use extensible supplyAsync() and newCompleteableFuture()

Signed-off-by: Bala.FA <bala@minio.io>

Author: balamurugana

api/src/main/java/io/minio/BaseS3Client.java

@@ -62,6 +62,7 @@
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Supplier;
 import java.util.logging.Logger;
 import javax.annotation.Nonnull;
 import okhttp3.Call;
@@ -230,6 +231,14 @@ public void setAwsS3Prefix(@Nonnull String awsS3Prefix) {
   ///////////////////////////////////// HTTP execution methods ////////////////////////////////////
   /////////////////////////////////////////////////////////////////////////////////////////////////
 
+  protected <T> CompletableFuture<T> supplyAsync(Supplier<T> supplier) {
+    return CompletableFuture.supplyAsync(supplier);
+  }
+
+  protected <T> CompletableFuture<T> newCompleteableFuture() {
+    return new CompletableFuture<>();
+  }
+
   private String[] handleRedirectResponse(
       Http.Method method, String bucketName, Response response, boolean retry) {
     String code = null;
@@ -282,7 +291,7 @@ protected CompletableFuture<Response> executeAsync(Http.S3Request s3request, Str
     // }
 
     okhttp3.Request httpRequest = request.httpRequest();
-    CompletableFuture<Response> completableFuture = new CompletableFuture<>();
+    CompletableFuture<Response> completableFuture = newCompleteableFuture();
     httpClient
         .newCall(httpRequest)
         .enqueue(

api/src/main/java/io/minio/MinioAsyncClient.java

@@ -562,7 +562,7 @@ args, new SourceObject(args.source(), response.size(), response.etag())))
   protected CompletableFuture<Integer> calculatePartCount(List<SourceObject> sources) {
     long[] objectSize = {0};
 
-    CompletableFuture<Integer> completableFuture = CompletableFuture.supplyAsync(() -> 0);
+    CompletableFuture<Integer> completableFuture = supplyAsync(() -> 0);
 
     int sourceSize = sources.size();
     for (int i = 0; i < sourceSize; i++) {
@@ -650,7 +650,7 @@ private CompletableFuture<Part[]> uploadParts(
             : null;
 
     int partNumber = 0;
-    CompletableFuture<Part[]> future = CompletableFuture.supplyAsync(() -> new Part[partCount]);
+    CompletableFuture<Part[]> future = supplyAsync(() -> new Part[partCount]);
     for (SourceObject source : args.sources()) {
       long size = source.objectSize();
       if (source.length() != null) {
@@ -1753,7 +1753,7 @@ private CompletableFuture<List<UploadPartResponse>> uploadPartsSequentially(
       ByteBuffer buffer,
       long partSize,
       List<UploadPartResponse> responses) {
-    return CompletableFuture.supplyAsync(
+    return supplyAsync(
             () ->
                 new UploadPartArgs(
                     args,
@@ -1804,7 +1804,7 @@ private CompletableFuture<List<UploadPartResponse>> uploadPartsParallelly(
     AtomicBoolean errorOccurred = new AtomicBoolean(false);
     ConcurrentLinkedQueue<Throwable> exceptions = new ConcurrentLinkedQueue<>();
 
-    return CompletableFuture.supplyAsync(
+    return supplyAsync(
         () -> {
           try {
             // Start uploader workers
@@ -3197,7 +3197,7 @@ public CompletableFuture<ObjectWriteResponse> uploadSnowballObjects(
       UploadSnowballObjectsArgs args) {
     checkArgs(args);
 
-    return CompletableFuture.supplyAsync(
+    return supplyAsync(
             () -> {
               FileOutputStream fos = null;
               BufferedOutputStream bos = null;
@@ -3309,7 +3309,7 @@ public CompletableFuture<PutObjectFanOutResponse> putObjectFanOut(PutObjectFanOu
     checkArgs(args);
     args.validateSse(this.baseUrl.isHttps());
 
-    return CompletableFuture.supplyAsync(
+    return supplyAsync(
             () -> {
               byte[] buf16k = new byte[16384]; // 16KiB buffer for optimization.
               ByteBuffer buffer = new ByteBuffer(args.size());