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+e!>"
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CountBean.java 0Zt=1Tv
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/* j k%MP6
* CountData.java $VWeo#b
* C q/936`O
* Created on 2007年1月1日, 下午4:44 Im
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* &"D *
* To change this template, choose Tools | Options and locate the template under {uurM`f}:
* the Source Creation and Management node. Right-click the template and choose Jj<UtD+
* Open. You can then make changes to the template in the Source Editor. TRQ@=.
*/ :8}iZ.
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package com.tot.count; ]et4B+=i
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/** *z2G(Uac
* fl{wF@C6
* @author a?LrSk`
*/ 6g/ <FM
public class CountBean { &WSxg&YG)\
private String countType; \q2#ef@2
int countId; o80"ZU|=
/** Creates a new instance of CountData */ 6m#V=4e*
public CountBean() {} 7j9:s>D
public void setCountType(String countTypes){ [dm&I#m=
this.countType=countTypes; a[<'%S#3x
} C2WWS(zn
public void setCountId(int countIds){ m5O;aj* i
this.countId=countIds; t>D|1E"
} ,o$F~KPu
public String getCountType(){ AlW0GK=N-p
return countType; @ ;%+Ms
} o:H^
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public int getCountId(){ vwVK^B
return countId; #) eI]
} nz72w_
} 2V6=F[T
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CountCache.java gyqM&5b
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/* fE1B1j<
* CountCache.java `6`p ~
* CqMm'6;$a}
* Created on 2007年1月1日, 下午5:01 )tH.P:
1~,
* ?LJDBN
* To change this template, choose Tools | Options and locate the template under n#jBqr&!M
* the Source Creation and Management node. Right-click the template and choose $XBn:0U
* Open. You can then make changes to the template in the Source Editor. Lk?%B)z
*/ Gm,vLs9H$T
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package com.tot.count; G?:{9. (
import java.util.*; gN2$;hb?
/** zf@gA vJ
* l;*/F`>c
* @author -6 WjYJx
*/ HGuU6@~hu
public class CountCache { <evvNSE
public static LinkedList list=new LinkedList(); kEQ1&9
/** Creates a new instance of CountCache */ "r!>p\.0O
public CountCache() {} 4@2<dw|*h
public static void add(CountBean cb){ p~Tp=d)/
if(cb!=null){
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list.add(cb); [i[*xf-B
} r[doN{%
} yyp0GV.x
} K|i:tHF]@
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CountControl.java &cZQ,o
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/* ew13qpt)<L
* CountThread.java g=Gd|
*
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* Created on 2007年1月1日, 下午4:57 :;Lt~:0b~
* o,-p[1b
* To change this template, choose Tools | Options and locate the template under jeKqS
* the Source Creation and Management node. Right-click the template and choose /
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* Open. You can then make changes to the template in the Source Editor. ;(&$Iw9X
*/ Lud[.>i
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package com.tot.count; 4*AkUkP:T
import tot.db.DBUtils; ,/fB~On-
import java.sql.*; *B4?(&0
/** .<m${yU{3
* CP]nk0
* @author {GH0>
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*/ 6TR` O
public class CountControl{ (vR9vOpJ
private static long lastExecuteTime=0;//上次更新时间 Yvi.l6JL
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 tPp9=e2[s
/** Creates a new instance of CountThread */ g~7x+cu0
public CountControl() {} W
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public synchronized void executeUpdate(){ 5dvP~sw
Connection conn=null; c-`'`L^J
PreparedStatement ps=null; !_?K(X~/
try{ YW14X
conn = DBUtils.getConnection(); ,`pUz[wl
conn.setAutoCommit(false); 0?$jC-@k:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <r>1W~bp.q
for(int i=0;i<CountCache.list.size();i++){ ]>9[}'u
CountBean cb=(CountBean)CountCache.list.getFirst(); 5cUz^ >
CountCache.list.removeFirst(); /f*QxNZ,p
ps.setInt(1, cb.getCountId()); nF5\iV
ps.executeUpdate();⑴ gAudL)X
//ps.addBatch();⑵ 3wYhDxY1
} 67tB8X
//int [] counts = ps.executeBatch();⑶ ]/#3 P
conn.commit(); nk*T
x
}catch(Exception e){ 9#>t% IF~
e.printStackTrace(); !MyCxM6
} finally{ `
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try{ S4Q
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if(ps!=null) { ?3_^SRW&a
ps.clearParameters(); I.6
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ps.close(); d)WGI
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ps=null; 1CR)1H
} C JYpgSr
}catch(SQLException e){}
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DBUtils.closeConnection(conn); ?mp}_x#=
} Im!fZ g
} 7~qyz]KkE
public long getLast(){ ^Q#g-"b
return lastExecuteTime; uPVO!`N3
} &SW~4 {n:
public void run(){ ]<BT+6L
long now = System.currentTimeMillis(); &5y|Q?
if ((now - lastExecuteTime) > executeSep) { c }7gHud
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3Viz0I<%
//System.out.print(" now:"+now+"\n"); {00Qg{;K|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~f6Q
lastExecuteTime=now; P,s>xM
executeUpdate(); Rn $TYCO
} 7PbwCRg
else{ sh/4ui{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Y`*h#{|
} u#+Is4Vh
} S[e> 8
} -PCFOm"
//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 no,b_0@N
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类写好了,下面是在JSP中如下调用。 $EnBigb!
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<% G.:QA}FE'
CountBean cb=new CountBean(); `PtfPt<{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); HE:]zH
CountCache.add(cb); MmQk@~
out.print(CountCache.list.size()+"<br>"); ,R}9n@JI^Y
CountControl c=new CountControl(); g!;a5p6
c.run(); f_z]kA
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out.print(CountCache.list.size()+"<br>"); J%IKdxa
%>