FullEntity<IncompleteKey> incBookEntity = Entity.newBuilder(key)  // Create the Entity
.set(Book.AUTHOR, book.getAuthor())           // Add Property ("author", book.getAuthor())
.set(Book.DESCRIPTION, book.getDescription())
.set(Book.PUBLISHED_DATE, book.getPublishedDate())
.set(Book.TITLE, book.getTitle())
<BUG>.set(Book.IMAGE_URL, book.getImageUrl())
.build();</BUG>
Entity bookEntity = datastore.add(incBookEntity); // Save the Entity
return bookEntity.getKey().getId();                     // The ID of the Key
}

FullEntity<IncompleteKey> incBookEntity = Entity.newBuilder(key)  // Create the Entity
.set(Book.AUTHOR, book.getAuthor())           // Add Property ("author", book.getAuthor())
.set(Book.DESCRIPTION, book.getDescription())
.set(Book.PUBLISHED_DATE, book.getPublishedDate())
.set(Book.TITLE, book.getTitle())
.set(Book.IMAGE_URL, book.getImageUrl())
.set(Book.CREATED_BY, book.getCreatedBy())
.set(Book.CREATED_BY_ID, book.getCreatedById())
.build();
Entity bookEntity = datastore.add(incBookEntity); // Save the Entity
return bookEntity.getKey().getId();                     // The ID of the Key
}
