SSDM-13579: Added new test BaseApiClientTest.resumeWrite_zeroOffset_createsFile().

api-data-store-server-java/src/main/java/ch/ethz/sis/afsclient/client/AfsClient.java

@@ -15,6 +15,7 @@ import java.nio.file.StandardOpenOption;
 import java.security.MessageDigest;
 import java.time.Duration;
 import java.util.AbstractMap;
+import java.util.Arrays;
 import java.util.Base64;
 import java.util.HashMap;
 import java.util.List;
@@ -322,7 +323,7 @@ public final class AfsClient implements PublicAPI, ClientAPI
             {
                 final ByteBuffer byteBuffer = ByteBuffer.allocate(DEFAULT_PACKAGE_SIZE_IN_BYTES);
                 fileChannel.read(byteBuffer, offset, byteBuffer,
-                        new ChannelReadCompletionHandler(owner, destination, byteBuffer, offset, latch, hasError));
+                        new ChannelReadCompletionHandler(owner, destination, offset, latch, hasError));
                 offset += DEFAULT_PACKAGE_SIZE_IN_BYTES;
             }
 
@@ -543,8 +544,6 @@ public final class AfsClient implements PublicAPI, ClientAPI
     private class ChannelReadCompletionHandler implements CompletionHandler<Integer, ByteBuffer>
     {
 
-        private final ByteBuffer byteBuffer;
-
         private final @NonNull String owner;
 
         private final @NonNull String destination;
@@ -555,11 +554,9 @@ public final class AfsClient implements PublicAPI, ClientAPI
 
         private final Long offset;
 
-        public ChannelReadCompletionHandler(final @NonNull String owner, final @NonNull String destination, final ByteBuffer byteBuffer,
-                final Long offset, final CountDownLatch latch,
-                final AtomicBoolean hasError)
+        public ChannelReadCompletionHandler(final @NonNull String owner, final @NonNull String destination, final Long offset,
+                final CountDownLatch latch, final AtomicBoolean hasError)
         {
-            this.byteBuffer = byteBuffer;
             this.owner = owner;
             this.destination = destination;
             this.offset = offset;
@@ -570,7 +567,8 @@ public final class AfsClient implements PublicAPI, ClientAPI
         @Override
         public void completed(final Integer result, final ByteBuffer attachment)
         {
-            final byte[] data = byteBuffer.array();
+            final byte[] fullBuffer = attachment.array();
+            final byte[] data = result < fullBuffer.length ? Arrays.copyOf(fullBuffer, result) : fullBuffer;
             try
             {
                 final Boolean writeSuccessful = write(owner, destination, this.offset, data, getMD5(data));

server-data-store/src/test/java/ch/ethz/sis/afsserver/client/BaseApiClientTest.java

@@ -195,6 +195,17 @@ public abstract class BaseApiClientTest
         assertArrayEquals(DATA, testDataFile);
     }
 
+    @Test
+    public void resumeWrite_zeroOffset_createsFile() throws Exception
+    {
+        login();
+
+        final Boolean result = afsClient.resumeWrite(owner, FILE_B, Path.of(IOUtils.getPath(testDataRoot, FILE_A)), 0L);
+        assertTrue(result);
+
+        assertFilesEqual(IOUtils.getPath(testDataRoot, FILE_A), FILE_B);
+    }
+
     @Test
     public void delete_fileIsGone() throws Exception
     {