How to handle resource cleanup with CompletableFuture in Java 11 when exceptions occur?
I'm currently working on a Java 11 application that uses `CompletableFuture` for asynchronous processing... I have a set of tasks where I need to read data from a file, process it, and then write the results to a database. I noticed that when an exception occurs during file reading, it doesn't seem to trigger any cleanup logic I've set up for database connections. Here's a simplified version of my code: ```java import java.nio.file.Files; import java.nio.file.Paths; import java.util.concurrent.CompletableFuture; public class AsyncFileProcessor { public void processFile(String filePath) { CompletableFuture<Void> future = CompletableFuture.runAsync(() -> { try { String content = new String(Files.readAllBytes(Paths.get(filePath))); // Simulate processing if (content.isEmpty()) { throw new RuntimeException("File is empty!"); } // Proceed to write to database writeToDatabase(content); } catch (Exception e) { // Handle the exception System.err.println("Error processing file: " + e.getMessage()); } }); // Add a completion handler to clean up resources future.whenComplete((result, throwable) -> { cleanupResources(); }); } private void writeToDatabase(String content) { // Write to database logic goes here. } private void cleanupResources() { // Cleanup logic, like closing database connections. System.out.println("Resources cleaned up."); } } ``` When I run this code and the file is empty, I see the error message printed, but the cleanup logic in `cleanupResources()` is not being executed. Instead, the `whenComplete` block is still invoked, but it seems to get skipped because of the exception thrown in the `runAsync` method. I've tried adding a `handle` method instead of `whenComplete`, but it still doesn't execute the cleanup as expected. Is there a recommended way to ensure that my cleanup logic runs even when an exception occurs in the asynchronous task? Am I missing something in the way I'm handling exceptions with `CompletableFuture`?