Refine jSpecify nullability checks

Issue #4673

Author: fmbenhassine

spring-batch-core/src/main/java/org/springframework/batch/core/configuration/support/DefaultBatchConfiguration.java

@@ -16,7 +16,6 @@
 package org.springframework.batch.core.configuration.support;
 
 import io.micrometer.observation.ObservationRegistry;
-import org.jspecify.annotations.NullUnmarked;
 
 import org.springframework.batch.core.configuration.DuplicateJobException;
 import org.springframework.batch.core.configuration.annotation.BatchObservabilityBeanPostProcessor;
@@ -79,9 +78,9 @@
  */
 @Configuration(proxyBeanMethods = false)
 @Import({ ScopeConfiguration.class, BatchObservabilityBeanPostProcessor.class })
-@NullUnmarked
 public class DefaultBatchConfiguration implements ApplicationContextAware {
 
+	@SuppressWarnings("NullAway.Init")
 	protected ApplicationContext applicationContext;
 
 	@Override

spring-batch-core/src/main/java/org/springframework/batch/core/configuration/support/MapJobRegistry.java

@@ -23,7 +23,7 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.jspecify.annotations.NullUnmarked;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.batch.core.job.Job;
 import org.springframework.batch.core.configuration.DuplicateJobException;
@@ -43,7 +43,6 @@
  * @author Robert Fischer
  * @author Mahmoud Ben Hassine
  */
-@NullUnmarked // FIXME how to fix nullability checks for the applicationContext field?
 public class MapJobRegistry implements JobRegistry, SmartInitializingSingleton, ApplicationContextAware {
 
 	protected final Log logger = LogFactory.getLog(getClass());
@@ -53,6 +52,7 @@ public class MapJobRegistry implements JobRegistry, SmartInitializingSingleton,
 	 */
 	private final ConcurrentMap<String, Job> map = new ConcurrentHashMap<>();
 
+	@SuppressWarnings("NullAway.Init")
 	private ApplicationContext applicationContext;
 
 	@Override
@@ -83,6 +83,7 @@ public void unregister(String name) {
 		this.map.remove(name);
 	}
 
+	@Nullable
 	@Override
 	public Job getJob(String name) {
 		return this.map.get(name);

spring-batch-core/src/main/java/org/springframework/batch/core/job/AbstractJob.java

@@ -60,7 +60,8 @@
  * @author Dave Syer
  * @author Mahmoud Ben Hassine
  */
-@NullUnmarked // FIXME to remove once default constructors are removed
+@NullUnmarked // FIXME to remove once default constructors (required by the batch XML
+				// namespace) are removed
 public abstract class AbstractJob implements Job, StepLocator, BeanNameAware, InitializingBean {
 
 	protected static final Log logger = LogFactory.getLog(AbstractJob.class);

spring-batch-core/src/main/java/org/springframework/batch/core/job/SimpleJob.java

@@ -40,7 +40,8 @@
  * @author Michael Minella
  * @author Mahmoud Ben Hassine
  */
-@NullUnmarked // FIXME to remove once default constructors are removed
+@NullUnmarked // FIXME to remove once default constructors (required by the batch XML
+				// namespace) are removed
 public class SimpleJob extends AbstractJob {
 
 	private final List<Step> steps = new ArrayList<>();

spring-batch-core/src/main/java/org/springframework/batch/core/job/builder/FlowJobBuilder.java

@@ -32,7 +32,8 @@
  * @author Mahmoud Ben Hassine
  * @since 2.2
  */
-@NullUnmarked // FIXME to remove once default constructors are removed
+@NullUnmarked // FIXME to remove once default constructors (required by the batch XML
+				// namespace) are removed
 public class FlowJobBuilder extends JobBuilderHelper<FlowJobBuilder> {
 
 	private Flow flow;

spring-batch-core/src/main/java/org/springframework/batch/core/job/builder/JobBuilderHelper.java

@@ -46,7 +46,8 @@
  * @author Taeik Lim
  * @since 2.2
  */
-@NullUnmarked // FIXME to remove once default constructors are removed
+@NullUnmarked // FIXME to remove once default constructors (required by the batch XML
+				// namespace) are removed
 public abstract class JobBuilderHelper<B extends JobBuilderHelper<B>> {
 
 	protected final Log logger = LogFactory.getLog(getClass());

spring-batch-core/src/main/java/org/springframework/batch/core/job/builder/SimpleJobBuilder.java

@@ -33,7 +33,8 @@
  * @since 2.2
  *
  */
-@NullUnmarked // FIXME to remove once default constructors are removed
+@NullUnmarked // FIXME to remove once default constructors (required by the batch XML
+				// namespace) are removed
 public class SimpleJobBuilder extends JobBuilderHelper<SimpleJobBuilder> {
 
 	private final List<Step> steps = new ArrayList<>();

spring-batch-core/src/main/java/org/springframework/batch/core/launch/support/JobOperatorFactoryBean.java

