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: ?4YGT
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CountBean.java IW5,7.
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/* `>o{P/HN
* CountData.java =F|{#F
* /'SNw?&
* Created on 2007年1月1日, 下午4:44 /WcG{Wdp
* !t"4!3
* To change this template, choose Tools | Options and locate the template under Z{*\S0^ST
* the Source Creation and Management node. Right-click the template and choose & l<.X
* Open. You can then make changes to the template in the Source Editor. YP oSRA L
*/ aj='b.2)
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package com.tot.count; ,~U>'&M;
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/** n9\TO9N
* G/E+L-N#`
* @author KYm0@O>;
*/ p
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public class CountBean { hE{K=Tz$
private String countType; <)Dj9' _J
int countId; X0HZH?V+
/** Creates a new instance of CountData */ hPB9@hT$
public CountBean() {} 70d 1ReQ
public void setCountType(String countTypes){ hgG9m[?K
this.countType=countTypes; :
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} 8S
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public void setCountId(int countIds){ 2k~l$p>CN!
this.countId=countIds; sI=xl
} AYBns]!
public String getCountType(){ #^0R&) T
return countType; VD*6g%p
} x8 2cT21b
public int getCountId(){ ~12EQacOT
return countId; 9cbd~mM{
} "Fr.fhh'~
} ~ah~cwmpS
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CountCache.java >58YjLXb
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/* DeVv4D:}@
* CountCache.java ),%%$G\
* K8|r&`X0
* Created on 2007年1月1日, 下午5:01 q>_.[+6
* XSB"{H>&
* To change this template, choose Tools | Options and locate the template under P8:dU(nlW
* the Source Creation and Management node. Right-click the template and choose $S6`}3
* Open. You can then make changes to the template in the Source Editor. s[>,X#7 y
*/ 7~h<$8Y(T
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package com.tot.count; -m zIT4
import java.util.*; +HpA:]#Y
/** QT5TE: D
* #lo6c;*m5
* @author =ZznFVJ`={
*/ 2QcOR4_V
public class CountCache { Evq IcZ
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ y-b%T|p9
public CountCache() {} 1s&zMWC
public static void add(CountBean cb){ z|J_b"u4
if(cb!=null){ WDYeOtc
list.add(cb); yWc$>ne[L
} tKuwpT1Qc
} "S]0
} X,%
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CountControl.java Dj?> <@
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/* ($MlX BI
* CountThread.java @gEUm_#HTs
* D/gw .XYL
* Created on 2007年1月1日, 下午4:57 .hb:s,0mP
* 5V~oIL
* To change this template, choose Tools | Options and locate the template under C
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* the Source Creation and Management node. Right-click the template and choose i^&~?2
* Open. You can then make changes to the template in the Source Editor. 79j+vH!zh
*/ p`dU2gV
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package com.tot.count; 6Pnjmw.HV
import tot.db.DBUtils; 1-uxC^u?|#
import java.sql.*; 76Cl\rV
/** &ywPuTt
* ~Ffo-Nd-
* @author s c,Hq\$&
*/ 4Z=_,#h4.
public class CountControl{ tS5hv@9cWx
private static long lastExecuteTime=0;//上次更新时间 `?rSlR@+[I
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 U}[d_f
/** Creates a new instance of CountThread */ bH9kj/q\b
public CountControl() {} |s(FLF -
public synchronized void executeUpdate(){ W\,s:6iqz
Connection conn=null; HWrO"b*tO
PreparedStatement ps=null; {]!mrAjD
try{ e]"W!KcD9
conn = DBUtils.getConnection(); {4}yKjW%z
conn.setAutoCommit(false); n,(sBOQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); X7MM2V
for(int i=0;i<CountCache.list.size();i++){ bo>*fNqAIy
CountBean cb=(CountBean)CountCache.list.getFirst(); Zn+.;o)E<
CountCache.list.removeFirst(); 4[r0G+
ps.setInt(1, cb.getCountId()); P )"m0Lu<
ps.executeUpdate();⑴ 2WL|wwA
//ps.addBatch();⑵ Fnv;^}\z
} x /S}Q8!"}
//int [] counts = ps.executeBatch();⑶ }'V5/>m[
conn.commit(); k,6f
}catch(Exception e){ %@aSe2B
e.printStackTrace(); "Yv_B3p
} finally{ .V/Rfq
try{
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if(ps!=null) { =[{i{x|Qz
ps.clearParameters(); Gr'
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ps.close(); bHYy }weZ
ps=null; 34O
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} @f~RdO3
}catch(SQLException e){} wE>\7a*P%
DBUtils.closeConnection(conn); iL&fgF"'
} 6r0krbN
} %D34/=(X
public long getLast(){ KeB"D!={;
return lastExecuteTime; TDKki(o=~
} BLdvyVFx
public void run(){ ]i)c{y
long now = System.currentTimeMillis(); }O5i/#.lR
if ((now - lastExecuteTime) > executeSep) { PI)+Jr%L
//System.out.print("lastExecuteTime:"+lastExecuteTime); (O?.)jEW(.
//System.out.print(" now:"+now+"\n"); d#Y^>"|$.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); rSk>
lastExecuteTime=now; 29"'K.r
executeUpdate(); Jb@V}Ul$
} X*XZb F"=
else{ ;O6;.5q&
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q#X8u-~
} ~s*)f.l
} :yr+vcD?
} Su7?;Oh/yI
//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 m|n%$$S&
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类写好了,下面是在JSP中如下调用。 =E4LRKn
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<% mt{nm[D!Xp
CountBean cb=new CountBean(); oy=js -
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =,=A,kI[;
CountCache.add(cb); x b~yM%*c
out.print(CountCache.list.size()+"<br>"); )e+>w=t
CountControl c=new CountControl(); Tod&&T'UW
c.run(); C.yQ=\U2
out.print(CountCache.list.size()+"<br>"); zuad~%D<I
%>