? 主要功能：對mongodb的集合做增刪改查。

? ? 項目的運行環境：tomcat6、jdk8。

? ? 所用技術：jsp/servlet、前端bootstrap。

? ? mongodb：personmap。

mongodb工具類：

? ??定義一個MongoDBUtil的枚舉類，枚舉類中定義一個instance實例。

??? MongoDB工具類 Mongo實例代表了一個數據庫連接池，即使在多線程的環境中，一個Mongo實例對我們來說已經足夠。
????注意Mongo已經實現了連接池，并且是線程安全的。
??? 設計為單例模式， 因 MongoDB的Java驅動是線程安全的，對于一般的應用，只要一個Mongo實例即可。
??? Mongo有個內置的連接池（默認為10個） 對于有大量寫和讀的環境中，為了確保在一個Session中使用同一個DB時，DB和DBCollection是絕對線程安全的

public enum MongoDBUtil {/*** 定義一個枚舉的元素，它代表此類的一個實例*/instance; } View Code

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? ? 在MongoDBUtil類中，定義一個MongoClient對象，并根據IP和端口獲得該對象。

private MongoClient mongoClient;static {System.out.println("===============MongoDBUtil初始化========================");// 從配置文件中獲取屬性值String ip = "localhost";int port = 27017;instance.mongoClient = new MongoClient(ip, port);} View Code

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? ? ?根據MongoClient對象，得到MongoDataBase對象和MongoConnection<Document>對象。

1 /** 2 * 獲取DB實例 - 指定DB 3 * 4 * @param dbName 5 * @return 6 */ 7 public MongoDatabase getDB(String dbName) { 8 if (dbName != null && !"".equals(dbName)) { 9 MongoDatabase database = mongoClient.getDatabase(dbName); 10 return database; 11 } 12 return null; 13 } 14 /** 15 * 獲取collection對象 - 指定Collection 16 * 17 * @param collName 18 * @return 19 */ 20 public MongoCollection<Document> getCollection(String dbName, String collName) { 21 if (null == collName || "".equals(collName)) { 22 return null; 23 } 24 if (null == dbName || "".equals(dbName)) { 25 return null; 26 } 27 MongoCollection<Document> collection = mongoClient.getDatabase(dbName).getCollection(collName); 28 return collection; 29 } View Code

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? ? ?工具類的查詢、插入、更新、刪除方法。

1 /**條件查詢*/ 2 public MongoCursor<Document> find(MongoCollection<Document> coll, Bson filter) { 3 if(null!=filter){ 4 return coll.find(filter).iterator(); 5 }else{ 6 return coll.find().iterator(); 7 } 8 } 9 /**插入一條數據*/ 10 public void insert(MongoCollection<Document> coll,Document doc){ 11 coll.insertOne(doc); 12 } 13 14 /**更新一條數據*/ 15 public void update(MongoCollection<Document> coll,Document querydoc,Document updatedoc){ 16 coll.updateMany(querydoc, updatedoc); 17 } 18 19 /**刪除一條數據*/ 20 public void delete(MongoCollection<Document> coll,Document doc){ 21 coll.deleteMany(doc); 22 } View Code

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?項目中的增刪改查：

? ? 插入：對應MongoDB中腳本的db.getCollection('person').insert({"name":"ryan1","age":21})

1 String name = request.getParameter("name"); 2 Double age = Double.valueOf(request.getParameter("age")); 3 4 String dbName = "personmap"; 5 String collName = "person"; 6 MongoCollection<Document> coll = MongoDBUtil.instance.getCollection(dbName, collName); 7 8 Document doc = new Document(); 9 doc.put("name", name); 10 doc.put("age", age); 11 MongoDBUtil.instance.insert(coll, doc); 12 13 PrintWriter out = response.getWriter(); 14 out.write("insert success!"); 15 16 插入功能的servlet View Code 1 <div class="panel panel-warning" style="width:20%"> 2 <div class="panel-heading">刪除文檔</div> 3 <div class="panel-body"> 4 <form action="InsertPerson"> 5 <input type="text" name="name" class="form-control" placeholder="name" aria-describedby="basic-addon1"> 6 <br/> 7 <input type="text" name="age" class="form-control" placeholder="age" aria-describedby="basic-addon1"> 8 <br/> 9 <button type="submit" class="btn btn-default">插入</button> 10 </form> 11 </div> 12 </div> 13 14 插入功能的jsp View Code

