使用java将数据插入mongodb

Question

我正在尝试使用 java 将数据插入 MongoDB，但在尝试编译代码时出现错误。我不知道是什么导致了错误。我想添加新书条目。error message: required: String,Object  found: List<Document>  reason: actual and formal argument lists differ in lengthUseMongoDB.java:61: error: method put in class Document cannot be applied to given types;book.put(publishers);private MongoCollection<Document> books = db.getCollection("books");  void insertanewbook() {            Document book = new Document();    book.put("title", "test");          book.put("category","test");                book.put("price",12.3);                List<Document> authors = new ArrayList<Document>();    Document author = new Document();                author.put("first_name","jonn");                author.put("last_name","james");                author.put("country","t");                author.put("website","www.test.com");    authors.add(author);    book.put(authors);    List<Document> publishers = new ArrayList<Document>();    Document publisher = new Document();                publisher.put("publish_date",new Date());                publisher.put("name","test");                publisher.put("country","test");    publisher.put("website","www.test.com");    publishers.add(publisher);    book.put(publishers);                    books.insertOne(book);  }

Answer 1

从您发布的错误消息...

reason: actual and formal argument lists differ in length

换句话说，方法put需要两个参数，而您只提供一个。从您发布的代码中，您缺少对方法调用的关键put()。只需添加相关密钥，例如

book.put("publishers", publishers);