barJob, jobParameters);
-		assertEquals(1, result.size());
-		assertTrue(result.contains(job));		
-	}
-	
-	public void testNoExecutionsForNewJob() throws Exception {
-		JobInstance job = dao.createJobInstance(fooJob, jobParameters);
-		assertEquals(0, dao.getJobExecutionCount(job));
-	}
-
-	public void testSaveExecutionUpdatesId() throws Exception {
-		JobInstance job = dao.createJobInstance(fooJob, jobParameters);
-		JobExecution execution = new JobExecution(job);
-		assertNull(execution.getId());
-		dao.saveJobExecution(execution);
-		assertNotNull(execution.getId());
-	}
-	public void testCorrectExecutionCountForExistingJob() throws Exception {
-		JobInstance job = dao.createJobInstance(fooJob, jobParameters);
-		dao.saveJobExecution(new JobExecution(job));
-		assertEquals(1, dao.getJobExecutionCount(job));
-	}
-
-	public void testMultipleExecutionsPerExisting() throws Exception {
-		JobInstance job = dao.createJobInstance(fooJob, jobParameters);
-		dao.saveJobExecution(new JobExecution(job));
-		Thread.sleep(50L); // Hack, hack, hackety, hack - job executions are not unique if created too close together!
-		dao.saveJobExecution(new JobExecution(job));
-		assertEquals(2, dao.getJobExecutionCount(job));
-	}
-}

spring-batch-execution/src/test/java/org/springframework/batch/execution/repository/dao/MapJobExecutionDaoTests.java

@@ -0,0 +1,57 @@
+package org.springframework.batch.execution.repository.dao;
+
+import java.util.List;
+
+import junit.framework.TestCase;
+
+import org.springframework.batch.core.domain.JobExecution;
+import org.springframework.batch.core.domain.JobInstance;
+import org.springframework.batch.core.domain.JobParameters;
+import org.springframework.batch.execution.job.JobSupport;
+
+public class MapJobExecutionDaoTests extends TestCase {
+
+	JobExecutionDao dao = new MapJobExecutionDao();
+
+	JobInstance jobInstance = new JobInstance(new Long(1), new JobParameters(), new JobSupport("execTestJob"));
+
+	protected void setUp() throws Exception {
+		MapJobExecutionDao.clear();
+	}
+
+	/**
+	 * Save and find a job execution.
+	 */
+	public void testSaveAndFind() {
+		JobExecution exec = new JobExecution(jobInstance);
+		dao.saveJobExecution(exec);
+
+		List executions = dao.findJobExecutions(jobInstance);
+		assertTrue(executions.size() == 1);
+		assertEquals(exec, executions.get(0));
+	}
+	
+	/**
+	 * Saving sets id to the entity.
+	 */
+	public void testSaveAddsId() {
+		JobExecution exec = new JobExecution(jobInstance);
+		assertNull(exec.getId());
+		dao.saveJobExecution(exec);
+		assertNotNull(exec.getId());
+	}
+	/**
+	 * Execution count increases by one with every save
+	 * for the same job instance.
+	 */
+	public void testGetExecutionCount() {
+		JobExecution exec1 = new JobExecution(jobInstance);
+		JobExecution exec2 = new JobExecution(jobInstance);
+		
+		dao.saveJobExecution(exec1);
+		assertEquals(1, dao.getJobExecutionCount(jobInstance));
+		
+		dao.saveJobExecution(exec2);
+		assertEquals(2, dao.getJobExecutionCount(jobInstance));
+	}
+}

spring-batch-execution/src/test/java/org/springframework/batch/execution/repository/dao/MapJobInstanceDaoTests.java

@@ -0,0 +1,38 @@
+package org.springframework.batch.execution.repository.dao;
+
+import junit.framework.TestCase;
+
+import org.springframework.batch.core.domain.Job;
+import org.springframework.batch.core.domain.JobInstance;
+import org.springframework.batch.core.domain.JobParameters;
+import org.springframework.batch.core.domain.JobParametersBuilder;
+import org.springframework.batch.execution.job.JobSupport;
+
+public class MapJobInstanceDaoTests extends TestCase {
+
+	JobInstanceDao dao = new MapJobInstanceDao();
+	
+	protected void setUp() throws Exception {
+		MapJobInstanceDao.clear();
+	}
+
+	protected void tearDown() throws Exception {
+		MapJobInstanceDao.clear();
+	}
+
+	/**
+	 * Create and retrieve a job instance.
+	 */
+	public void testCreateAndRetrieve() throws Exception {
+		Job fooJob = new JobSupport("foo");
+		JobParameters fooParams = new JobParametersBuilder().addString("fooKey", "fooValue").toJobParameters();
+		
+		JobInstance fooInstance = dao.createJobInstance(fooJob, fooParams);
+		assertNotNull(fooInstance.getId());
+		assertEquals(fooJob, fooInstance.getJob());
+		assertEquals(fooParams, fooInstance.getJobParameters());
+		
+		JobInstance retrievedInstance = dao.getJobInstance(fooJob, fooParams);
+		assertEquals(fooInstance, retrievedInstance);
+	}
+}

spring-batch-execution/src/test/java/org/springframework/batch/execution/step/ItemOrientedStepTests.java

