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: (#Y~z',I
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CountBean.java XE}gl&\
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/* ~MC|
* CountData.java k ut=(;
* ZZw`8 E
* Created on 2007年1月1日, 下午4:44 :xh{SsW@
* {Su?*M2y
* To change this template, choose Tools | Options and locate the template under N9e'jM>Oos
* the Source Creation and Management node. Right-click the template and choose "TV'}HH
* Open. You can then make changes to the template in the Source Editor. &`"DG$N(
*/ $*yYmF
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package com.tot.count; D'"
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/** $
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* p@m0Oi,=
* @author z:Ml;y
*/ qpjY &3SI
public class CountBean { O\5%IfB'"
private String countType; /k#-OXP~
int countId; g 9_ zkGc7
/** Creates a new instance of CountData */ dGIdSQ~ _
public CountBean() {} Rn1oD3w
public void setCountType(String countTypes){ .Ro/ioq
this.countType=countTypes; '%N?r,x
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} b+rxin".
public void setCountId(int countIds){ ,T/Gv;wa2
this.countId=countIds; jk AjYR .
} zTz}H*U
public String getCountType(){ hnnB4]c
return countType; 0Y.z
} Kl1v^3\{
public int getCountId(){ j#NyNv(jE1
return countId; @CMI$}!{V
} =~#mF<z5
} j{@O%fv=
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CountCache.java $%<{zWQm
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/* vB:\ZX4
* CountCache.java IpP%WW u
* @=-(H<0
* Created on 2007年1月1日, 下午5:01 P"YdB|I
* YW}$e W*
* To change this template, choose Tools | Options and locate the template under th?+TNb^
* the Source Creation and Management node. Right-click the template and choose {15j'Qwm
* Open. You can then make changes to the template in the Source Editor. vgfC{]v<W]
*/ BZq#OAp
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package com.tot.count; ({f}Z-%
import java.util.*; -'rdN i
/** X+hHE kJ
* Z%t_1t
* @author Ltlp9 S
*/ w:&""'E
public class CountCache { 2M
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public static LinkedList list=new LinkedList(); 7CIN!vrC|1
/** Creates a new instance of CountCache */ /x VHd
public CountCache() {} @CprC]X
public static void add(CountBean cb){ l45/$G7
if(cb!=null){ LUOjaX
list.add(cb); c4JV~VS+
} <2$vo
} y Zafq"o
} j\2Qe%d
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CountControl.java ?=u?u
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/* inP2y ?j
* CountThread.java c[dSO(=
* ,7{|90'V<
* Created on 2007年1月1日, 下午4:57 ~q$]iwwqT
* KX)n+{
* To change this template, choose Tools | Options and locate the template under M4^G3c<
* the Source Creation and Management node. Right-click the template and choose *"%TAe7?~+
* Open. You can then make changes to the template in the Source Editor. ]\,?u /
*/ {)YbksrJ{
v"*r %nCi
package com.tot.count; J_Lmy7~xbD
import tot.db.DBUtils; 7!O"k#
import java.sql.*; IH|zNg{\Y
/** TI>5g(:3\
* mF4W4~"
* @author 5ggyk0
*/ |v&)O)Jg
public class CountControl{ Jo? LPR
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private static long lastExecuteTime=0;//上次更新时间 VB |?S|<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %hB-$nE
/** Creates a new instance of CountThread */ %~rEJB@{
public CountControl() {} 3CCs_AO
public synchronized void executeUpdate(){ ah>c)1DA*H
Connection conn=null; \)PB p
PreparedStatement ps=null; v{u3[c
try{ Z8v\>@?5R
conn = DBUtils.getConnection(); L.n@;*
conn.setAutoCommit(false); ]'.qRTz'\t
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \CB^9-V3
for(int i=0;i<CountCache.list.size();i++){ !np_B0`
CountBean cb=(CountBean)CountCache.list.getFirst(); N$fP\h^AR
CountCache.list.removeFirst(); 'gwh:
ps.setInt(1, cb.getCountId()); T:^.; ZY
ps.executeUpdate();⑴ ak(s@@k
//ps.addBatch();⑵ |G j.E
} _@5Xmr
//int [] counts = ps.executeBatch();⑶
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conn.commit(); L+t
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}catch(Exception e){ ]U?nYppV
e.printStackTrace(); T(!1\ TB
} finally{ *zrT;jG
try{ m&)/>'W
if(ps!=null) { Dri6\/0
ps.clearParameters(); u[a-9^&g
ps.close(); I?T
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ps=null; {^]qaQ[5N
} UZdnsG7
}catch(SQLException e){} hf`y_H+\7
DBUtils.closeConnection(conn); WowKq0sn
} N,`@Q7
} h ldZA
public long getLast(){ xP8/1wd.
return lastExecuteTime; #MC#K{Xd
} &;Ncc,jb
public void run(){ O,$*`RZpx
long now = System.currentTimeMillis(); fB2ILRc
if ((now - lastExecuteTime) > executeSep) { d59rq<yI
//System.out.print("lastExecuteTime:"+lastExecuteTime); [P2>KQ\
//System.out.print(" now:"+now+"\n"); GT6; I7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;qmnG3;Q
lastExecuteTime=now; ;>,B(Xz4i
executeUpdate(); qq)5)S
} -Jv,#Z3
else{ NlYuT+
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ko%mZ0Y
} F|%PiC,,qO
} 5Tn<
} '5}hm1,
//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 ;~3;CijJ8
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类写好了,下面是在JSP中如下调用。 "8QRYV~Z
=!Ik5LiD
<% {i>AQ+z61f
CountBean cb=new CountBean(); _L,~WYRo
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); MN: {,#d0
CountCache.add(cb); #}Qe{4L
out.print(CountCache.list.size()+"<br>"); Dj/Hz\
CountControl c=new CountControl(); Df"PNUwA"
c.run(); w1Bkz\95
out.print(CountCache.list.size()+"<br>"); rCJ$Pl9R
%>