Code cleanup

- Inline variables
- Remove unused variables
- Remove redundant array creation
- Remove redundant `@SuppressWarnings`
- Remove unnecessary exceptions from throws list
- Remove redundant initializers
- Use List.subList().clear() where appropriate
- Use try-with-resources where needed
- Use pattern variables where appropriate

spring-batch-integration/src/main/java/org/springframework/batch/integration/async/AsyncItemProcessor.java

@@ -115,8 +115,7 @@ public class AsyncItemProcessor<I, O> implements ItemProcessor<I, Future<O>>, In
 		if (context == null) {
 			return null;
 		}
-		StepExecution stepExecution = context.getStepExecution();
-		return stepExecution;
+		return context.getStepExecution();
 	}
 
 }