有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: r Ljb'\<*
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CountBean.java KKCzq
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/* }.L\O]~{
* CountData.java -MCDX^>P
* !"G|y4O
* Created on 2007年1月1日, 下午4:44 o>#ue<Bc6
* e[>c>F^
* To change this template, choose Tools | Options and locate the template under ,4OH9-Q1
* the Source Creation and Management node. Right-click the template and choose Xf"B\%,(`
* Open. You can then make changes to the template in the Source Editor. M<%g )jn_
*/ [?=Vqd
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package com.tot.count; gf&\)"
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/** si!jB%^
* RqONVytx
* @author 1luRTI8^
*/ jNC@b>E?~
public class CountBean { A~!v+W%vO1
private String countType; q#6K'=AC
int countId; c9
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/** Creates a new instance of CountData */ ~vL`[JiK
public CountBean() {} /'ukeK+'
public void setCountType(String countTypes){ ,drcJ
this.countType=countTypes; wH<'*>/
} C<T)'^7z
public void setCountId(int countIds){ T1([P!g*
this.countId=countIds; i'\7P-a
} d~>d\K%v
public String getCountType(){ av!'UZP
return countType; #C`IfP./
} ,P T5-9 m
public int getCountId(){ l)d(N7HME
return countId; ;;Y>7Kn!u
}
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} QrX 5Kwq
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CountCache.java hk7kg/"
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/* j@98UZ{g\
* CountCache.java mjI
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* ^(:Z*+X~>
* Created on 2007年1月1日, 下午5:01 fPj*qi
* .Z2zv*
* To change this template, choose Tools | Options and locate the template under Wb;x
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* the Source Creation and Management node. Right-click the template and choose !L({i')
* Open. You can then make changes to the template in the Source Editor. 6%^9`|3
*/ WS7a]~3'
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package com.tot.count; y?}R,5k
import java.util.*; M#5*gWfq9
/** `Cv@16
* tw*n+{]hi
* @author |nu)=Ag
*/ ]CnqPLqL
public class CountCache { -IP 3I
public static LinkedList list=new LinkedList(); "AayU
/** Creates a new instance of CountCache */ <:YD.zAh|
public CountCache() {} G#f(oGn :
public static void add(CountBean cb){ fN-y8
if(cb!=null){ q]}1/JZS
list.add(cb); h{BO\^6x
} q_gsYb
} "{X_[
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CountControl.java 4pw:O^v
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/* OZc.Rtgc
* CountThread.java *9?T?S|^$F
* F#
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* Created on 2007年1月1日, 下午4:57 2{gd4Kt6.
* ;A3aUN;"I
* To change this template, choose Tools | Options and locate the template under \.AI;^)X@]
* the Source Creation and Management node. Right-click the template and choose B;6N.X(K
* Open. You can then make changes to the template in the Source Editor. Z,ZebS@yG
*/ ;=ci7IT'
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package com.tot.count; S^/:O.X)c,
import tot.db.DBUtils; DP-euz
import java.sql.*; FE[{*8
/** HHMv%H]M
* gvi]#|
* @author CNRiK;nQ
*/ lDd8dT-Q.
public class CountControl{ SB<09|2
private static long lastExecuteTime=0;//上次更新时间 UB7H`)C}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Dn9AOi!
/** Creates a new instance of CountThread */ IY=CTFQ8lm
public CountControl() {} rcyq+wY #
public synchronized void executeUpdate(){ MY$-D+#/`
Connection conn=null; GSh~j-C'
PreparedStatement ps=null; g'Id31r'
try{ Dqu][~oQ
conn = DBUtils.getConnection(); Jc74A=sT
conn.setAutoCommit(false); SA'c}gP
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |x ~<Dc>0*
for(int i=0;i<CountCache.list.size();i++){ a|s64+
CountBean cb=(CountBean)CountCache.list.getFirst(); m@W\Pic,j.
CountCache.list.removeFirst(); f|&ga'5g&
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ ~LKX2Q:S
//ps.addBatch();⑵ 6IQkP9P(
} + mqz)-x
//int [] counts = ps.executeBatch();⑶ Wz^M*=,
conn.commit(); ,7{}}l
}catch(Exception e){ bR*/d-v^
e.printStackTrace(); mI[$c"!BD
} finally{ ;%V%6:5
try{ a=!I(50
if(ps!=null) { = Nd&My
ps.clearParameters(); M\f1]L|8d
ps.close(); k\J 6WT
ps=null; &d8z`amP
} @A-^~LoP.
}catch(SQLException e){} \EC=#E(
DBUtils.closeConnection(conn); Gw;[maM!%`
} ;Npv 2yAab
} Q;3v ]h_
public long getLast(){ xg>AW Q
return lastExecuteTime; u,rieKYF
} h{sY5d'D
public void run(){ xzRs;AXOp
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { .$k2.-k
//System.out.print("lastExecuteTime:"+lastExecuteTime); MDo4{7
//System.out.print(" now:"+now+"\n"); !/},k"p6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8#S}.|"?F
lastExecuteTime=now; s|1BqoE
executeUpdate(); t[.wx.y&0
} d/Z258
else{ !Hk$ t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ;8G( l
} =>0+BD
} S4jt*]w5b
} "?lm`3W"
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 bwm?\l.A
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类写好了,下面是在JSP中如下调用。 ~4Gs\U:!Q
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<% 5G\CT&cQR
CountBean cb=new CountBean(); as{^~8B
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \rw/d5.
CountCache.add(cb); O@
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out.print(CountCache.list.size()+"<br>"); =.]>,N`C
CountControl c=new CountControl(); H9["ZRL,Q
c.run(); &tULSp@J
out.print(CountCache.list.size()+"<br>"); ::xH C4tw
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