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? ? 更新：對應MongoDB中腳本的db.getCollection('person').update({"name":"ryan1"}{"$set":{"age":22}})

1 String queryname = request.getParameter("queryname"); 2 Double updateage = Double.valueOf(request.getParameter("updateage")); 3 4 String dbName = "personmap"; 5 String collName = "person"; 6 MongoCollection<Document> coll = MongoDBUtil.instance.getCollection(dbName, collName); 7 8 Document querydoc = new Document(); 9 querydoc.put("name", queryname); 10 11 Document updatedoc = new Document(); 12 updatedoc.put("name", queryname); 13 updatedoc.put("age", updateage); 14 15 MongoDBUtil.instance.update(coll, querydoc , new Document("$set",updatedoc)); 16 17 PrintWriter out = response.getWriter(); 18 out.write("update success!"); 19 20 更新功能的servlet View Code 1 <div class="panel panel-warning" style="width:20%"> 2 <div class="panel-heading">根據name更新age</div> 3 <div class="panel-body"> 4 <form action="UpdatePerson"> 5 <input type="text" name="queryname" class="form-control" placeholder="queryname" aria-describedby="basic-addon1"> 6 <br/> 7 <input type="text" name="updateage" class="form-control" placeholder="updateage" aria-describedby="basic-addon1"> 8 <br/> 9 <button type="submit" class="btn btn-default">更新</button> 10 </form> 11 </div> 12 </div> 13 14 更新功能的jsp View Code

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? ? 刪除：對應MongoDB中腳本的db.getCollection('person').remove({"name":"ryan1"})

1 String name = request.getParameter("name"); 2 3 String dbName = "personmap"; 4 String collName = "person"; 5 MongoCollection<Document> coll = MongoDBUtil.instance.getCollection(dbName, collName); 6 7 Document doc = new Document(); 8 doc.put("name", name); 9 10 MongoDBUtil.instance.delete(coll, doc); 11 12 PrintWriter out = response.getWriter(); 13 out.write("delete success!"); 14 15 刪除功能的servlet View Code 1 <div class="panel panel-warning" style="width:20%"> 2 <div class="panel-heading">刪除文檔</div> 3 <div class="panel-body"> 4 <form action="DeletePerson"> 5 <input type="text" name="name" class="form-control" placeholder="name" aria-describedby="basic-addon1"> 6 <br/> 7 <button type="submit" class="btn btn-default">刪除</button> 8 </form> 9 </div> 10 </div> 11 12 刪除功能的jsp View Code

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? ? 查找：對應MongoDB中腳本的db.getCollection('person').find({})

1 String dbName = "personmap"; 2 String collName = "person"; 3 MongoCollection<Document> coll = MongoDBUtil.instance.getCollection(dbName, collName); 4 5 List<Person> personList = new ArrayList<Person>(); 6 // 查詢所有 7 //Bson filter = Filters.eq("name", "ryan1"); 8 Bson filter = null; 9 MongoCursor<Document> cursor = MongoDBUtil.instance.find(coll, filter); 10 while(cursor.hasNext()){ 11 Document tempdoc = cursor.next(); 12 Person person = new Person(); 13 person.set_id(tempdoc.get("_id").toString()); 14 person.setName(tempdoc.get("name").toString()); 15 person.setAge(Double.valueOf(tempdoc.get("age").toString())); 16 personList.add(person); 17 } 18 19 Gson gson = new Gson(); 20 21 PrintWriter out = response.getWriter(); 22 out.write(gson.toJson(personList)); 23 24 查找功能的servlet View Code 1 <div class="panel panel-warning" style="width:50%"> 2 <div class="panel-heading">查找全部數據</div> 3 <div class="panel-body"> 4 <table data-toggle="table" 5 data-url="FindPerson" 6 data-classes="table table-hover table-condensed" 7 data-striped="true"> 8 <thead> 9 <tr> 10 <th class="col-xs-2" data-field="_id">_id</th> 11 <th class="col-xs-2" data-field="name">name</th> 12 <th class="col-xs-2" data-field="age">age</th> 13 </tr> 14 </thead> 15 </table> 16 </div> 17 </div> 18 19 查找功能的jsp View Code

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轉載于:https://www.cnblogs.com/bzmlving/p/5555470.html

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