IN PROGRESS - issue BATCH-891: Create Annotations

http://jira.springframework.org/browse/BATCH-891

Added a post processor that checks for annotations. (still under development)

spring-batch-core/src/main/java/org/springframework/batch/core/annotation/StepComponentBeanPostProcessor.java

@@ -0,0 +1,134 @@
+/**
+ * 
+ */
+package org.springframework.batch.core.annotation;
+
+import java.lang.reflect.Method;
+
+import org.springframework.aop.framework.ProxyFactory;
+import org.springframework.aop.support.DefaultIntroductionAdvisor;
+import org.springframework.aop.support.DelegatingIntroductionInterceptor;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.StepExecutionListener;
+import org.springframework.batch.core.step.AbstractStep;
+import org.springframework.batch.repeat.ExitStatus;
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.FactoryBean;
+import org.springframework.beans.factory.config.BeanPostProcessor;
+import org.springframework.core.Ordered;
+import org.springframework.core.annotation.AnnotationUtils;
+
+
+/**
+ * @author Lucas Ward
+ * 
+ */
+public class StepComponentBeanPostProcessor implements BeanPostProcessor, Ordered {
+
+	private AbstractStep step;
+	private String basePackage;
+
+	public StepComponentBeanPostProcessor(AbstractStep step, String basePackage) {
+		this.step = step;
+		this.basePackage = basePackage;
+	}
+
+	public Object postProcessAfterInitialization(Object bean, String beanName)
+			throws BeansException {
+		// if it implements the StepExecutionListener interface, we'll register
+		// it directly as such
+
+		if (bean instanceof StepExecutionListener) {
+			step.registerStepExecutionListener((StepExecutionListener) bean);
+		}
+
+		Class<?> clazz = bean.getClass();
+		if(bean instanceof FactoryBean){
+			clazz = ((FactoryBean)bean).getObjectType();
+		}
+
+		// If the class isn't of the correct package, isn't annotated with the
+		// BatchComponent annotation, we won't put it in.
+		if (!clazz.getName().startsWith(basePackage)
+				|| AnnotationUtils.findAnnotation(clazz, BatchComponent.class) == null) {
+			return bean;
+		}
+
+		ProxyFactory proxyFactory = new ProxyFactory(
+				new Class[] { StepExecutionListener.class });
+
+		StepExecutionListenerMixin listenerMixin = new StepExecutionListenerMixin(bean);
+		
+		Method[] methods = clazz.getMethods();
+		for (Method method : methods) {
+			if(AnnotationUtils.findAnnotation(method, BeforeStep.class) != null){
+				listenerMixin.setBeforeStepMethod(method);
+			}
+			
+			if(AnnotationUtils.findAnnotation(method, AfterStep.class) != null){
+				listenerMixin.setAfterStepMethod(method);
+			}
+		}
+		
+		proxyFactory.addAdvisor(new DefaultIntroductionAdvisor(listenerMixin, StepExecutionListener.class));
+		StepExecutionListener listener = (StepExecutionListener)proxyFactory.getProxy();
+		step.registerStepExecutionListener(listener);
+
+		return null;
+	}
+
+	public Object postProcessBeforeInitialization(Object bean, String beanName)
+			throws BeansException {
+
+		return bean;
+	}
+	
+	private class StepExecutionListenerMixin extends DelegatingIntroductionInterceptor implements StepExecutionListener{
+
+		Object bean;
+		Method afterStepMethod;
+		Method beforeStepMethod;
+		
+		public StepExecutionListenerMixin(Object bean) {
+			this.bean = bean;
+		}
+		
+		public void setBeforeStepMethod(Method beforeStepMethod) {
+			this.beforeStepMethod = beforeStepMethod;
+		}
+		
+		public void setAfterStepMethod(Method afterStepMethod) {
+			this.afterStepMethod = afterStepMethod;
+		}
+		
+		public ExitStatus afterStep(StepExecution stepExecution) {
+			if(afterStepMethod != null){
+				invokeMethod(afterStepMethod, bean);
+			}
+			return null;
+		}
+
+		public void beforeStep(StepExecution stepExecution) {
+			if(beforeStepMethod != null){
+				invokeMethod(beforeStepMethod, bean);
+			}
+		}
+	}
+	
+	private Object invokeMethod(Method method, Object bean, Object... args){
+		
+		try {
+			return method.invoke(bean, args);
+		} catch (Exception e) {
+			if(e instanceof RuntimeException){
+				throw (RuntimeException)e;
+			}
+			throw new IllegalArgumentException("Failed to invoke method: [" + method + "]");
+		} 
+	}
+
+	public int getOrder() {
+		return Ordered.LOWEST_PRECEDENCE;
+	}
+	
+}

spring-batch-core/src/test/java/org/springframework/batch/core/annotation/StepComponentBeanPostProcessorIntegrationTests.java

