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: 7f3,czW
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CountBean.java #|+4 `Gf^
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/* D9;pjY
* CountData.java vC1fKo\p
* L9^M?.a
* Created on 2007年1月1日, 下午4:44 * BrGh
* izcjI.3e,
* To change this template, choose Tools | Options and locate the template under [QMN0#(h
* the Source Creation and Management node. Right-click the template and choose @x*xgf
* Open. You can then make changes to the template in the Source Editor. {m3#1iV9
*/ J:'_S `J
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package com.tot.count; m<#^c?u
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/** G3y8M|:
* o=!_.lDF:
* @author %R?WkG
*/ &=S:I!9;;
public class CountBean { `, ]ui*
private String countType; 1D)0\#><
int countId; hMz)l\0
/** Creates a new instance of CountData */ &2.DZ),L
public CountBean() {} z{
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public void setCountType(String countTypes){ K2Ro0
this.countType=countTypes;
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}
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public void setCountId(int countIds){ y5*zyd
this.countId=countIds; &Qv HjjQ?u
} (#6Fg|f4Y
public String getCountType(){ xR$T/] /
return countType; _U LzA
} [f {qb\
public int getCountId(){ 9D`K#3}
return countId; x'?p?u~[
} 2[=3-1c
} "~.4z,ha
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CountCache.java Wj!+
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/* $8(QBZq
* CountCache.java %2b^t*CQ
* )l!
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* Created on 2007年1月1日, 下午5:01 u^MRKLn
* 0#=xUk#LP`
* To change this template, choose Tools | Options and locate the template under 7f
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* the Source Creation and Management node. Right-click the template and choose ~a4Y8r
* Open. You can then make changes to the template in the Source Editor. ex`T9j.=B
*/ ~uq010lMno
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package com.tot.count; }%PK %/ zI
import java.util.*; o_b3G
/** rZ n@i
* >r\GB#\5
* @author
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*/ $aU.M3
public class CountCache { JvvN>bg
public static LinkedList list=new LinkedList(); j[R.UB3J
/** Creates a new instance of CountCache */ F7j/Zuj
public CountCache() {} tw.GBR
public static void add(CountBean cb){ *aS+XnT/
if(cb!=null){ jTg~]PQ^
list.add(cb); 5_](N$$
} d^M*%a z
} 1anh@T.
} 479X5Cl
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CountControl.java 2z#S|$
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/* )qMbk7:v\
* CountThread.java opm_|0
* ?aWVfX!+G5
* Created on 2007年1月1日, 下午4:57 EFx>Hu/[G
* 'nM4t
* To change this template, choose Tools | Options and locate the template under Ye$j43b
* the Source Creation and Management node. Right-click the template and choose sCt)Yp+8}B
* Open. You can then make changes to the template in the Source Editor. 9M($_2,44
*/ :2M&C+f[
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package com.tot.count; *U%3[6hm
import tot.db.DBUtils; H#V&5|K%
import java.sql.*; vR!g1gI23
/** Wq+GlB*
* yZ[g2*1L
* @author N>*+Wg$Ne
*/ #\=7A
public class CountControl{ _A!Fp0}`
private static long lastExecuteTime=0;//上次更新时间 JN9>nC!Zy_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6|B9kh}
/** Creates a new instance of CountThread */ 1,)
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public CountControl() {} 8TAJ#Lm
public synchronized void executeUpdate(){ <B0f
Connection conn=null; Xj{fM\,"9
PreparedStatement ps=null; R{bG`C8.d
try{ GrJLQO0$N
conn = DBUtils.getConnection(); &V~l(1
conn.setAutoCommit(false); g<;::'6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,e9M%VIu6[
for(int i=0;i<CountCache.list.size();i++){ IaSpF<&Y;
CountBean cb=(CountBean)CountCache.list.getFirst(); 2'- "&d+O
CountCache.list.removeFirst(); d,l?{Ln
ps.setInt(1, cb.getCountId()); *5k40?w
ps.executeUpdate();⑴ ]OdZlZBsJ
//ps.addBatch();⑵ Q0K$ZWM`7
} .?QYqGcG
//int [] counts = ps.executeBatch();⑶ dTK0lgkUE
conn.commit(); $fg@g7_:
}catch(Exception e){ 8Vj'&UY
e.printStackTrace(); 7p2xst
} finally{ :EQ{7Op`
try{ 7_ayn#;y
if(ps!=null) { p)iEwl}!j
ps.clearParameters(); MomHSv Q\
ps.close(); 7p Y :.iVO
ps=null; `ROHB@-
} #I453
}catch(SQLException e){} w5%i
DBUtils.closeConnection(conn); =HsE:@
} Q*%}w_D6f
} kUS]g
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public long getLast(){ 2 HQ3G~U
return lastExecuteTime; LYRpd
} HBOyiIm Q
public void run(){ D%yY&q;
long now = System.currentTimeMillis(); bz#]>RD
if ((now - lastExecuteTime) > executeSep) { =iKl<CqI$E
//System.out.print("lastExecuteTime:"+lastExecuteTime); cXqYO|3/M
//System.out.print(" now:"+now+"\n"); C[
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); KsOWTq"uj
lastExecuteTime=now;
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executeUpdate(); JJtx `@Bc
} yTd8)zWq
else{ L0!CHP/nRS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W!? h2[
} Qw'905;(
} \*e\MOp6
} BXYH&2]Q
//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 Wj(#!\ 7F
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类写好了,下面是在JSP中如下调用。 }/vW"&h-
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<% I6f/+;E
CountBean cb=new CountBean(); b),fz
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3*=0`}jMJ
CountCache.add(cb); aU_Hl+;
out.print(CountCache.list.size()+"<br>"); LO{Axf%
CountControl c=new CountControl(); PZusYeV8b
c.run(); *l+Dbm,u
out.print(CountCache.list.size()+"<br>"); + tMf&BZ
%>