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: |UxG $M(
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CountBean.java E3iW-B8u8
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/* UQI]>#_/v
* CountData.java WpRc)g:
* PuZf/um
* Created on 2007年1月1日, 下午4:44 6<ZkJ:=
* o$Z6zm xO
* To change this template, choose Tools | Options and locate the template under b^$|Nz;
* the Source Creation and Management node. Right-click the template and choose n0e1k.A
* Open. You can then make changes to the template in the Source Editor. ]h5Yg/sms
*/ YS%h^>I^
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package com.tot.count; W0]gLw9*
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/** ZXuv CI
* %GS(:]{n
* @author XUlS\CH@{
*/ Uh):b%bS;J
public class CountBean { 9
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private String countType; a,WICv0E
int countId; L');!/:
/** Creates a new instance of CountData */ :d#VE-e
public CountBean() {} y;o^- O
public void setCountType(String countTypes){ &Ob!4+v/GP
this.countType=countTypes; $
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} q*7VqB
public void setCountId(int countIds){ 5w@4:$=I
this.countId=countIds; ] A+?EE2/
} d >t<_}
public String getCountType(){ I]EbodAyZ,
return countType; 07^iP>?
} C
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public int getCountId(){ ^i}
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return countId; yLQ*"sw\
} 2P@sn!*{1
} uvG]1m#
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CountCache.java 1jF`5k
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/* trp0V4b8
* CountCache.java ]n~ilS.rkl
* ~"kb7Fxp
* Created on 2007年1月1日, 下午5:01 Ot6aRk
* <t
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* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose D5*q7A6
* Open. You can then make changes to the template in the Source Editor. LB a[:j2
*/ ZGKu>yM
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package com.tot.count; !*%WuyCgr4
import java.util.*; 4k@5/5zsM
/** mh{1*T$fP
* -K3^BZHI
* @author n74V|b6W
*/ ='Y!+
public class CountCache { zp%Cr.)$
public static LinkedList list=new LinkedList(); c5D)
/** Creates a new instance of CountCache */ "$N+"3I
public CountCache() {} Gf<'WQ[
public static void add(CountBean cb){ .w8J*JZ
if(cb!=null){ r 0iK
list.add(cb); wlqpn(XR
} esMX-.8Cx
} ap+JQ@b
} s pp f
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CountControl.java X6@WwM~qz
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/* mSb#Nn6W
* CountThread.java Yd=>K HVD
* G'ei/Me6{
* Created on 2007年1月1日, 下午4:57 [Q/TlO t5
* ov_j4j>6P
* To change this template, choose Tools | Options and locate the template under [8=vv7wS
* the Source Creation and Management node. Right-click the template and choose )E-inHD /
* Open. You can then make changes to the template in the Source Editor. AN/;)wc
*/ :lPb.UCY
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package com.tot.count; U$WxHYo
import tot.db.DBUtils; K|hjEQRv
import java.sql.*; F|e1"PkeoA
/** #\ X#w<\?
* rp!oO>F
* @author 4hTMbS_;
*/ C,ARXW1
public class CountControl{ \1fN0e
private static long lastExecuteTime=0;//上次更新时间 hM6PP7XH
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 vnM@QfN
/** Creates a new instance of CountThread */ rPLm5ni
public CountControl() {} rLI8pA|.
public synchronized void executeUpdate(){ KmA;HiH%J
Connection conn=null; yl7&5)b#9
PreparedStatement ps=null; 0c<.iM
try{ ]dGw2y
conn = DBUtils.getConnection(); .ZVUd84B
conn.setAutoCommit(false); \%f q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); sP;nGQ.eN
for(int i=0;i<CountCache.list.size();i++){ QSszn`e
CountBean cb=(CountBean)CountCache.list.getFirst(); pgQV /6
CountCache.list.removeFirst(); 4GY[7^
ps.setInt(1, cb.getCountId()); Rld!,t
ps.executeUpdate();⑴ y)W@{@{kl
//ps.addBatch();⑵ %'s>QF]'
} D*gFV{Ws
//int [] counts = ps.executeBatch();⑶ ;U.hxh;+
conn.commit(); d(:8M
}catch(Exception e){ 4,CXJ2
e.printStackTrace(); }dWq=)*
} finally{ o7sT=x9
try{ ->y J5smtY
if(ps!=null) { }NzpiY9
ps.clearParameters(); ,^w?6?,&l}
ps.close(); iw8yb;|z;A
ps=null; UBaAx21x
} 0 yuW*z
}catch(SQLException e){} gy 3i+J
DBUtils.closeConnection(conn); rA5=dJ"I
} x7jC)M<k0
} X.f>'0i
public long getLast(){ O&4SCVZp
return lastExecuteTime; AP7Yuv`
} ]+XYEv
public void run(){ xp}hev^@$
long now = System.currentTimeMillis(); 2(u,SQ
if ((now - lastExecuteTime) > executeSep) { G IT>L
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y&d00
//System.out.print(" now:"+now+"\n"); WJkZ!O$"j
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4W#vP
lastExecuteTime=now; |Lf"6^@yh
executeUpdate(); rvbLyv;~
} @|63K)Xy
else{ BGD8w2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]
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} |"/8XA
} %_RQx2
} D#il*
//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 /H(?
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类写好了,下面是在JSP中如下调用。 %)|9E>fP]N
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<% %,6#2X nX%
CountBean cb=new CountBean(); Sa?ksD2IaB
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); g*e
CountCache.add(cb); 7hlO#PYZ
out.print(CountCache.list.size()+"<br>"); Jq&uF*!
CountControl c=new CountControl(); i|w81p^o
c.run(); (e!0]Io@
out.print(CountCache.list.size()+"<br>"); }Qip&IN
%>