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: H
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CountBean.java w1je|Oil
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/* 2^}E!(<
* CountData.java =vv4;az
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* xt%-<%s %f
* Created on 2007年1月1日, 下午4:44 4EO,9#0
* U2DE"
* To change this template, choose Tools | Options and locate the template under YmS}*>oz
* the Source Creation and Management node. Right-click the template and choose f,?P1D\
* Open. You can then make changes to the template in the Source Editor. ]&')#YO
*/ c:/H}2/C
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package com.tot.count; =c-,uW11[
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/** <3wfY
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* i U^tv_1
* @author <4gT8kQ$x
*/ [ET03 nZ
public class CountBean { ;BsPms@U
private String countType; >&|C
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int countId; _7AR2
/** Creates a new instance of CountData */ MVGznf?
public CountBean() {} 5/:BtlFx
public void setCountType(String countTypes){ rI\G&OqpP
this.countType=countTypes; 6d RxfbL
} 6w
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public void setCountId(int countIds){ h|_E>6d)
this.countId=countIds; Sc!{
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} qjsS2,wM
public String getCountType(){ ;'.[h*u~<
return countType; 0u]!C"VX
} Xgge_`T9
public int getCountId(){ 6iiH+Nc
return countId; -/>SdR$D7
} =kp-[7
} O<0G\sU
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CountCache.java Z\{"/( Hi
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/* `wJR^O!e
* CountCache.java H5f>Q0jq
* +Mb;;hb
* Created on 2007年1月1日, 下午5:01 uY,(3x
* -I$qe Xy
* To change this template, choose Tools | Options and locate the template under 6gLk?^.
* the Source Creation and Management node. Right-click the template and choose $nB4Ie!WcR
* Open. You can then make changes to the template in the Source Editor. y{.s
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*/ 4,o|6H
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package com.tot.count; mCa[?
import java.util.*; YxEc(a"
/** +mReWf:o
* 3x=f}SO&
* @author <+1d'VQ2
*/ 3|=9aM^ x^
public class CountCache { #S57SD
public static LinkedList list=new LinkedList(); =Fq"lq %
/** Creates a new instance of CountCache */ ,\y)k}0lH
public CountCache() {} x
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public static void add(CountBean cb){ ]-Z="YPY
if(cb!=null){ _;]
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list.add(cb); ; ]*
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} H\OV7=8
} [
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} gK {-eS
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CountControl.java L'dR;T[;
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/* !ejLqb
* CountThread.java > .L\ >
* 1 m)WM,L
* Created on 2007年1月1日, 下午4:57 JG%y_
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* ^-,
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* To change this template, choose Tools | Options and locate the template under UN7>c0B
* the Source Creation and Management node. Right-click the template and choose g1JBssw&m
* Open. You can then make changes to the template in the Source Editor. }B=`nbgIG7
*/ Y)kO"
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package com.tot.count; .w/_Om4T*b
import tot.db.DBUtils; K:!|xr(1d
import java.sql.*; ]]
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/** ?0>%
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* (Kl96G<Wej
* @author <r_L-
*/ F;5S2:a@Z
public class CountControl{ Nr\[|||%
private static long lastExecuteTime=0;//上次更新时间 zJnF#G
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0v%ZKvSID
/** Creates a new instance of CountThread */ EgAM,\
public CountControl() {} W0n/B&C
public synchronized void executeUpdate(){ n\f8%z
Connection conn=null; }<y-`WB
PreparedStatement ps=null; xXpeo_y'
try{ yQA6w%
conn = DBUtils.getConnection(); |/u&%w?W
conn.setAutoCommit(false); Ww9%6 #it
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); &,pL3Qos
for(int i=0;i<CountCache.list.size();i++){ =2[5g!qX
CountBean cb=(CountBean)CountCache.list.getFirst(); '.jr" 3u
CountCache.list.removeFirst(); C
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ps.setInt(1, cb.getCountId()); 7^}np^[HB
ps.executeUpdate();⑴ Y`5(F>/RQG
//ps.addBatch();⑵ | |=q"h3(
} &tT*GjPwg;
//int [] counts = ps.executeBatch();⑶ ?lg
conn.commit(); j]uL9\>
}catch(Exception e){ r+T@WvS%W
e.printStackTrace(); T%
} finally{ ys+ AY^/
try{ K:PPZ|
if(ps!=null) { E1(2wJ-3"
ps.clearParameters(); KkVFY+/)
ps.close(); ZJCD)?]=3
ps=null; ZP>KHiA
} a}~Xns
}catch(SQLException e){} >syQDB
DBUtils.closeConnection(conn); HmWU;9Vn+
} 86bl'FdKS
} s8,N9o[.~P
public long getLast(){ L*TPLS[lh
return lastExecuteTime; xz1jRI$
} u{F^Ngy
)
public void run(){ zKycd*X
long now = System.currentTimeMillis(); ykY#Y}?^
if ((now - lastExecuteTime) > executeSep) { 0'Kbh$LU
//System.out.print("lastExecuteTime:"+lastExecuteTime); r;gtfX*
//System.out.print(" now:"+now+"\n"); pBW|d\8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <ob+Ano$
lastExecuteTime=now; t{\,vI
executeUpdate(); {ZiZ$itf
} 9C?;'
else{ )<w`E{q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6\MH2&L<
} g<,kV(_7
} [yzDa:%
} T~shJ0%
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 JZQT}
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类写好了,下面是在JSP中如下调用。 ]JQ';%dne
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<% H5@N<v5u
CountBean cb=new CountBean(); RQzcsO
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); rQ0V3x1"Qx
CountCache.add(cb); F$l]#G.@A
out.print(CountCache.list.size()+"<br>"); Ep/kb-~-
CountControl c=new CountControl(); [nQ<pTg~r
c.run(); N1dp%b9W(
out.print(CountCache.list.size()+"<br>"); 9cJzL"yi
%>