package com.me.Utils; import com.mongodb.BasicDBObject; import com.mongodb.MongoClient; import com.mongodb.client.FindIterable; import com.mongodb.client.MongoCollection; import com.mongodb.client.MongoCursor; import com.mongodb.client.MongoDatabase; import com.mongodb.client.model.Filters; import org.bson.Document; import java.util.ArrayList; import java.util.List; /** * @Auther: wzs * @Date: 2020/10/23 17:13 * @Description: */ public class MongoUtil { //获取连接 dbName 数据库名称 public static MongoDatabase getConn(String dbName){ try{ // 连接到 mongodb 服务 MongoClient mongoClient = new MongoClient( "hadoop102" , 27017 ); // 连接到数据库 MongoDatabase mongoDatabase = mongoClient.getDatabase(dbName); System.out.println("Connect to database successfully"); return mongoDatabase; }catch(Exception e){ System.err.println( e.getClass().getName() + ": " + e.getMessage() ); return null; } } //创建集合 (表) collectionName 表名 public static void createCollection(String dbName,String collectionName){ MongoDatabase conn = getConn(dbName); conn.createCollection(collectionName); System.out.println("集合创建成功"); } //获取集合 public static MongoCollection<Document> getCollection(String dbName,String collectionName){ MongoDatabase conn = getConn(dbName); MongoCollection<Document> collection = conn.getCollection(collectionName); System.out.println("集合 test 选择成功"); return collection; } //插入集合 public static void insertCollection(String dbName,String collectionName,Document document){ MongoCollection<Document> collection = getCollection(dbName, collectionName); //插入文档 /** * 1. 创建文档 org.bson.Document 参数为key-value的格式 * 2. 创建文档集合List<Document> * 3. 将文档集合插入数据库集合中 mongoCollection.insertMany(List<Document>) 插入单个文档可以用 mongoCollection.insertOne(Document) * */ // Document document = new Document("title", "MongoDB"). // append("description", "database"). // append("likes", 100). // append("by", "Fly"); List<Document> documents = new ArrayList<Document>(); documents.add(document); collection.insertMany(documents); System.out.println("文档插入成功"); } //插入集合(多条) public static void insertCollection_(String dbName,String collectionName,List<Document> documents){ MongoCollection<Document> collection = getCollection(dbName, collectionName); collection.insertMany(documents); System.out.println("多条文档插入成功"); } //检索文档 all public static void selectCollection(String dbName,String collectionName){ MongoCollection<Document> collection = getCollection(dbName, collectionName); //检索所有文档 /** * 1. 获取迭代器FindIterable<Document> * 2. 获取游标MongoCursor<Document> * 3. 通过游标遍历检索出的文档集合 * */ FindIterable<Document> findIterable = collection.find(); MongoCursor<Document> mongoCursor = findIterable.iterator(); while(mongoCursor.hasNext()){ System.out.println(mongoCursor.next()); } } //检索文档 all public static void selectCollection(String dbName, String collectionName, BasicDBObject basicDBObject,BasicDBObject basicDBObjectH){ MongoCollection<Document> collection = getCollection(dbName, collectionName); //检索所有文档 /** * 1. 获取迭代器FindIterable<Document> * 2. 获取游标MongoCursor<Document> * 3. 通过游标遍历检索出的文档集合 * */ FindIterable<Document> findIterable = collection.find(basicDBObject).projection(basicDBObjectH); MongoCursor<Document> mongoCursor = findIterable.iterator(); while(mongoCursor.hasNext()){ System.out.println(mongoCursor.next()); } } //更新文档 public static void updateCollection(String dbName,String collectionName){ MongoCollection<Document> collection = getCollection(dbName, collectionName); //更新文档 将文档中likes=100的文档修改为likes=200 collection.updateMany(Filters.eq("likes", 100), new Document("$set",new Document("likes",200))); } //删除文档 public static void deleteCollection(String dbName,String collectionName){ MongoCollection<Document> collection = getCollection(dbName, collectionName); //删除符合条件的第一个文档 collection.deleteOne(Filters.eq("likes", 200)); //删除所有符合条件的文档 collection.deleteMany (Filters.eq("likes", 200)); } public static void main(String[] args) { BasicDBObject basicDBObject = new BasicDBObject("name", "zhangsan"); BasicDBObject basicDBObject2 = new BasicDBObject("name",0); selectCollection("student","student",basicDBObject,basicDBObject2); } }