Java and MongoDB link for project

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鑒於開源項目的發展，大力擁抱開源社區。發現Java和MongoDB不失為一個較好的選擇。

與其他資料庫一樣，同樣需要mongo-java-driver，構建了Java與MongoDB的互動。

1. 串連MongoDB

1.1 普通資料庫的串連

MongoClient mongoClient = new MongoClient();

MongoClient mongoClient = new MongoClient( "localhost" );

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

MongoClient mongoClient = new MongoClient(Arrays.asList(new ServerAddress("localhost", 27017),new ServerAddress("localhost", 27018),new ServerAddress("localhost", 27019)));

1.2 有許可權要求的資料庫連接

MongoCredential credential = MongoCredential.createMongoCRCredential(userName, database, password);MongoClient mongoClient = new MongoClient(new ServerAddress(), Arrays.asList(credential));

2. 串連MongoDB具體資料庫

2.1 串連具體資料庫

DB db = mongoClient.getDB( "mydb" );

2.2 列印所有資料庫

List<String> dbs = mongoClient.getDatabaseNames();for (String db : dbs) {    System.out.println(db);}

3. 獲得資料庫中的具體一個集合

3.1 串連具體集合

DBCollection coll = db.getCollection("testCollection");

3.2 列印所有集合

Set<String> tables = db.getCollectionNames();for (String coll : tables) {    System.out.println(coll);}

4. 插入資料項目

BasicDBObject doc = new BasicDBObject("name", "MongoDB")        .append("type", "database")        .append("count", 1)        .append("info", new BasicDBObject("x", 203).append("y", 102));coll.insert(doc);

5. 查詢資料項目

5.1 查詢最新一個資料項目

DBObject myDoc = coll.findOne();System.out.println(myDoc);

5.2 查詢所有資料項目

DBCursor cursor = coll.find();try {   while(cursor.hasNext()) {       System.out.println(cursor.next());   }} finally {   cursor.close();}

5.3 查詢資料項目個數

System.out.println(coll.getCount());

5.4 查詢特定資料項目

5.4.1 等於某個條件

BasicDBObject query = new BasicDBObject("i", 71);cursor = coll.find(query);try {   while(cursor.hasNext()) {       System.out.println(cursor.next());   }} finally {   cursor.close();}

5.4.2 大於或者小於某個條件

// find all where i > 50query = new BasicDBObject("i", new BasicDBObject("$gt", 50));cursor = coll.find(query);try {    while (cursor.hasNext()) {        System.out.println(cursor.next());    }} finally {    cursor.close();}

6. 更新資料項目

DBCollection table = db.getCollection("user");BasicDBObject query = new BasicDBObject();query.put("name", "mkyong");BasicDBObject newDocument = new BasicDBObject();newDocument.put("name", "mkyong-updated"); BasicDBObject updateObj = new BasicDBObject();updateObj.put("$set", newDocument); table.update(query, updateObj);

7. 刪除資料項目

DBCollection table = db.getCollection("user");BasicDBObject searchQuery = new BasicDBObject();searchQuery.put("name", "mkyong"); table.remove(searchQuery);

 

Java and MongoDB link for project