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: ynU20g
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CountBean.java *MZa|Xy
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/* ~SR9*<
* CountData.java [mA\,ny9
* h!q_''*;
* Created on 2007年1月1日, 下午4:44 db5@+_
* QK@[b3-h1
* To change this template, choose Tools | Options and locate the template under DNy 6Kw
* the Source Creation and Management node. Right-click the template and choose VJ()sbl{k
* Open. You can then make changes to the template in the Source Editor. bz\-%$^k
*/ xJ|_R,>.H
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package com.tot.count; dE]yb|Ld
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/** Ue2%w/Yo
* 6PdLJ#LS
* @author +/4wioGm
*/ 0mi$_Ld+
public class CountBean { x4%1P w
private String countType; ?Oyps7hXx
int countId; |h* rkLY
/** Creates a new instance of CountData */ l/g6Tv`w
public CountBean() {} (~OP)F).
public void setCountType(String countTypes){ c-q=Ct
this.countType=countTypes; o#=@!m
} WI}cXXUKm0
public void setCountId(int countIds){ )0N^rw kW
this.countId=countIds; >N8*O3
} 1XPYI
public String getCountType(){ 4"~l^yK
return countType; 1%`Nu ]D
} L wP
public int getCountId(){ qEajT"?
return countId; =]m,7 v Rq
} -cP7`.a
} E)z=85;_p
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CountCache.java .-4]FGg3
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/* @M&qH[tK-A
* CountCache.java i.Z iLDs\7
* Y4Y~ep
* Created on 2007年1月1日, 下午5:01 ,4H/>yPw
* 0AD8X+M{P
* To change this template, choose Tools | Options and locate the template under (Qf. S{;
* the Source Creation and Management node. Right-click the template and choose KGJ *h
* Open. You can then make changes to the template in the Source Editor. EaKbG>
*/ FL E3LH
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package com.tot.count; 14z
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import java.util.*; /X;/}fk
/** P"%f8C~r
* {@ Z=b5/P
* @author Yan}H}Oq
*/ kJK*wq]U6
public class CountCache { /I &wh
public static LinkedList list=new LinkedList(); @UQ421Z`
/** Creates a new instance of CountCache */ )=pa*
public CountCache() {} ],s{%a5wC
public static void add(CountBean cb){ t W}"PKv
if(cb!=null){ #\Zr$?t|V
list.add(cb); vEw8<<cgg
} 'Y0h w
} 6u>]-K5
} ?&?5x%|.<
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CountControl.java bs0[ a 1/
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/* Jq?Fi'2F%
* CountThread.java #Q'#/\5
* a:Nf+t
* Created on 2007年1月1日, 下午4:57 \,ne7G21j
* 3~1Gts
* To change this template, choose Tools | Options and locate the template under {mUt|m7!
* the Source Creation and Management node. Right-click the template and choose M+*K-zt0
* Open. You can then make changes to the template in the Source Editor. ![9$ru
*/ {2 k]$|
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package com.tot.count; r
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import tot.db.DBUtils; uS5G(} [
import java.sql.*; zx5#eMD
/** lffw
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* 8u%,5GV>Xr
* @author C_Z/7x*>d
*/ BA[ uO3\4
public class CountControl{ pu5%$}dBE
private static long lastExecuteTime=0;//上次更新时间 zf>*\pZE
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g(9kc<`3'D
/** Creates a new instance of CountThread */ i+F*vTM2,
public CountControl() {} F^Bk @
public synchronized void executeUpdate(){ %o5'M^U
Connection conn=null; J/IRCjQ}
PreparedStatement ps=null; e_"m\e#N
try{ 3"juj'
conn = DBUtils.getConnection(); 4/%Y@Z5
conn.setAutoCommit(false); `NTtw;%Y
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); N<ux4tz
for(int i=0;i<CountCache.list.size();i++){ H32o7]lT
CountBean cb=(CountBean)CountCache.list.getFirst(); N\];{pe>
CountCache.list.removeFirst(); w3z'ZCcr;"
ps.setInt(1, cb.getCountId()); \B^NdG5Y
ps.executeUpdate();⑴ Y'5(exW
//ps.addBatch();⑵ >bd@2au9!
} \KzH5 ?
//int [] counts = ps.executeBatch();⑶ 7377g'jL
conn.commit(); 8Ihl}aguW
}catch(Exception e){ ,`02fMOLc
e.printStackTrace(); 9ln=f=
} finally{ 8N+T=c
try{ PfyJJAQ[
if(ps!=null) { I)yF!E &
ps.clearParameters(); t0GJ$])
ps.close(); Rj4C-X4=
ps=null; 1=7ASS9
} 5\=
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}catch(SQLException e){} !l=)$RJKdD
DBUtils.closeConnection(conn); ]Vmo>
} )$1>6C\
} DIw_"$'At
public long getLast(){ zj(V\y&H
return lastExecuteTime; *c [^/
} \=7jp|{Yl
public void run(){ KPI96P
long now = System.currentTimeMillis(); 1]eRragm"
if ((now - lastExecuteTime) > executeSep) { ;g? |y(xv
//System.out.print("lastExecuteTime:"+lastExecuteTime); Mn/@?K?y
//System.out.print(" now:"+now+"\n"); hl7 z1h
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S1I.l">P
lastExecuteTime=now; yi*EobP
executeUpdate(); \hZ%NLj
} ]d-.Mw,'
else{ $xbW*w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (wM` LE(Ks
} pA8As
} ];4!0\M
} 5QLK
//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 P!E2.K,
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类写好了,下面是在JSP中如下调用。 BkGExz
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<% @qan &?-Y
CountBean cb=new CountBean(); J
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); uBa<5YDF
CountCache.add(cb); 3,Yr%`/5'
out.print(CountCache.list.size()+"<br>"); 1*Pxndt&
CountControl c=new CountControl(); nAEyL+6U
c.run(); %ACW"2#(
out.print(CountCache.list.size()+"<br>"); w|-3X
%>