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: } Yjic4?
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CountBean.java aR*z5p2-w
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/* kpxd+w
* CountData.java )h2wwq0]
* _9\ayR>d
* Created on 2007年1月1日, 下午4:44 QOy+T6en
* DH)@8)C
* To change this template, choose Tools | Options and locate the template under niqi DT/
* the Source Creation and Management node. Right-click the template and choose D-E30b]e
* Open. You can then make changes to the template in the Source Editor. _2 }i8q:
*/ &wK%p/?
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package com.tot.count; 1 /7H` O?
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/** @e$zEj5
* !;zacw
* @author 224I%x.,
*/ {j ${i
public class CountBean { t}_qtO7>
private String countType; `)1_^# k
int countId; Z fL\3Mn
/** Creates a new instance of CountData */ <CzH'!FJN
public CountBean() {} RfEmkb<9Z
public void setCountType(String countTypes){ =NH:/j^
this.countType=countTypes; >[O
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} z)]_ (zZ^
public void setCountId(int countIds){ 7=Ew[MOmM
this.countId=countIds; _Bb/~^
} h1FM)n[E7
public String getCountType(){ % ]r@vjeyd
return countType; xo7H^!_
} d_1w
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public int getCountId(){ )/Ee#)z*
return countId; ?9OiF-:n
} 0Evmq3,9
} {-7];e
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CountCache.java T%
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/* x AkM_<
* CountCache.java R`!x<J
* ^r}^-
* Created on 2007年1月1日, 下午5:01 ~ NKw}6
* 2\CFt;fk
* To change this template, choose Tools | Options and locate the template under Z[ZqQ` 7N
* the Source Creation and Management node. Right-click the template and choose 8e[kE>tS._
* Open. You can then make changes to the template in the Source Editor. `GqS.O}C
*/ 'fy1'^VPAV
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package com.tot.count; u6awcn
import java.util.*; |Y0BnyGK
/** kbM 4v G
* {%N*AxkvId
* @author |L%F`K>Z:
*/ K e~a
public class CountCache { t
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public static LinkedList list=new LinkedList(); _F;(#D
/** Creates a new instance of CountCache */ FC.y%P,
public CountCache() {} l`[*b_
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public static void add(CountBean cb){ B&O931E7
if(cb!=null){ m%qah>11
list.add(cb); ^z"90-V^
} ,l.O @
} ]+
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} 6AUXYbK,
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CountControl.java iVFHr<zk
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/* ,*bI0mFZ
* CountThread.java ^7.864
* Pi40w+/
* Created on 2007年1月1日, 下午4:57 [JO'ta
* {h7*a=
* To change this template, choose Tools | Options and locate the template under 600-e;p
* the Source Creation and Management node. Right-click the template and choose BN|+2D+S
* Open. You can then make changes to the template in the Source Editor. #T99p+O
*/ I}kx;!*b
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package com.tot.count; :@`Ll;G
import tot.db.DBUtils; z<m,Xj4w
import java.sql.*; f:KKOLm
/** =xS(Er`r
* n^UrHHOL
* @author 9V0iV5?( P
*/ >C*q
public class CountControl{ 1WfN_JKB5
private static long lastExecuteTime=0;//上次更新时间 Y6?d
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <fJoHS
/** Creates a new instance of CountThread */ 6HCP1`gg
public CountControl() {} q\x*@KQgM
public synchronized void executeUpdate(){ "qu%$L
Connection conn=null; 15)=>=1mR.
PreparedStatement ps=null; c_yf=
try{ :05>~bn>pC
conn = DBUtils.getConnection(); k10dkBoEX
conn.setAutoCommit(false); pV=X
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :eo2t>zF-<
for(int i=0;i<CountCache.list.size();i++){ Om\?<aul
CountBean cb=(CountBean)CountCache.list.getFirst(); 0N;Pb(%7UU
CountCache.list.removeFirst(); "e&S*8QhM
ps.setInt(1, cb.getCountId()); WW:@% cQ@
ps.executeUpdate();⑴ #]_S{sO
//ps.addBatch();⑵
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} /E2/3z
//int [] counts = ps.executeBatch();⑶ :y"Zc1_E
conn.commit(); j\P47q'v#
}catch(Exception e){ w3:Y]F.ot
e.printStackTrace(); JY"<b6C^
} finally{ #c5G"^)z
try{ NFDi2L>Ba
if(ps!=null) { Y`uL4)hR5
ps.clearParameters(); A%Pjg1(uX
ps.close(); &\F`M|c
ps=null; g|9'Lk
} ((SN We
}catch(SQLException e){} JY(_}AAu
DBUtils.closeConnection(conn); p,* rVz[Y
} J-:\^uP
} )Jz L
public long getLast(){ /(bPc12
return lastExecuteTime; a-MDZT<xA+
} ~]*P/'-{#
public void run(){ j="{^b
long now = System.currentTimeMillis(); Hq?-e?Nc
if ((now - lastExecuteTime) > executeSep) { :D-My28'
//System.out.print("lastExecuteTime:"+lastExecuteTime); 21O!CvX
//System.out.print(" now:"+now+"\n"); ? DWF7{1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;[R{oW
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lastExecuteTime=now; ;sE;l7
executeUpdate(); )(oRJu)y
} u}W R1u[
else{ 9KN75<n
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); AMp[f%X
} v/
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} :rnn`/L
} ryy".'v
//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 zF[kb%o
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类写好了,下面是在JSP中如下调用。 *)gbKXb
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<% xL3-(K6e
CountBean cb=new CountBean(); ycg5S rg
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ow,I|A
CountCache.add(cb); ;f:}gMK
out.print(CountCache.list.size()+"<br>"); *,.WI )@
CountControl c=new CountControl(); lEL&tZ}
c.run(); 2>80Qp!xO
out.print(CountCache.list.size()+"<br>"); @" UoQ_h%
%>