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: u05Yy&(f
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CountBean.java .{} 8mFi1
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/* i];P!Gm
* CountData.java @BF1X.4-+
* j<k6z
* Created on 2007年1月1日, 下午4:44 Poa&htxe1
* py+\e"s
* To change this template, choose Tools | Options and locate the template under y@It#!u0
* the Source Creation and Management node. Right-click the template and choose 7nFOVZ
* Open. You can then make changes to the template in the Source Editor. /
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*/ %:zu68Q[
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package com.tot.count; P^48]Kj7
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/** N5h9){Mx
* z|X6\8f
* @author o. ;Vrc
*/ &i.sSqSI5
public class CountBean { 7GWOJ^)
private String countType; 7CvBE;i
int countId; Qh(X7B
/** Creates a new instance of CountData */ RtzSe$O
public CountBean() {} PP>6
public void setCountType(String countTypes){ LO>42o?/i
this.countType=countTypes; %dv?n#Uf
} M
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public void setCountId(int countIds){ $(Mz@#%
this.countId=countIds; F=
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} ?Ve IlD
public String getCountType(){ GNe^~
return countType; dRnf
} n P]!{J]
public int getCountId(){ _lFw1pa#\
return countId; ]z/R?SM
} I
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} Z0m`%(MJa
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CountCache.java v{fcQb
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/* y& 1@d+Lf
* CountCache.java nS*Y+Q^9a
* \ "$$c
* Created on 2007年1月1日, 下午5:01 OTdijQLY
* AyOibnoZ2E
* To change this template, choose Tools | Options and locate the template under s&(;
* the Source Creation and Management node. Right-click the template and choose 9|#cjHf
* Open. You can then make changes to the template in the Source Editor. kuV7nsXiQ
*/ ~IS8DW$;
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package com.tot.count; |=m.eU
import java.util.*; 9S*"={}%
/** Mjy:k|aY"
* T?t/[iuHrj
* @author >[,eK=
*/ ?'9IgT[*
public class CountCache { ~~Ezt*lH
public static LinkedList list=new LinkedList(); +ovK~K$A
/** Creates a new instance of CountCache */ *^~
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public CountCache() {} (Y@T5-!D
public static void add(CountBean cb){ $?G@ijk,
if(cb!=null){ ElV!C}g
list.add(cb); 5;U Iz@BJ
} "8{A4N1B5
} q1( [mHZ
} O9(z"c
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CountControl.java Kbf(P95+uL
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/* Q>Zc
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* CountThread.java ^hmV?a:Y
* _wS=*-fT
* Created on 2007年1月1日, 下午4:57 (^m]
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* Mzp<s<BX
* To change this template, choose Tools | Options and locate the template under 7MLLx#U
* the Source Creation and Management node. Right-click the template and choose [ 49Cvde^
* Open. You can then make changes to the template in the Source Editor. YcN|L&R.
*/ E,}{ iqAb
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package com.tot.count; . : Wf>:
import tot.db.DBUtils;
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import java.sql.*; uK2HtRY1
/** {E:`
* gM\>{ihM'
* @author D=TS IJ@
*/ SG&,o=I$
public class CountControl{ Og/aTR<;=
private static long lastExecuteTime=0;//上次更新时间 $`E?=L`$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q[,p#uJ]
/** Creates a new instance of CountThread */ &uK(. @
public CountControl() {} 6*q1%rs:w
public synchronized void executeUpdate(){ Q=`yPK>{$N
Connection conn=null; ;7QXs39S
PreparedStatement ps=null; l<f9$l^U
try{ 0\P5=hD)K
conn = DBUtils.getConnection(); >.d/@3
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conn.setAutoCommit(false); o$sD9xx
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %o0b~R
for(int i=0;i<CountCache.list.size();i++){ nn_O"fZi
CountBean cb=(CountBean)CountCache.list.getFirst(); ]?tRO
CountCache.list.removeFirst(); -WlYHW
ps.setInt(1, cb.getCountId()); +[!S[KE
ps.executeUpdate();⑴ )8@-
//ps.addBatch();⑵ j Q5 F}
} mH&7{2r
//int [] counts = ps.executeBatch();⑶ r ;RYGLx
conn.commit(); 4,I,f>V
}catch(Exception e){ c>_ti+
e.printStackTrace(); )S g6B;CJ
} finally{ <l{oE?N
try{ k&ci5MpN
if(ps!=null) { ES~b f
ps.clearParameters(); u}[ a
ps.close(); d_yvG.#C
ps=null; aDF@AS
} P}v
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}catch(SQLException e){} u2 s
DBUtils.closeConnection(conn); pAE
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} h;gc5"mG
} {aY) Qv}
public long getLast(){ _ ;j1g%
return lastExecuteTime; 8tx*z"2S
} N PT-d
public void run(){ DM^0[3XuV5
long now = System.currentTimeMillis(); tYu<(Z(l)
if ((now - lastExecuteTime) > executeSep) { 'x*C#mt
//System.out.print("lastExecuteTime:"+lastExecuteTime); bY" zK',m
//System.out.print(" now:"+now+"\n"); xsZG(Tz
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x77L"5g
lastExecuteTime=now; 2/&=:,"t,B
executeUpdate(); )QE6X67i
} r&]XNq'P9
else{ Qn*l,Z]US
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -V/y~/]J
} _z@/~M(
} NfV|c~?d
} MzIDeZ
//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 EN!C5/M{&
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类写好了,下面是在JSP中如下调用。 qVC+q8
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<% 8RMM97@1Q
CountBean cb=new CountBean(); r3'J{-kl
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); r%U6,7d=)
CountCache.add(cb); {r_HcI(h
out.print(CountCache.list.size()+"<br>"); |[?Otv
CountControl c=new CountControl(); ;g0Q_F@;p
c.run(); Q,3kaR@O
out.print(CountCache.list.size()+"<br>"); ~
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%>