BATCH-1743: loosen partition handler validation

spring-batch-core/src/main/java/org/springframework/batch/core/configuration/xml/StepParserStepFactoryBean.java

@@ -284,10 +284,7 @@ class StepParserStepFactoryBean<I, O> implements FactoryBean, BeanNameAware {
 		Assert.state(partitioner != null, "A Partitioner must be provided for a partition step");
 		configureAbstractStep(ts);
 
-		PartitionHandler handler;
-
 		if (partitionHandler != null) {
-			handler = partitionHandler;
 			ts.setPartitionHandler(partitionHandler);
 		}
 		else {
@@ -299,29 +296,23 @@ class StepParserStepFactoryBean<I, O> implements FactoryBean, BeanNameAware {
 			partitionHandler.setGridSize(gridSize);
 			partitionHandler.setTaskExecutor(taskExecutor);
 			ts.setPartitionHandler(partitionHandler);
-			handler = partitionHandler;
 		}
 
-		PartitionHandler targetHandler = (PartitionHandler) extractTarget(handler, PartitionHandler.class);
 		// BATCH-1659
-		if (targetHandler instanceof TaskExecutorPartitionHandler) {
-			// Only for a local partition handler is the step required
-			Assert.state(step != null,
-					"A Step must be provided for a partition step with a TaskExecutorPartitionHandler");
-			try {
-				TaskExecutorPartitionHandler taskExecutorPartitionHandler = (TaskExecutorPartitionHandler) targetHandler;
-				taskExecutorPartitionHandler.setStep(step);
-				taskExecutorPartitionHandler.afterPropertiesSet();
+		if (partitionHandler instanceof TaskExecutorPartitionHandler) {
+			TaskExecutorPartitionHandler taskExecutorPartitionHandler = (TaskExecutorPartitionHandler) partitionHandler;
+			if (taskExecutorPartitionHandler.getStep() == null) {
+				// Only for a local partition handler is the step required
+				Assert.state(step != null,
+						"A Step must be provided for a partition step with a TaskExecutorPartitionHandler");
+				try {
+					taskExecutorPartitionHandler.setStep(step);
+					taskExecutorPartitionHandler.afterPropertiesSet();
+				}
+				catch (Exception e) {
+					throw new BeanCreationException("Could not configure TaskExecutorPartitionHandler", e);
+				}
 			}
-			catch (Exception e) {
-				throw new BeanCreationException("Could not configure TaskExecutorPartitionHandler", e);
-			}
-		}
-		else {
-			// Only for a local partition handler is the step required
-			Assert.state(step == null,
-					"A Step must not be provided for a custom partition handler (unless it extends TaskExecutorPartitionHandler). "
-							+ "It should be configured with its own step reference.");
 		}
 
 		boolean allowStartIfComplete = this.allowStartIfComplete != null ? this.allowStartIfComplete : false;
@@ -671,7 +662,7 @@ class StepParserStepFactoryBean<I, O> implements FactoryBean, BeanNameAware {
 	public void setPartitioner(Partitioner partitioner) {
 		this.partitioner = partitioner;
 	}
-	
+
 	/**
 	 * @param stepExecutionAggregator the stepExecutionAggregator to set
 	 */

spring-batch-core/src/test/java/org/springframework/batch/core/configuration/xml/PartitionStepWithLateBindingParserTests.java

@@ -0,0 +1,93 @@
+/*
+ * 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.core.configuration.xml;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.batch.core.BatchStatus;
+import org.springframework.batch.core.Job;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.core.JobParametersBuilder;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+/**
+ * @author Dave Syer
+ * @author Josh Long
+ */
+@ContextConfiguration
+@RunWith(SpringJUnit4ClassRunner.class)
+public class PartitionStepWithLateBindingParserTests {
+
+	@Autowired
+	@Qualifier("job1")
+	private Job job1;
+
+	@Autowired
+	@Qualifier("nameStoringTasklet")
+	private NameStoringTasklet nameStoringTasklet;
+
+	@Autowired
+	private JobRepository jobRepository;
+
+	@Autowired
+	private MapJobRepositoryFactoryBean mapJobRepositoryFactoryBean;
+
+	private List<String> savedStepNames = new ArrayList<String>();
+
+	@Before
+	public void setUp() {
+		nameStoringTasklet.setStepNamesList(savedStepNames);
+		mapJobRepositoryFactoryBean.clear();
+	}
+
+	@Test
+	public void testExplicitHandlerStep() throws Exception {
+		assertNotNull(job1);
+		JobExecution jobExecution = jobRepository.createJobExecution(job1.getName(), new JobParametersBuilder()
+				.addLong("gridSize", 1L).toJobParameters());
+		job1.execute(jobExecution);
+		assertEquals(BatchStatus.COMPLETED, jobExecution.getStatus());
+		Collections.sort(savedStepNames);
+		assertEquals("[s1:partition0]", savedStepNames.toString());
+		List<String> stepNames = getStepNames(jobExecution);
+		assertEquals(2, stepNames.size());
+		assertEquals("[s1, s1:partition0]", stepNames.toString());
+	}
+
+	private List<String> getStepNames(JobExecution jobExecution) {
+		List<String> list = new ArrayList<String>();
+		for (StepExecution stepExecution : jobExecution.getStepExecutions()) {
+			list.add(stepExecution.getStepName());
+		}
+		Collections.sort(list);
+		return list;
+	}
+
+}

spring-batch-core/src/test/java/org/springframework/batch/core/configuration/xml/StepParserStepFactoryBeanTests.java

@@ -272,8 +272,9 @@ public class StepParserStepFactoryBeanTests {
 
 		SimplePartitioner partitioner = new SimplePartitioner();
 		fb.setPartitioner(partitioner);
-		fb.setStep(new StepSupport("foo"));
-		ProxyFactory factory = new ProxyFactory(new TaskExecutorPartitionHandler());
+		TaskExecutorPartitionHandler partitionHandler = new TaskExecutorPartitionHandler();
+		partitionHandler.setStep(new StepSupport("foo"));
+		ProxyFactory factory = new ProxyFactory(partitionHandler);
 		fb.setPartitionHandler((PartitionHandler) factory.getProxy());
 
 		Object step = fb.getObject();

spring-batch-core/src/test/resources/org/springframework/batch/core/configuration/xml/PartitionStepWithLateBindingParserTests-context.xml

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans:beans xmlns="http://www.springframework.org/schema/batch" xmlns:beans="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://www.springframework.org/schema/batch http://www.springframework.org/schema/batch/spring-batch-2.1.xsd
+	http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
+
+	<beans:import resource="common-context.xml" />
+
+	<job id="job1">
+		<step id="s1">
+			<partition partitioner="partitioner" handler="handler"/>
+		</step>
+	</job>
+
+	<bean id="handler" class="org.springframework.batch.core.partition.support.TaskExecutorPartitionHandler" scope="step"
+		xmlns="http://www.springframework.org/schema/beans">
+		<property name="gridSize" value="#{jobParameters['gridSize']}" />
+		<property name="step" ref="step1"/>
+	</bean>
+
+	<beans:bean id="partitioner" class="org.springframework.batch.core.partition.support.SimplePartitioner" />
+
+</beans:beans>