通过Java向Mongo集合中的每个文档添加新字段

import com.mongodb.MongoClient;
import com.mongodb.MongoException;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;

public class AddFieldToMongoDocument {
    public static void main(String[] args) {
        // 连接MongoDB数据库
        MongoClient mongoClient = new MongoClient("localhost", 27017);
        MongoDatabase database = mongoClient.getDatabase("mydb");
        MongoCollection<Document> collection = database.getCollection("mycollection");

        // 添加新字段
        Document newField = new Document("newField", "newFieldValue");

        try {
            // 更新每个文档
            collection.updateMany(new Document(), new Document("$set", newField));
            System.out.println("新字段添加成功！");
        } catch (MongoException e) {
            System.out.println("新字段添加失败：" + e.getMessage());
        }

        // 关闭连接
        mongoClient.close();
    }
}