update PartUploadService#prepareUpload

oss-mgr/src/main/java/cn/reghao/oss/mgr/service/PartUploadService.java

@@ -54,9 +54,10 @@ public class PartUploadService {
         long size = uploadPrepare.getSize();
         String sha256sum = uploadPrepare.getSha256sum();
         DataBlock dataBlock = objectRepository.getBySha256sum(sha256sum);
+        List<FileMeta> fileMetaList = fileMetaMapper.findBySha256sum(sha256sum);
         UploadPrepareRet uploadPrepareRet;
         long randomOffset = 0;
-        if (dataBlock != null) {
+        if (dataBlock != null && !fileMetaList.isEmpty()) {
             if (size > CHUNK_SIZE) {
                 Random random = new Random(size);
                 randomOffset = (long) (random.nextDouble() * (size - CHUNK_SIZE));
@@ -65,7 +66,6 @@ public class PartUploadService {
             boolean exist = true;
             uploadPrepareRet = new UploadPrepareRet(uploadId, SPLIT_SIZE, exist, randomOffset, CHUNK_SIZE);
         } else {
-            long splitNumber = size/SPLIT_SIZE + (size%SPLIT_SIZE != 0 ? 1 : 0);
             uploadPrepareRet = new UploadPrepareRet(uploadId, SPLIT_SIZE);
         }