code: public void BasicUpsert() throws StorageException {
          // Retrieve the entity with partition key of "Smith" and row key of
          // "Jeff".
          TableOperation retrieveSmithJeff = TableOperation.retrieve("Smith",
                  "Jeff", CustomerEntity.class);
  
          // Submit the operation to the table service and get the specific
          // entity.
          CustomerEntity specificEntity = table.execute(retrieveSmithJeff)
                  .getResultAsType();
  
          // Specify a new phone number.
          specificEntity.setPhoneNumber("425-555-0105");
  
          // Create an operation to replace the entity.
          TableOperation replaceEntity = TableOperation.merge(specificEntity);
  
          // Submit the operation to the table service.
          table.execute(replaceEntity);
      }
docs: Illustrates how to form and execute an upsert operation.
  
  @throws StorageException