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AskSQLTeam
Ask SQLTeam Question
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 Posted - 2004-05-03 : 10:28:53
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| jacky writes "I use connection pool from the ms's jdbc driver.But i found every time i want to use the connection, the programm always create a new connetion, instead of fetch the connection from the pool. There are many query need to do, so it used up the resource of db server and the client. Even i set the pool size is 2500, it can't work out!what's the problem of it?Thx a lot!//start of the codepackage kwe.util ;import java.io.* ;import java.sql.* ;import java.util.* ;import java.util.Date ;import kwe.db.*;/** * ¹ÜÀíÀàSqlServerÖ§³Ö¶ÔÒ»¸ö»ò¶à¸öÓÉÊôÐÔÎļþ¶¨ÒåµÄÊý¾Ý¿ Á¬½Ó * ³ØµÄ·ÃÎÊ.¿Í»§³ÌÐò¿ÉÒÔµ÷ÓÃgetInstance()·½·¨·ÃÎʱ¾ÀàµÄΨһʵÀý. */public class SqlServer{ static private SqlServer instance ; // ΨһʵÀý static private int clients ; private Vector drivers = new Vector() ; private PrintWriter log ; private Hashtable pools = new Hashtable() ; //cuiqi add the cache --2003-12-22 private HashMap cachedValueHash = new HashMap(); private HashMap cachedUnitCDHash = new HashMap(); private HashMap cachedUnitInfo = new HashMap(); //end of add //add for new arrival -- 2003-12-26 private Vector newArrivals = new Vector(); //add for domestic logistic temp worker -- 2003-01-05 private Vector logisticTemps = new Vector(); //add for store all who have year bonus -- 2004-01-06 private Vector yearBonusTable = new Vector(); private Vector outerManTable = new Vector(); private HashMap cachedOuterBonusHash = new HashMap(); private Vector foreignerTable = new Vector(); //end of add -- 2004-01-06 //add for cache 2004-01-08 private String salaryListCD; /** * ·µ»ØΨһʵÀý.Èç¹ûÊǵÚÒ»´Îµ÷Óô˷½·¨,Ôò´´½¨ÊµÀý * * @return SqlServer ΨһʵÀý */ static synchronized public SqlServer getInstance(String dateYM) { if(instance == null) { instance = new SqlServer(dateYM) ; } clients++ ; return instance ; } /** * ½¨¹¹º¯Êý˽ÓÐÒÔ·ÀÖ¹ÆäËü¶Ô¡¦´´½¨±¾ÀàʵÀý * Note: add the para "dateYM" to make the new arrival visible to sqlserver --2003-12-26 */ private SqlServer(String dateYM) { init(dateYM) ; }/** * ½«Á¬½Ó¶Ô¡¦·µ»Ø¸øÓÉÃû×ÖÖ¸¶¨µÄÁ¬½Ó³Ø * * @param name ÔÚÊôÐÔÎļþÖж¨ÒåµÄÁ¬½Ó³ØÃû×Ö * @param con Á¬½Ó¶Ô¡¦ */ public void freeConnection(String name,Connection con) { DBConnectionPool pool = (DBConnectionPool)pools.get(name) ; if(pool != null) { pool.freeConnection(con) ; //kwe.System.out.println("free connection ok"); } }/** * »ñµÃÒ»¸ö¿ÉÓõÄ(¿ÕÏеÄ)Á¬½Ó.Èç¹ûûÓпÉÓÃÁ¬½Ó,ÇÒÒÑÓÐÁ¬½ÓÊýСÓÚ×î´óÁ¬½ÓÊý * ¡¦ÖÆ,Ôò´´½¨²¢·µ»ØÐ Á¬½Ó * * @param name ÔÚÊôÐÔÎļþÖж¨ÒåµÄÁ¬½Ó³ØÃû×Ö * @return Connection ¿ÉÓÃÁ¬½Ó»ònull */ public Connection getConnection(String name) { DBConnectionPool pool = (DBConnectionPool)pools.get(name) ; if(pool != null) { return pool.getConnection() ; } return null ; }/** * »ñµÃÒ»¸ö¿ÉÓÃÁ¬½Ó.ÈôûÓпÉÓÃÁ¬½Ó,ÇÒÒÑÓÐÁ¬½ÓÊýСÓÚ×î´óÁ¬½ÓÊý¡¦ÖÆ, * Ôò´´½¨²¢·µ»ØÐ Á¬½Ó.·ñÔò,ÔÚÖ¸¶¨µÄʱ¼äÄڵȴýÆäËü¡¦³ÌÊÍ· |
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why the jdbc connection pool always try to create a new connection to the DB server?