in hadoop-api-shim/src/main/java/org/apache/hadoop/fs/shim/functional/FutureIO.java [261:275]
public static <T> CompletableFuture<T> eval(
CallableRaisingIOE<T> callable) {
CompletableFuture<T> result = new CompletableFuture<>();
try {
result.complete(callable.apply());
} catch (UnsupportedOperationException | IllegalArgumentException tx) {
// fail fast here
throw tx;
} catch (Throwable tx) {
// fail lazily here to ensure callers expect all File IO operations to
// surface later
result.completeExceptionally(tx);
}
return result;
}