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: 7#g<fh
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CountBean.java JNA_*3'
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/* <@v|~AO4~
* CountData.java b]WvKdq
* r+MqjdXG
* Created on 2007年1月1日, 下午4:44 :O*62olC5
* Tz/[P:O3
* To change this template, choose Tools | Options and locate the template under hnv0Loe.IW
* the Source Creation and Management node. Right-click the template and choose DH4|lb}
* Open. You can then make changes to the template in the Source Editor. FJB
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*/ ~HBx5Cpi
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package com.tot.count; B=i%Z_r]w
* \tR
/** N)YoWA>#bF
* :-b-)*TC;
* @author ^coj ETOv
*/ /5:qS\Zl
public class CountBean { @])}+4D(S
private String countType; 35SL*zS@-
int countId; &$pA,Gjin\
/** Creates a new instance of CountData */ .@Jos^rxgJ
public CountBean() {} Dr#V^"Dte
public void setCountType(String countTypes){ < 'r<MA<
this.countType=countTypes; j1dz'G}hj
} I#CS;Yh95
public void setCountId(int countIds){ N*Xl0m(Q
this.countId=countIds; A)f/ww)Q
} 9/5EyV
public String getCountType(){ tkhEjTZ
return countType; -k3WY&9,
} ]8XIw`:f
public int getCountId(){ #U/L8
return countId; aDX4}`u
} Qlhm:[
} Eqt>_n8
2!Pwg0%2
CountCache.java 2{)<Df@
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/* `b[@GGv
* CountCache.java :,MI,SwnS
* ~*G}+Ur$2
* Created on 2007年1月1日, 下午5:01 vg[zRWh8
* O u{|o0
* To change this template, choose Tools | Options and locate the template under j(Tk6S
* the Source Creation and Management node. Right-click the template and choose ?h ym~,
* Open. You can then make changes to the template in the Source Editor. +D#.u^
*/ 8X=2# &)
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package com.tot.count; 9h^TOZK)
import java.util.*; Qkg([q4
/** d/Fy0=0
* )$E'2|Gm/
* @author xh!aB6m8R
*/ L(kW]
public class CountCache { wRE2rsXoU
public static LinkedList list=new LinkedList(); ;UWp0d%
/** Creates a new instance of CountCache */ x/#.%Ga#T
public CountCache() {} !Ka~X!+\
public static void add(CountBean cb){ eLop}*k
if(cb!=null){ .+ CMm5T
list.add(cb); >tV:QP]Y
} 78u=J z6
} -<q@0IYyi
} =&;}#A%m
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CountControl.java is=|rY9$
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/* >4AwjS}H
* CountThread.java coc:$Sr%
* P,SI0$Z
* Created on 2007年1月1日, 下午4:57
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* hHqsI`7c
* To change this template, choose Tools | Options and locate the template under ~=pyA#VVJ"
* the Source Creation and Management node. Right-click the template and choose Bd*\|M
* Open. You can then make changes to the template in the Source Editor. Fk&A2C}$b
*/ L"V~MF
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package com.tot.count; DBzF\-
import tot.db.DBUtils; %{";RfSVX%
import java.sql.*; Y t0s
/** ;i;;{j@$i
* :<E\&6# oC
* @author ZUeA&&{
*/ y O?52YO
public class CountControl{ ~Uaz;<"j0
private static long lastExecuteTime=0;//上次更新时间 bR|1*<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <fcw:Ae
/** Creates a new instance of CountThread */ xT3l>9i
public CountControl() {} Dlu]4n[LB
public synchronized void executeUpdate(){ /pnQKy.
Connection conn=null; C)qP9uW
PreparedStatement ps=null; ,DWC=:@X
try{ fm^)u"
conn = DBUtils.getConnection(); 38(|a5
conn.setAutoCommit(false); JWs?az
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W|[k]A` 2
for(int i=0;i<CountCache.list.size();i++){ G X>T~i\f8
CountBean cb=(CountBean)CountCache.list.getFirst(); T1~,.(#
CountCache.list.removeFirst(); u=p-]?
ps.setInt(1, cb.getCountId()); kn7Qvk[+
ps.executeUpdate();⑴ e!*%U=[Q
//ps.addBatch();⑵ u:O6MO9^
} jj"?#`cW
//int [] counts = ps.executeBatch();⑶ U-:_4[
conn.commit(); ~m@w p
}catch(Exception e){
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e.printStackTrace(); .FAuM~_99b
} finally{ 6dX l ny1H
try{ h2Jdcr#@FF
if(ps!=null) { DYvg ^b
ps.clearParameters(); pNR69/wGi
ps.close(); 1`8(O >5
ps=null; oq }Q2[.b
} vH9Gf
}catch(SQLException e){} t>>\U X
DBUtils.closeConnection(conn); J*CfG;Y:
} /w*;|4~Bf
} ^5![tTJ
public long getLast(){ #o-CG PE
return lastExecuteTime; $5m_)]w4a
} jF%[.n[BU
public void run(){ LC:bHM,e
long now = System.currentTimeMillis(); M4TFWOC1
if ((now - lastExecuteTime) > executeSep) { W&(98}oT
//System.out.print("lastExecuteTime:"+lastExecuteTime); rSfvHO:R
//System.out.print(" now:"+now+"\n"); 1f`=U0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )Y+?)=~
lastExecuteTime=now; hV4B?##O
executeUpdate(); .Qeml4(`3
} )|zna{g\
else{ 0^{?kg2o_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :,(ZMx\
} d[.JEgU
} (KxL*gB
} 0Ku%9wh-
//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 HR83{B21
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类写好了,下面是在JSP中如下调用。 !56gJJ-r
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<% NQ(}rr'.
CountBean cb=new CountBean(); tcxs%yWO1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S4Vv _k-&
CountCache.add(cb); ku}I;k |
out.print(CountCache.list.size()+"<br>"); l6Q75i)eF
CountControl c=new CountControl(); #GHLF
c.run(); ]xIfgSq
out.print(CountCache.list.size()+"<br>"); [#R<Z+c
%>