@@ -20,7 +20,7 @@
 import io.micrometer.observation.ObservationRegistry;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.jspecify.annotations.NullUnmarked;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.aop.framework.ProxyFactory;
 import org.springframework.batch.core.configuration.BatchConfigurationException;
@@ -58,26 +58,29 @@
  * @author Mahmoud Ben Hassine
  * @since 5.0
  */
-@NullUnmarked
 public class JobOperatorFactoryBean implements FactoryBean<JobOperator>, ApplicationContextAware, InitializingBean {
 
 	protected static final Log logger = LogFactory.getLog(JobOperatorFactoryBean.class);
 
+	@SuppressWarnings("NullAway.Init")
 	private ApplicationContext applicationContext;
 
-	private PlatformTransactionManager transactionManager;
+	private @Nullable PlatformTransactionManager transactionManager;
 
-	private TransactionAttributeSource transactionAttributeSource;
+	private @Nullable TransactionAttributeSource transactionAttributeSource;
 
+	@SuppressWarnings("NullAway.Init")
 	private JobRegistry jobRegistry;
 
+	@SuppressWarnings("NullAway.Init")
 	private JobRepository jobRepository;
 
 	private JobParametersConverter jobParametersConverter = new DefaultJobParametersConverter();
 
+	@SuppressWarnings("NullAway.Init")
 	private TaskExecutor taskExecutor;
 
-	private ObservationRegistry observationRegistry;
+	private @Nullable ObservationRegistry observationRegistry;
 
 	private final ProxyFactory proxyFactory = new ProxyFactory();
 
@@ -192,6 +195,7 @@ public boolean isSingleton() {
 		return true;
 	}
 
+	@SuppressWarnings("DataFlowIssue")
 	@Override
 	public JobOperator getObject() throws Exception {
 		TransactionInterceptor advice = new TransactionInterceptor((TransactionManager) this.transactionManager,
@@ -203,7 +207,7 @@ public JobOperator getObject() throws Exception {
 		return (JobOperator) this.proxyFactory.getProxy(getClass().getClassLoader());
 	}
 
-	@SuppressWarnings("removal")
+	@SuppressWarnings({ "removal" })
 	private TaskExecutorJobOperator getTarget() throws Exception {
 		TaskExecutorJobOperator taskExecutorJobOperator = new TaskExecutorJobOperator();
 		taskExecutorJobOperator.setJobRegistry(this.jobRegistry);

spring-batch-core/src/main/java/org/springframework/batch/core/launch/support/TaskExecutorJobOperator.java

@@ -19,7 +19,7 @@
 import io.micrometer.observation.ObservationRegistry;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.jspecify.annotations.NullUnmarked;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.batch.core.configuration.JobRegistry;
 import org.springframework.batch.core.job.Job;
@@ -60,12 +60,11 @@
  * @since 6.0
  */
 @SuppressWarnings("removal")
-@NullUnmarked
 public class TaskExecutorJobOperator extends SimpleJobOperator {
 
 	private static final Log logger = LogFactory.getLog(TaskExecutorJobOperator.class.getName());
 
-	protected ObservationRegistry observationRegistry;
+	protected @Nullable ObservationRegistry observationRegistry;
 
 	@Override
 	public void afterPropertiesSet() throws Exception {

spring-batch-core/src/main/java/org/springframework/batch/core/listener/ExecutionContextPromotionListener.java

@@ -15,7 +15,7 @@
  */
 package org.springframework.batch.core.listener;
 
-import org.jspecify.annotations.NullUnmarked;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.batch.core.ExitStatus;
 import org.springframework.batch.core.job.Job;
@@ -42,17 +42,19 @@
  * @author Mahmoud Ben Hassine
  * @since 2.0
  */
-@NullUnmarked
 public class ExecutionContextPromotionListener implements StepExecutionListener, InitializingBean {
 
-	private String[] keys = null;
+	private String @Nullable [] keys = null;
 
 	private String[] statuses = new String[] { ExitStatus.COMPLETED.getExitCode() };
 
 	private boolean strict = false;
 
 	@Override
 	public ExitStatus afterStep(StepExecution stepExecution) {
+		if (this.keys == null) {
+			return stepExecution.getExitStatus();
+		}
 		ExecutionContext stepContext = stepExecution.getExecutionContext();
 		ExecutionContext jobContext = stepExecution.getJobExecution().getExecutionContext();
 		String exitCode = stepExecution.getExitStatus().getExitCode();
@@ -73,7 +75,7 @@ public ExitStatus afterStep(StepExecution stepExecution) {
 			}
 		}
 
-		return null;
+		return stepExecution.getExitStatus();
 	}
 
 	@Override