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: [G_ ;78
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CountBean.java *d8
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/* L1kn="5
* CountData.java ie1~QQ
* WI1YP0V
* Created on 2007年1月1日, 下午4:44 WL+EpNKSf
* ;6V~yB
* To change this template, choose Tools | Options and locate the template under C6>_wl]
* the Source Creation and Management node. Right-click the template and choose G? SPz
* Open. You can then make changes to the template in the Source Editor. _{o 3 y"DZ
*/ !!.@F;]W
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package com.tot.count; c44s@E
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/** Ku'a,\7z
* (cVIjo+::
* @author }0&Fu?sP
*/
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public class CountBean { ub?dfS9$_
private String countType; pW[TufTa
int countId; q>%B @'
/** Creates a new instance of CountData */ R*6TS"aL
public CountBean() {} YMo8C(
public void setCountType(String countTypes){ E?]$Y[KJKs
this.countType=countTypes; gYt=_+-
} V dJ
public void setCountId(int countIds){ ^qL<=UC.
this.countId=countIds; gPn0-)<
} +=W(c8~P
public String getCountType(){ Eq_@xT0>
return countType; /%g@ ;
} ",~ZO<P
public int getCountId(){ $bhI2%_`M
return countId; z^wod
} oyiG04H&
} n{W(8K6d@[
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CountCache.java =o~mZ/ 7=M
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/*
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* CountCache.java Wt%Wpb8
* /\,3AInLb
* Created on 2007年1月1日, 下午5:01 I?1BGaAA
* blomB2vQ
* To change this template, choose Tools | Options and locate the template under o5]-Kuw`
* the Source Creation and Management node. Right-click the template and choose ea{zL
* Open. You can then make changes to the template in the Source Editor. %S%UMA.
*/ {JdXn
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package com.tot.count; iklZ[G%A0
import java.util.*; l>|scs;TI
/** ~;b}_?%o
* wKJ|;o4;L
* @author _ow7E\70
*/ \E c*Gq?.
public class CountCache { [$} \Gv
public static LinkedList list=new LinkedList(); _gH$
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/** Creates a new instance of CountCache */ Ho#nM_ q
public CountCache() {} bRggt6$z
public static void add(CountBean cb){ `\##M=
if(cb!=null){ `)$G}7cRUH
list.add(cb); P*[wB_^&UP
} E;H9]*x/
} y.(<
} jcC"vr'u|
) M8,Tv*~
CountControl.java %4R1rUrgt|
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/* `#ff`j|a
* CountThread.java jBEW("4R
* o]I8Ghk>/z
* Created on 2007年1月1日, 下午4:57 Z6b]EcP)#
*
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* To change this template, choose Tools | Options and locate the template under }x#e.}hf&
* the Source Creation and Management node. Right-click the template and choose JS03BItt
* Open. You can then make changes to the template in the Source Editor. XlX t,
*/ J>M 9t%f@
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package com.tot.count; l_;6xkv4
import tot.db.DBUtils; %INkuNa8\
import java.sql.*; hKg +A
/** ;I@\}!%H
* /)RH-_63
* @author |oOAy
*/ 3
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public class CountControl{ P(-
private static long lastExecuteTime=0;//上次更新时间 u)zv`m
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7m%12=Im5
/** Creates a new instance of CountThread */ VL5VYv=:
public CountControl() {} k&L/JzzI
public synchronized void executeUpdate(){ 4C?4M;
Connection conn=null; )Ft+eMYti[
PreparedStatement ps=null; b{&'r~
try{ Wm{ebx
conn = DBUtils.getConnection(); \FX"A#
conn.setAutoCommit(false); n2_;:=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #%%!r$UL
for(int i=0;i<CountCache.list.size();i++){ ePq (.o
CountBean cb=(CountBean)CountCache.list.getFirst(); 2&pE
CountCache.list.removeFirst(); }l} _'FmQ
ps.setInt(1, cb.getCountId()); TC2%n\GH*
ps.executeUpdate();⑴ y5KeUMcu
//ps.addBatch();⑵ LRaO}-<b
} {2Ew^Li
//int [] counts = ps.executeBatch();⑶ <5Ll<0
conn.commit(); s1sn,?
}catch(Exception e){ `gCJ[
e.printStackTrace(); `t9k!y!GV
} finally{ g[O
try{ a*}>yad
if(ps!=null) { 4o";p}[b
ps.clearParameters(); y8C8~ -&OK
ps.close(); 'C`Ykjf
ps=null; *:+ZEFMq
} IMM+g]#e
}catch(SQLException e){} G$KQgUN~[
DBUtils.closeConnection(conn); j( k%w
} 0 ;)Q
} - q(a~Ge
public long getLast(){ k;JDVRL
return lastExecuteTime; m6^#pqSL
} ShlTMTgS
public void run(){ m<k6oev$
long now = System.currentTimeMillis(); )FG/
if ((now - lastExecuteTime) > executeSep) { b>i5r$S8G
//System.out.print("lastExecuteTime:"+lastExecuteTime); *ZLisq-f
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); T~L V\}h
lastExecuteTime=now; gMZ+kP`
executeUpdate(); _NwHT`O[
} LXJ;8uW2y
else{ 9@IL5 47V
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); NX8hFwR
} WI*CuJU<zJ
} QBi]gT@&g
} Q}l~n)=
//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 lup2>"?*
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类写好了,下面是在JSP中如下调用。 IsJx5GO
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<% oclU)f.,
CountBean cb=new CountBean(); SO STtuT
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ")txFe
CountCache.add(cb); 9LBZMQ
out.print(CountCache.list.size()+"<br>"); An`*![
CountControl c=new CountControl(); x@/:{B
c.run(); F#)bGi
out.print(CountCache.list.size()+"<br>"); j_h:_D4
%>