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: Yz+ZY
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CountBean.java 1^}[&ar
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/* Rx=>6,)'
* CountData.java ]z/8KL
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* Created on 2007年1月1日, 下午4:44 \6 Zr
* [rV>57`YD
* To change this template, choose Tools | Options and locate the template under 4p,EBn9(
* the Source Creation and Management node. Right-click the template and choose '|8} z4/g
* Open. You can then make changes to the template in the Source Editor. GE%Z9#E
*/ P 'od`
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package com.tot.count; DrY:9[LP
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/**
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* ?WqT[MnK
* @author /n{omx
*/ A#J`;5!Sc
public class CountBean { lHPd"3HDK
private String countType; f\sQO&
int countId; ]\hSI){
/** Creates a new instance of CountData */ NRIG 1v>
public CountBean() {} UMm!B `M
public void setCountType(String countTypes){ )9"_J9G
this.countType=countTypes; r\-uJ~8N
} b((M)Gz
public void setCountId(int countIds){ {CGUL|y
this.countId=countIds; _C*fs<#
} @] DVD
public String getCountType(){ }o?AP vd
return countType; S79;^X
} eoG$.M"
public int getCountId(){ |Sy<@oq
return countId; )I^7)x
} SBfT20z[
} yDegcAn?
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CountCache.java AicBSqUke
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/* (mTE;s(
* CountCache.java ~O
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* Created on 2007年1月1日, 下午5:01 Vr`R>S,-
* NflD/q/ L
* To change this template, choose Tools | Options and locate the template under \F/hMXDlJ
* the Source Creation and Management node. Right-click the template and choose x7!L{(E3
* Open. You can then make changes to the template in the Source Editor. %\dz
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*/ <66X Xh.
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package com.tot.count; 0zlb0[
import java.util.*; |@
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/** C.Kh[V\Ut
* i]YV {
* @author %,}A@H,
*/ 8QLj["
public class CountCache { pz\
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public static LinkedList list=new LinkedList(); IoQEtA
/** Creates a new instance of CountCache */ z<U-#k7nz
public CountCache() {} ORHp$Un~)
public static void add(CountBean cb){ ?mFv0_!O
if(cb!=null){ "4+&-ms
list.add(cb); "/3'XOK|
} @s ?
} l1OE!W W
} P2BWuhF
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CountControl.java }@'$b<!B
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/* .f%fHj
* CountThread.java K1"*.\?F
* V3Q+s8OIF
* Created on 2007年1月1日, 下午4:57 bMg(B-uF7
* Ui_8)z _
* To change this template, choose Tools | Options and locate the template under |ef7bKU8
* the Source Creation and Management node. Right-click the template and choose eTI%^d|
* Open. You can then make changes to the template in the Source Editor. [!HEQ8 2g
*/ "GMBjT8
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package com.tot.count; f33 2J
import tot.db.DBUtils; SPX$U5&
import java.sql.*; |:q=T
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/** v7BA[j Qr
* D[aCsaR
* @author }Z@ovsG
*/ 9ifDcYl
public class CountControl{ ~dgDO:)
private static long lastExecuteTime=0;//上次更新时间 ?I_s0k I
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %GjM(;Tk
/** Creates a new instance of CountThread */ p{amC ;cI$
public CountControl() {} );
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public synchronized void executeUpdate(){ z&#SPH*
Connection conn=null; 8uc1iB
PreparedStatement ps=null; +Mo9kC
try{ ov`h
conn = DBUtils.getConnection(); p
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conn.setAutoCommit(false); &=Ar
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Z&Pg"a?\
for(int i=0;i<CountCache.list.size();i++){ bH7X'%r
CountBean cb=(CountBean)CountCache.list.getFirst(); jVv0ST*z
CountCache.list.removeFirst(); ieDk ;
ps.setInt(1, cb.getCountId()); \r;#g{
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ps.executeUpdate();⑴ |oH,
//ps.addBatch();⑵ #%a;"w
} jaTh^L
//int [] counts = ps.executeBatch();⑶ 3oGt3F{gZ
conn.commit(); 'y;EhOwj,
}catch(Exception e){ sT 3^hY7
e.printStackTrace(); dpAjR
} finally{ Su
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try{ 8n#HFJ~
if(ps!=null) { PWaw]*dFmy
ps.clearParameters(); A -H&
ps.close(); FcR=v0),
ps=null; B:b5UD
} 1-%fo~!l
}catch(SQLException e){} 8p^bD}lN7
DBUtils.closeConnection(conn); cv-PRH#
}
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} / ;$#d}R
public long getLast(){ {C 6=[
return lastExecuteTime; iEVb"w059
} +X#vVD3"
public void run(){ aE`c%T):`
long now = System.currentTimeMillis(); _X^1IaL
if ((now - lastExecuteTime) > executeSep) { Q3n,)M[N
//System.out.print("lastExecuteTime:"+lastExecuteTime); q-[@$9AS
//System.out.print(" now:"+now+"\n"); .Xfq^'I[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); f/
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lastExecuteTime=now; 9_q#W'/X
executeUpdate(); (Mo*^pVr
} 5gb|w\N>
else{ )IP,;<
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0[RL>;D:
} Ed0QQyC@9
} _(_a*ml
} j@W.&- _
//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 '-r).Xk
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类写好了,下面是在JSP中如下调用。 N|8P)
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<% dbwe?ksh
CountBean cb=new CountBean(); :8L8q<U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <6EeD5{*
CountCache.add(cb); :By?O"LQ
out.print(CountCache.list.size()+"<br>"); o1-m1 <ft
CountControl c=new CountControl(); j-4VB_N@
c.run(); AYt%`Y.!
out.print(CountCache.list.size()+"<br>"); 3C?f(J}
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