To use MongoDB, you must properly design the document structure to meet specific requirements. For example, if a document is randomly selected and skip is used to skip a random document, no random key is added to the document. Then, a random number is used to query the document efficiently. The random key can also be indexed, which is more efficient. Reasonable choice and design. Importjava.net. Unknown
To use MongoDB, you must properly design the document structure to meet specific requirements. For example, if a document is randomly selected and skip is used to skip a random document, no random key is added to the document. Then, a random number is used to query the document efficiently. The random key can also be indexed, which is more efficient. Reasonable choice and design. Import java.net. Unknown
To use MongoDB, you must properly design the document structure to meet specific requirements. For example, if a document is randomly selected and skip is used to skip a random document, no random key is added to the document,
Then, a random number is used to query documents efficiently. random keys can also be used to add indexes, which is more efficient. Reasonable choice and design.
Import java.net. unknownHostException; import java. util. date; import java. util. list; import com. mongodb. basicDBList; import com. mongodb. basicDBObject; import com. mongodb. DB; import com. mongodb. DBCollection; import com. mongodb. DBCursor; import com. mongodb. DBObject; import com. mongodb. mongo; import com. mongodb. except exception; import com. nerd. mongo. config. configFactory;/*** MONGOS * @ author chenlongquan **/public class extends util {private final static ThreadLocal
Mongos = new ThreadLocal
(); Public static DB getdb () {return getMongos (). getDB (ConfigFactory. getmediaconfig (). getDb ();} public static Mongo getMongos () {Mongo mongo = mongos. get (); if (mongo = null) {try {mongo = new Mongo (ConfigFactory. getmediaconfig (). getIp (), ConfigFactory. getmediaconfig (). getPort (); mongos. set (mongo);} catch (UnknownHostException e) {e. printStackTrace ();} catch (except exception e) {e. printStackTrace () ;}} r Eturn mongo;} public static void close () {Mongo mongo = mongos. get (); if (mongo! = Null) {mongo. close (); mongos. remove () ;}}/*** get set (table) ** @ param collection */public static DBCollection getCollection (String collection) {return getdb (). getCollection (collection );}.................................. ....................
Next we can perform basic crud operations on mongodb based on the above.
For example:
/*** Insert ** @ param collection * @ param o insert **/public static void insert (String collection, DBObject o) {getCollection (collection ). insert (o);}/*** batch insert ** @ param collection * @ param list * List of inserts */public void insertBatch (String collection, list
List) {if (list = null | list. isEmpty () {return;} getCollection (collection). insert (list );}
Test cases:
insert("user1",new BasicDBObject().append("name", "admin3").append("type", "2").append("score", 70) .append("level", 2).append("inputTime", new Date().getTime()));
Tool usage:
/*** Delete ** @ param collection * @ param q * query condition */public void delete (String collection, DBObject q) {getCollection (collection ). remove (q);}/*** batch Delete ** @ param collection * @ param list * Delete condition List */public void deleteBatch (String collection, list
List) {if (list = null | list. isEmpty () {return;} for (int I = 0; I <list. size (); I ++) {getCollection (collection ). remove (list. get (I ));}} /*** update ** @ param collection * @ param q * query condition * @ param setFields * update object */public static void update (String collection, DBObject q, DBObject setFields) {getCollection (collection ). updateMulti (q, new BasicDBObject ("$ set", setFields);}/*** query all objects in the set ** @ param collection */public static List
FindAll (String collection) {return getCollection (collection ). find (). toArray ();}/*** query all objects in the Set in sequence ** @ param collection * dataset * @ param orderBy * sorting */public static List
FindAll (String collection, DBObject orderBy) {return getCollection (collection ). find (). sort (orderBy ). toArray ();}/*** search (returns an object) ** @ param collection * @ param q * query condition */public static DBObject findOne (String collection, DBObject q) {return getCollection (collection ). findOne (q);}/*** search (returns an object) ** @ param collection * @ param q * query condition * @ param fileds * returned field */public static DBObject findOne (String collection, DBObject q, DBObject fileds) {return getCollection (collection ). findOne (q, fileds);}/*** query the collection object by page, return a specific field ** @ param collection * @ param q * query condition * @ param fileds * return field * @ pageNo page n * @ perPageCount number of records per page */public static List
FindLess (String collection, DBObject q, DBObject fileds, int pageNo, int perPageCount) {return getCollection (collection ). find (q, fileds ). skip (pageNo-1) * perPageCount ). limit (perPageCount ). toArray ();}