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: ]yIy~V
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CountBean.java _:K}DU'6
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/* Bhs`Y/Ls-
* CountData.java dY|jV}%T
* hqds T
* Created on 2007年1月1日, 下午4:44 eoL)gIM%
* ttKfZ0
* To change this template, choose Tools | Options and locate the template under b,`\"'1
* the Source Creation and Management node. Right-click the template and choose s24H.>Z
* Open. You can then make changes to the template in the Source Editor. C {,d4KG
*/ (i?^g &
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package com.tot.count; [ho'Pc3A<
*7v PU:Q[
/** 6,h<0j{
* jF5JpyOc
* @author 0jzA\ $oD
*/ 5 O6MI4:
public class CountBean { FD-)nv2:
private String countType; <5#e.w
int countId; :_H88/?RR
/** Creates a new instance of CountData */ *&PgDAQ
public CountBean() {} n^%u9H
public void setCountType(String countTypes){ vJ'ho
this.countType=countTypes; s6]f#s5o
} bc"N
public void setCountId(int countIds){ POG5x
this.countId=countIds; +OH."4Z
} V&nN/CF
public String getCountType(){ .=FJ5?:4i%
return countType; #Nd+X@j
} 2X]\:<[4
public int getCountId(){ B>mQ\Q
return countId; <>:kAT,sP
} M@K[i*e
} 5a~1RL
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CountCache.java onlyvH4
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/* yh)q96m-V=
* CountCache.java o&O!Ur
* **"P A8
* Created on 2007年1月1日, 下午5:01 @hvq,[
* w&gHmi
* To change this template, choose Tools | Options and locate the template under hJ@nW5CI
* the Source Creation and Management node. Right-click the template and choose ^v'Lu!\f
* Open. You can then make changes to the template in the Source Editor. {8MF!CG]
*/ y*D 8XI$
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package com.tot.count; b1OB'P8
import java.util.*; 5 9vGLN!L
/** ;@
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* cjW]Nw
* @author %Fv)$ :b
*/ #? *jdN:
public class CountCache { d0^2<
public static LinkedList list=new LinkedList(); +x2xQ8#|~~
/** Creates a new instance of CountCache */ GND[f}
public CountCache() {} O+N-x8W{
public static void add(CountBean cb){ <gy'@w?
if(cb!=null){ 6>Cubb>
list.add(cb); tFQFpbI
} $3ILVT
} KOQTvJ_#
} Bz{
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CountControl.java 5-*]PAC
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/* k
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* CountThread.java c>Se Onf
* ;GAYcVB
* Created on 2007年1月1日, 下午4:57 2$91+N*w9
* 1rEP)66N
* To change this template, choose Tools | Options and locate the template under Xwi&uyvU&
* the Source Creation and Management node. Right-click the template and choose TG9)x|!
* Open. You can then make changes to the template in the Source Editor. p1nA7;B-m
*/ bqO"k t
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package com.tot.count; !iw
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import tot.db.DBUtils; ^~ Sn{esA
import java.sql.*; f+V':qz
/** EHZSM5hu
* "Tv7*3>
* @author ~-+Zu<
*/ 'gGB-=yvbO
public class CountControl{ *`#,^p`j
b
private static long lastExecuteTime=0;//上次更新时间 TRZ^$<AG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 vF&b|V+,
/** Creates a new instance of CountThread */ Nz;;X\GI
public CountControl() {} YSgF'qq\
public synchronized void executeUpdate(){ )VT/kIq-U
Connection conn=null; {/<&
PreparedStatement ps=null; +mQSlEo
try{ pQNFH)=nw
conn = DBUtils.getConnection(); o__q)"^~-
conn.setAutoCommit(false); L
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 6{'6_4;Fv(
for(int i=0;i<CountCache.list.size();i++){ 2XHk}M|
CountBean cb=(CountBean)CountCache.list.getFirst(); meR2"JN'
CountCache.list.removeFirst(); MlFvDy
ps.setInt(1, cb.getCountId()); jGn^<T\
ps.executeUpdate();⑴ n lW&(cH
//ps.addBatch();⑵ 0, /x#
} &iZYBa
//int [] counts = ps.executeBatch();⑶ e`r;`a&
conn.commit(); {P&^Erx
}catch(Exception e){ o2
e.printStackTrace(); 8:xo ~Vc
} finally{ Bv8C_-lV/
try{ VaxO L61xE
if(ps!=null) { __j8jEV
ps.clearParameters(); nY)Pxahm 7
ps.close(); lG9ARRy(=
ps=null; )*ckJK
} Q8?D}h
}catch(SQLException e){} EcIQ20Z_-
DBUtils.closeConnection(conn); \]xYV}(FO
} `Ny8u")=
} 1 1CJT
public long getLast(){ s? k[_|)!
return lastExecuteTime; "44?n <1
} jm\#($gl=
public void run(){
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long now = System.currentTimeMillis(); "ux]kfoT
if ((now - lastExecuteTime) > executeSep) { AvZ) 1(
//System.out.print("lastExecuteTime:"+lastExecuteTime); {R;M`EU>
//System.out.print(" now:"+now+"\n"); yU,xcq~l
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &F_rg,q&_
lastExecuteTime=now; tY=%@v'6?
executeUpdate(); Kdu\`c-lB
} 8F`
else{ )1Nnn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vLv@ Mo
} Cg pT(E\E
} )H)Udhz
} 1 ],,
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 1m;*fs
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类写好了,下面是在JSP中如下调用。 #Hi]&)p_
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<% 1Uk~m
CountBean cb=new CountBean(); 2F@)nh
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ch"8cl;Fm
CountCache.add(cb); g ypq`F
out.print(CountCache.list.size()+"<br>"); Y>Hl0$:=
CountControl c=new CountControl(); _`i%9Ad.4
c.run(); K#hY bDm
out.print(CountCache.list.size()+"<br>"); d`uO7jlm
%>