@@ -0,0 +1,31 @@
+package org.springframework.batch.core.annotation;
+
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.batch.core.JobParameters;
+import org.springframework.batch.core.job.SimpleJob;
+import org.springframework.batch.core.launch.JobLauncher;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(locations={"component-scan-context.xml"})
+public class StepComponentBeanPostProcessorIntegrationTests {
+
+	@Autowired
+	private SimpleJob job;
+	
+	@Autowired
+	private JobLauncher jobLauncher;
+	
+	@Test
+	public void testListener() throws Exception{
+		
+		jobLauncher.run(job, new JobParameters());
+		
+	//	assertTrue(TestComponent.isAfterStepCalled());
+	//	assertTrue(TestComponent.isBeforeStepCalled());
+	}
+}

spring-batch-core/src/test/java/org/springframework/batch/core/annotation/StepComponentBeanPostProcessorTests.java

@@ -0,0 +1,55 @@
+/**
+ * 
+ */
+package org.springframework.batch.core.annotation;
+
+import static org.easymock.EasyMock.createMock;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+import org.springframework.batch.core.JobExecution;
+import org.springframework.batch.core.StepExecution;
+import org.springframework.batch.core.repository.JobRepository;
+import org.springframework.batch.core.step.AbstractStep;
+import org.springframework.batch.repeat.ExitStatus;
+
+
+/**
+ * @author Lucas Ward
+ *
+ */
+public class StepComponentBeanPostProcessorTests {
+	
+	@BatchComponent
+	private class TestComponent {
+		
+		boolean afterStepCalled = false;
+		
+		@AfterStep
+		public void testMethod(){
+			afterStepCalled = true;
+		}
+	}
+	
+	@Test
+	public void testNormalCase() throws Exception{
+		AbstractStep step = new StubStep();
+		step.setJobRepository(createMock(JobRepository.class));
+		StepComponentBeanPostProcessor postProcessor = new StepComponentBeanPostProcessor(step, "org.springframework.batch.core.annotation");
+		TestComponent testComponent = new TestComponent();
+		postProcessor.postProcessAfterInitialization(testComponent, "testComponent");
+		step.execute(new StepExecution("teststep", new JobExecution(11L)));
+		assertTrue(testComponent.afterStepCalled);
+	}
+	
+	private class StubStep extends AbstractStep{
+
+		@Override
+		protected ExitStatus doExecute(StepExecution stepExecution)
+				throws Exception {
+			// TODO Auto-generated method stub
+			return ExitStatus.FINISHED;
+		}
+		
+	}
+}

spring-batch-core/src/test/java/org/springframework/batch/core/annotation/TestComponent.java

@@ -10,4 +10,25 @@ package org.springframework.batch.core.annotation;
 @BatchComponent
 public class TestComponent {
 
+	private static boolean beforeStepCalled = false;
+	
+	private static boolean afterStepCalled = false;
+	
+	public static boolean isBeforeStepCalled(){
+		return beforeStepCalled;
+	}
+	
+	public static boolean isAfterStepCalled(){
+		return afterStepCalled;
+	}
+	
+	@BeforeStep
+	public void beforeStep(){
+		beforeStepCalled = true;
+	}
+	
+	@AfterStep
+	public void afterStep(){
+		afterStepCalled = true;
+	}
 }

spring-batch-core/src/test/resources/org/springframework/batch/core/annotation/component-scan-context.xml

@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:context="http://www.springframework.org/schema/context"
+	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
+		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
+	
+	<context:component-scan base-package="org.springframework.batch.core.annotation"
+		scope-resolver="org.springframework.batch.core.annotation.BatchComponentScopeMetaDataResolver"
+		>
+		<context:include-filter type="annotation" expression="org.springframework.batch.core.annotation.BatchComponent"/>
+		
+	</context:component-scan>
+	
+	<bean id="job" class="org.springframework.batch.core.job.SimpleJob" >
+		<property name="steps">
+			<list>
+				<ref bean="step"/>
+			</list>
+		</property>
+		<property name="jobRepository" ref="jobRepository" />
+	</bean>
+	
+	<bean id="jobRepository" class="org.springframework.batch.core.repository.support.MapJobRepositoryFactoryBean" >
+		<property name="transactionManager">
+			<bean class="org.springframework.batch.support.transaction.ResourcelessTransactionManager" />
+		</property>
+	</bean>
+	
+	<bean id="step" class="org.springframework.batch.core.step.tasklet.TaskletStep" >
+		<property name="tasklet">
+			<bean class="org.springframework.batch.core.configuration.xml.DummyTasklet" />
+		</property>
+		<property name="jobRepository" ref="jobRepository" />
+		<property name="transactionManager">
+			<bean class="org.springframework.batch.support.transaction.ResourcelessTransactionManager" />
+		</property>
+	</bean>
+	
+	<bean class="org.springframework.batch.core.annotation.StepComponentBeanPostProcessor" >
+		<constructor-arg ref="step" />
+		<constructor-arg value="org.springframework.batch.core.annotation" />
+	</bean>
+	
+	<bean class="org.springframework.batch.core.launch.support.SimpleJobLauncher" >
+		<property name="jobRepository" ref="jobRepository" />
+	</bean>
+
+</beans>