MongoDB Java Driver 3.4操作

1. 導入jar包

   <dependency>
       <groupId>org.mongodb</groupId>
       <artifactId>mongo-java-driver</artifactId>
       <version>3.4.2</version>
   </dependency>
   

2. 連接MongoDB

   實例化一個沒有任何連接參數的MongoClient對象，可以連接到運行在本地主機的27017端口

   MongoClient mongoClient = new MongoClient();
   

   我們也可以連接到指定主機的27017端口

   MongoClient mongoClient = new MongoClient("localhost");
   

   指定主機和端口

   MongoClient mongoClient = new MongoClient("localhost", 27017);
   

   指定MongoClientURI

   MongoClient mongoClient = new MongoClient(new MongoClientURI("mongodb://localhost:27017"));
   

3. 獲得數據庫和集合

   連接到test庫

   MongoDatabase database = mongoClient.getDatabase("test");
   

   獲得users集合

   MongoCollection<Document> collection = database.getCollection("users");
   

4. 查詢文檔

   用來打印查詢結果

   Block<Document> printBlock = new Block<Document>() {
       @Override
       public void apply(Document document) {
           System.out.println(document.toJson());
       }
   };
   

   查詢所有文檔

   collection.find().forEach(printBlock);
   
   collection.find(new Document()).forEach(printBlock);
   

   復合查詢

   collection.find(eq("name", "sue")).forEach(printBlock); // 通過過濾器查詢
   
   collection.find(and(gte("age", 20), lt("age", 30), eq("type", 2))).forEach(printBlock); // 通過Filters 過濾
   
   collection.find(new Document("age", new Document("$gte", 20).append("$lt", 30)).append("type", 2)).forEach(printBlock); // 通過 filter document 過濾
   
   

   返回指定的查詢字段

   collection.find().projection(new Document("name", 1).append("age", 1).append("type", 1).append("_id", 0)).forEach(printBlock); // 通過.projection()指定返回的字段
   
   collection.find().projection(fields(include("name", "age", "type"), excludeId())).forEach(printBlock);  // 通過Projections類過濾
   
   

   排序

   collection.find().sort(Sorts.ascending("name")).forEach(printBlock);    // 通過.sort() Sorts類排序
   
   

5. 增加文檔

   插入一條數據

   Document document = new Document("name", "webb")
               .append("age", 24)
               .append("type", 1)
               .append("status", "A")
               .append("favorites", new Document("sports", "run").append("food", "photo"));
   
   collection.insertOne(document);   // 插入一條數據
       
   

   插入多條數據

   Document document2 = new Document("name", "lebo")
               .append("age", 24)
               .append("type", 1)
               .append("status", "A")
               .append("favorites", new Document("sports", "run").append("food", "photo"));
   
   List<Document> documents = new ArrayList<>();
   documents.add(document);
   documents.add(document2);
   collection.insertMany(documents); // 插入多條數據
   
   

6. 更新文檔

   修改單個文檔

   collection.updateOne(eq("name", "abc"), combine(set("age", 24), set("status", "B")));
   

   修改多個文檔

   collection.updateMany(eq("name", "webb"), combine(set("age", 23), set("type", 2)));
   

   如果upsert為true的話，沒有匹配到查詢條件，就會插入一條。

   collection.updateOne(eq("name", "wenboxu"), combine(set("age", 24)), new UpdateOptions().upsert(true));
   

   替換一條記錄

   collection.replaceOne(eq("name", "wenboxu"), new Document("age", "22").append("name", "wenboxu"));
   

7. 刪除文檔

   刪除單個文檔

   collection.deleteOne(eq("name", "webb"));
   

   刪除多個文檔

   collection.deleteMany(eq("age", 22));
   

   刪除所有文檔

   collection.deleteMany(new Document());