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: eI=Y~jy
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CountBean.java ZTPOD.:#
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/* >s 8:1l
* CountData.java Dxa)7dA|
* T.m)c%]^/
* Created on 2007年1月1日, 下午4:44 A2O_pbQti
* "TH-A6v1
* To change this template, choose Tools | Options and locate the template under O"s`-OM;n
* the Source Creation and Management node. Right-click the template and choose '__3[D
* Open. You can then make changes to the template in the Source Editor. ZNH*[[Pf
*/ GT\s!D;<
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package com.tot.count; eS@!\Hx
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/** 7s fuju(
* 9bcyPN
* @author cmGj0YUQ1
*/ ga1gd~a
public class CountBean { %_@5_S
private String countType; DneSzqO"o
int countId; SeJFZ0p
/** Creates a new instance of CountData */ k4AE`[UE
public CountBean() {} I }W-5%
public void setCountType(String countTypes){ KutgW#+40
this.countType=countTypes; ':R3._tw\
} +8vzkfr3It
public void setCountId(int countIds){ 7Ae,|k
this.countId=countIds; g$-D?~(Z
} 3f2Hjk7,d
public String getCountType(){
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return countType; ;R|#ae@
} ~:b:_ 5"
public int getCountId(){ $8T|r+<
return countId; r dG2| Tp
} 1q233QSW)
} =&*QT&e
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CountCache.java QB|fFj58u
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/* VU0tyj$
* CountCache.java .]ZuG
* lbuW*)
* Created on 2007年1月1日, 下午5:01 =UKR<@QrK
* .gkPG'm[
* To change this template, choose Tools | Options and locate the template under .8PO7#
* the Source Creation and Management node. Right-click the template and choose %d#)({N
* Open. You can then make changes to the template in the Source Editor. qfH~h g
*/ >0+|0ba
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package com.tot.count; cxJK>%84
import java.util.*; I/b8
/** ?kFCYZK|"
* +=H>s;B
* @author ,JBw$C
*/ Am?Hkh2
public class CountCache { 8OtUY}R
public static LinkedList list=new LinkedList(); WT!\X["FI$
/** Creates a new instance of CountCache */ a*8.^SdzR
public CountCache() {} ;@Hi*d[
public static void add(CountBean cb){ rn5g+%jX*
if(cb!=null){
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list.add(cb); ]GRq
} DUliU8B}\
} @SG="L
} 8\.1m9&r>o
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CountControl.java irw 7
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/* )~mc1U`b
* CountThread.java aC
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* m#K%dR
* Created on 2007年1月1日, 下午4:57 eF;1l<<
* b`|MK4M(
* To change this template, choose Tools | Options and locate the template under `FB?cPR
* the Source Creation and Management node. Right-click the template and choose C<@1H>S4_
* Open. You can then make changes to the template in the Source Editor. Qp.!U~
*/ #!&R7/
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package com.tot.count; jv=f@:[`I
import tot.db.DBUtils; KeHE\Fq^V
import java.sql.*; KB *#t
/** g2>u]3&W
* wJR i;fvi
* @author _
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*/ qe"6#@b *|
public class CountControl{ ;AB ,:*
private static long lastExecuteTime=0;//上次更新时间 O*/-I
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 GJt9hDM$0
/** Creates a new instance of CountThread */ 5a|m}2IX
public CountControl() {} 8lGgp&ey
public synchronized void executeUpdate(){ (Dh;=xG
Connection conn=null; k8wi-z[dV
PreparedStatement ps=null; W
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try{ Ci9wF(<k
conn = DBUtils.getConnection(); V;]VwsZ"
conn.setAutoCommit(false); 14YV#o:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `b`52b\6S
for(int i=0;i<CountCache.list.size();i++){ c%/&@vs7
CountBean cb=(CountBean)CountCache.list.getFirst(); UVmyOC[Y{
CountCache.list.removeFirst(); & O\!!1%
ps.setInt(1, cb.getCountId()); 0@x$Cp
ps.executeUpdate();⑴ [K@!JY
//ps.addBatch();⑵ ~)IJE+e>}
}
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//int [] counts = ps.executeBatch();⑶ "v(]"L
conn.commit(); >8;%F<o2
}catch(Exception e){ d4h(F,K7V
e.printStackTrace(); )[X!/KR90
} finally{ )bU")
try{ )0d".Q|v4
if(ps!=null) { bK;aV&
ps.clearParameters(); (ai-n,y
ps.close(); |A/_Qe|s2
ps=null; PjZvLK@a9)
} J*&=J6
}catch(SQLException e){} /~huTKA}
DBUtils.closeConnection(conn); LF.~rmPa
} QR$sIu@%
} :p)9Heu
public long getLast(){ n]c,0N
return lastExecuteTime; Wc;D{p?Lb
} JU1; /3(
public void run(){ #&c;RPac!6
long now = System.currentTimeMillis(); HFWm}vA:
if ((now - lastExecuteTime) > executeSep) { Ns8NaD
//System.out.print("lastExecuteTime:"+lastExecuteTime); WzbN=&
C]h
//System.out.print(" now:"+now+"\n"); VD`2lGdF
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9+Bq00-Z$
lastExecuteTime=now; Prx s2 i 8
executeUpdate(); kR?n%`&k
} C\@YH]
else{ sZBO_](S
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g}r5ohqC#
} 3^yWpSC
} Mf13@XEo
} K2`WcEe
//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 PH!B /D5G
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类写好了,下面是在JSP中如下调用。 @Hdg-f>y]
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<% VZbIU[5
CountBean cb=new CountBean(); ?Cfp=85ea!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^F9zS`Yz2
CountCache.add(cb); R*eM 1
out.print(CountCache.list.size()+"<br>"); 2#}IGZ`Yp/
CountControl c=new CountControl(); zn$Ld,
c.run(); Jiylrf`o
out.print(CountCache.list.size()+"<br>"); 1Klu]J%
%>