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: E&U_@ bc-
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CountBean.java m@0> =s~.
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/* ziM@@$.F
* CountData.java kmtkh"
* Z5EII[=$o
* Created on 2007年1月1日, 下午4:44 !67xN?b
* R|wS*xd ,
* To change this template, choose Tools | Options and locate the template under f;Ijl 0d@
* the Source Creation and Management node. Right-click the template and choose pr,1pqiAf
* Open. You can then make changes to the template in the Source Editor. /;E=)(w
*/ :_,3")-v
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package com.tot.count; /~c9'38
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/** F}1._I`-
* v#: ?:<
* @author hb)C"q=
*/ %[azMlp<
public class CountBean { K*4ib/'E a
private String countType; *Ue#Sade
int countId; NGO?K?
/** Creates a new instance of CountData */ 8qxZ7|Y@
public CountBean() {} |Z+qaq{X
public void setCountType(String countTypes){ r>CBp$
this.countType=countTypes; aMJ2bu
} Xh/BVg7$
public void setCountId(int countIds){ \pSRG=`
this.countId=countIds; (*V!V3E3#
} ]6O(r)k
public String getCountType(){ (<}?}{YX0
return countType; L&uPNcZ`-
} 0I2?fz)
public int getCountId(){ S?VKzVDB.S
return countId; ocp
} BJ
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} 5D
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CountCache.java zTi
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/* jX*gw6!
* CountCache.java :7(d6gEL
* 2^:iU{
* Created on 2007年1月1日, 下午5:01 |tTcJ\bG
* +OtD@lD`!
* To change this template, choose Tools | Options and locate the template under 7;]IlR6
* the Source Creation and Management node. Right-click the template and choose M8y|Lm}o
* Open. You can then make changes to the template in the Source Editor. 1(%6X*z
*/ Ub4)x
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package com.tot.count; \]\ h,Y8
import java.util.*; lE8_Q *ev
/** 7vI
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* @author #'RfwldD9
*/ )M(//jX
public class CountCache { b!nA.`T
public static LinkedList list=new LinkedList(); ~*Y/#kPY
/** Creates a new instance of CountCache */ niYD[Ra\xP
public CountCache() {} $v"CQD
public static void add(CountBean cb){ wi[FBLB/8
if(cb!=null){ ,JPDPI/a
list.add(cb); (#>Q#Izr
} _)4zm
} BIg2`95F|
} x@pzgqi3
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CountControl.java mJH4M9WJ]
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/* + EKp*Vje
* CountThread.java 6{fo.M?
* z(>:LX"xz
* Created on 2007年1月1日, 下午4:57 <7/7+_y
* &._Mh
* To change this template, choose Tools | Options and locate the template under Kf)$/W4
* the Source Creation and Management node. Right-click the template and choose BrZ17
* Open. You can then make changes to the template in the Source Editor. Q^?$2ck=
*/ {?X +Yw
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package com.tot.count; Z 8GIZ
import tot.db.DBUtils; w[EEA_\
import java.sql.*; n-<`Z NMU
/** T ~p>Ed 9
* NvpDi&i
* @author $d&7q5[
*/ y\dx \
public class CountControl{ &hZ6CV{
private static long lastExecuteTime=0;//上次更新时间 "39mhX2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~uB@o KMru
/** Creates a new instance of CountThread */ \rS-}DG
public CountControl() {} m+ #G*
public synchronized void executeUpdate(){ wGHVq
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Connection conn=null; z@jKzyq
PreparedStatement ps=null; xZloEfv.B
try{ Dr}elR>~G=
conn = DBUtils.getConnection(); B>cx[.#!
conn.setAutoCommit(false); \D#+0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xq%BR[1
for(int i=0;i<CountCache.list.size();i++){ =Fq{#sC>
CountBean cb=(CountBean)CountCache.list.getFirst(); 4r7aZDVA\
CountCache.list.removeFirst(); OXX D}-t
ps.setInt(1, cb.getCountId()); =2}bQW
ps.executeUpdate();⑴ hWbjA[a/
//ps.addBatch();⑵ B\;fC's+
} *;lb<uLv
//int [] counts = ps.executeBatch();⑶ iA'p!l|P
conn.commit(); 'p%w_VbI
}catch(Exception e){ =H}}dC<)
e.printStackTrace(); YC*`n3D|'
} finally{ DnF|wS
try{ -YipPo"a
if(ps!=null) { 0-d&R@lX.
ps.clearParameters(); 1d&Q
E\2}
ps.close(); gDH|I;!
ps=null; C"k]U[%{
} 5yroi@KT
}catch(SQLException e){} e)F_zX
DBUtils.closeConnection(conn); KT<N
;[;
} ItAC=/(d
} w7<4D,hk
public long getLast(){ V:AA{<
return lastExecuteTime; ^[2siG
} sq8O+AWl
public void run(){ =[gFaB_H
long now = System.currentTimeMillis(); dcE(uf
if ((now - lastExecuteTime) > executeSep) { `_J>R
//System.out.print("lastExecuteTime:"+lastExecuteTime); q1/ mp){
//System.out.print(" now:"+now+"\n"); ;Z,l};b
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); MA7&fNjB
lastExecuteTime=now; ~AF'
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executeUpdate(); T7M];@q
} obgO-d9l
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X:
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} Maiy d
} a]I~.$G
} SMQC/t]HT
//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 of`WP
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类写好了,下面是在JSP中如下调用。 yv> 6u7
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<% g{m~TVm'
CountBean cb=new CountBean(); X(C=O?A
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8BnsYy)j
CountCache.add(cb); YsRq.9Mr
out.print(CountCache.list.size()+"<br>"); /T 4GPi\lg
CountControl c=new CountControl(); VB4ir\nF
c.run(); `3dGn.M
out.print(CountCache.list.size()+"<br>"); EDA6b]
%>