code: @Override
      public String copyContent(String srcStoreID,
                                String srcSpaceID,
                                String srcContentID,
                                String destStoreID,
                                String destSpaceID,
                                String destContentID) throws ResourceException {
          BrokeredStorageProvider srcProvider = getStorageProvider(srcStoreID);
          BrokeredStorageProvider destProvider = getStorageProvider(destStoreID);
  
          if (srcProvider.equals(destProvider)) {
              return copyContent(srcProvider,
                                 srcSpaceID,
                                 srcContentID,
                                 destSpaceID,
                                 destContentID,
                                 srcStoreID);
          } else {
              return copyContentBetweenStorageProviders(srcProvider,
                                                        srcSpaceID,
                                                        srcContentID,
                                                        srcStoreID,
                                                        destProvider,
                                                        destSpaceID,
                                                        destContentID,
                                                        destStoreID);
          }
      }
docs: This method copies the content found in space srcSpaceID with id
  srcContentID to the space destSpaceID within the same content store
  (storeID) to the id of destContentID.
  
  @param srcStoreID    of content to copy
  @param srcSpaceID    of content to copy
  @param srcContentID  of content to copy
  @param destSpaceID   of copied content
  @param destContentID of copied content
  @param destStoreID   of copied content
  @return MD5 checksum of the content as computed by the storage provider
  @throws ResourceException