@@ -32,7 +32,8 @@ import org.springframework.batch.core.domain.StepContribution;
 import org.springframework.batch.core.domain.StepExecution;
 import org.springframework.batch.execution.job.JobSupport;
 import org.springframework.batch.execution.repository.SimpleJobRepository;
-import org.springframework.batch.execution.repository.dao.MapJobDao;
+import org.springframework.batch.execution.repository.dao.MapJobExecutionDao;
+import org.springframework.batch.execution.repository.dao.MapJobInstanceDao;
 import org.springframework.batch.execution.repository.dao.MapStepDao;
 import org.springframework.batch.execution.scope.StepSynchronizationManager;
 import org.springframework.batch.execution.step.support.JobRepositorySupport;
@@ -195,7 +196,7 @@ public class ItemOrientedStepTests extends TestCase {
 
 	public void testRepository() throws Exception {
 
-		SimpleJobRepository repository = new SimpleJobRepository(new MapJobDao(), new MapJobDao(), new MapStepDao());
+		SimpleJobRepository repository = new SimpleJobRepository(new MapJobInstanceDao(), new MapJobExecutionDao(), new MapStepDao());
 		itemOrientedStep.setJobRepository(repository);
 
 		Step step = new StepSupport("stepName");

spring-batch-execution/src/test/java/org/springframework/batch/execution/step/support/StepExecutorInterruptionTests.java

@@ -29,7 +29,8 @@ import org.springframework.batch.execution.job.JobSupport;
 import org.springframework.batch.execution.repository.SimpleJobRepository;
 import org.springframework.batch.execution.repository.dao.JobExecutionDao;
 import org.springframework.batch.execution.repository.dao.JobInstanceDao;
-import org.springframework.batch.execution.repository.dao.MapJobDao;
+import org.springframework.batch.execution.repository.dao.MapJobExecutionDao;
+import org.springframework.batch.execution.repository.dao.MapJobInstanceDao;
 import org.springframework.batch.execution.repository.dao.MapStepDao;
 import org.springframework.batch.execution.repository.dao.StepExecutionDao;
 import org.springframework.batch.execution.step.ItemOrientedStep;
@@ -44,16 +45,17 @@ public class StepExecutorInterruptionTests extends TestCase {
 
 	private JobRepository jobRepository;
 
-	private JobInstanceDao jobInstanceDao = new MapJobDao();
+	private JobInstanceDao jobInstanceDao = new MapJobInstanceDao();
 	
-	private JobExecutionDao jobExecutionDao = new MapJobDao();
+	private JobExecutionDao jobExecutionDao = new MapJobExecutionDao();
 
 	private StepExecutionDao stepExecutionDao = new MapStepDao();
 
 	private ItemOrientedStep step;
 
 	public void setUp() throws Exception {
-		MapJobDao.clear();
+		MapJobInstanceDao.clear();
+		MapJobExecutionDao.clear();
 		MapStepDao.clear();
 		
 		jobRepository = new SimpleJobRepository(jobInstanceDao, jobExecutionDao, stepExecutionDao);

spring-batch-execution/src/test/resources/simple-container-definition.xml

@@ -44,13 +44,17 @@
 
 	<bean id="simpleJobRepository"
 		class="org.springframework.batch.execution.repository.SimpleJobRepository">
-		<constructor-arg ref="jobDao" />
-		<constructor-arg ref="jobDao" />
+		<constructor-arg ref="jobInstanceDao" />
+		<constructor-arg ref="jobExecutionDao" />
 		<constructor-arg ref="stepDao" />
 	</bean>
 
-	<bean id="jobDao"
-		class="org.springframework.batch.execution.repository.dao.MapJobDao" />
+	<bean id="jobInstanceDao"
+		class="org.springframework.batch.execution.repository.dao.MapJobInstanceDao" />
+	<!-- init-method="clear"/-->
+	
+	<bean id="jobExecutionDao"
+		class="org.springframework.batch.execution.repository.dao.MapJobExecutionDao" />
 	<!-- init-method="clear"/-->
 
 	<bean id="stepDao"

spring-batch-samples/src/main/resources/simple-container-definition.xml

@@ -71,10 +71,13 @@
 			ref="stepExecutionIncrementer" />
 	</bean>
 
-	<bean id="mapJobDao" lazy-init="true"
-		class="org.springframework.batch.execution.repository.dao.MapJobDao" />
+	<bean id="mapJobInstanceDao" lazy-init="true"
+		class="org.springframework.batch.execution.repository.dao.MapJobInstanceDao" />
+		
+	<bean id="mapJobExecutionDao" lazy-init="true"
+		class="org.springframework.batch.execution.repository.dao.MapJobExecutionDao" />
 
-	<bean id="mapStepDao" lazy-init="true"
+	<bean id="mapStepExecutionDao" lazy-init="true"
 		class="org.springframework.batch.execution.repository.dao.MapStepDao" />
 
 	<bean id="jdbcTemplate"