資料結構與演算法(七)——二叉搜尋樹
阿新 • • 發佈:2020-12-18
新增MongoDB驅動
<dependency> <groupId>org.mongodb</groupId> <artifactId>mongo-java-driver</artifactId> <version>3.12.0</version> </dependency>
//連線 MongoDB MongoClient client=new MongoClient("localhost",27017); //連線資料庫 MongoDatabase database=client.getDatabase("test1"); System.out.println("connect success"); //建立集合 database.createCollection("test3"); //獲取集合 MongoCollection<Document> collection=database.getCollection("hjy"); /** * 插入文件,先建立文件,再插入 */ //建立文件,可以是map,可以是key-value System.out.println("insert document..."); Document document=new Document("title","mongodb") .append("description","database") .append("likes",5000) .append("by","hjy1"); List<Document> documents=new ArrayList<Document>(); documents.add(document); //插入單個文件用 insertOne collection.insertMany(documents); System.out.println("insert success..."); /** * 查詢所有文件 */ System.out.println("query all document..."); FindIterable<Document> findIterable=collection.find(); MongoCursor<Document> mongoCursor=findIterable.iterator(); while(mongoCursor.hasNext()){ System.out.println(mongoCursor.next()); } System.out.println("query all document success..."); /** *更新文件,更新likes=100的文件為likes=501 */ System.out.println("update document..."); collection.updateMany(Filters.eq("likes",100), new Document("$set",new Document("likes",501))); System.out.println("update success..."); /** * 刪除文件,刪除likes=1005的文件 */ System.out.println("delete document..."); collection.deleteOne(Filters.eq("likes",1005)); System.out.println("delete success..."); //關閉連線 client.close();