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: s9bP6N!,
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CountBean.java R_&z2I
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/* }0>/G?2Yp
* CountData.java rO%+)M$A
* G_mu7w
* Created on 2007年1月1日, 下午4:44 }PL
* k ,(:[3J
* To change this template, choose Tools | Options and locate the template under i~L7h=__
* the Source Creation and Management node. Right-click the template and choose 'Jr*oru
* Open. You can then make changes to the template in the Source Editor. HbDB?s<
*/ ,!4_Uc
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package com.tot.count; qW >J-,61/
#[yl;1)
/** obolDha
* E_rC"_Zte
* @author tb\pjLB][
*/ 8!>pFVNJf
public class CountBean { AR3=G>hO,
private String countType; L"/ato
int countId; e,UgTxZ
/** Creates a new instance of CountData */ ^D[;JV
public CountBean() {} k>hZ
public void setCountType(String countTypes){ iUB ni&B
this.countType=countTypes; U .(_n
} BIyG[y?qO
public void setCountId(int countIds){ o2jB~}VMl
this.countId=countIds; '=* 5C{
} =oDrN7`,B
public String getCountType(){
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return countType; 4]KceE
} .&.CbE8K[
public int getCountId(){ >E=a~ O
return countId; qJj5J;k
} 9V\`{(R
} 0O4mA&&!oK
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CountCache.java o]U==
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/* z\
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* CountCache.java Y%@'a~
* /^G+vhlf\
* Created on 2007年1月1日, 下午5:01 $7YLU{0
* a$8?0`(
* To change this template, choose Tools | Options and locate the template under b] V=wZ
o
* the Source Creation and Management node. Right-click the template and choose _*I6O$/>
* Open. You can then make changes to the template in the Source Editor. ^O
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*/ yQ50f~9
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package com.tot.count; Y))sk-
import java.util.*; vq:j?7
/** cn:VEF:l
* 1j,Y
* @author p\\q[6
*/ I5?LD=tt
public class CountCache { 9~I WGj?
public static LinkedList list=new LinkedList(); 0in6z
/** Creates a new instance of CountCache */ JN)t'm[kyE
public CountCache() {} W:J00rsv=`
public static void add(CountBean cb){ d*HAKXd&:j
if(cb!=null){ JH#+E04#
list.add(cb); k<H&4Z)d9
} iwJgU
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} ^)~M,rW8c
} %C<eR_
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CountControl.java yr'`~[oSCy
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/* Q2JjBV<
* CountThread.java a mgex$
* U+
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* Created on 2007年1月1日, 下午4:57 rfoCYsX'
* o9>X"5CmX
* To change this template, choose Tools | Options and locate the template under yI<'J^1C[
* the Source Creation and Management node. Right-click the template and choose I|H mbTXa
* Open. You can then make changes to the template in the Source Editor. i,T{SV
*/ +\chHOsw
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package com.tot.count; !ZW0yCwLQ
import tot.db.DBUtils; 1S:H!h3
import java.sql.*; :9Pqy
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/** Fu$sfq
* }.zn:e
* @author jtwO\6 t&
*/ m>_'f{&u
public class CountControl{ i^l;PvIF
private static long lastExecuteTime=0;//上次更新时间 ZxWV,s&p
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Op{Mc$5a
/** Creates a new instance of CountThread */ $@Fj_
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public CountControl() {} ."O(Ig[
public synchronized void executeUpdate(){ ,e,{6Sg6gl
Connection conn=null; <0m;|Ai'W
PreparedStatement ps=null; R?Qou!*]
try{ J:a^''
conn = DBUtils.getConnection(); ZlzFmNe60
conn.setAutoCommit(false); dmO|PswW
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); v5o%y:~
for(int i=0;i<CountCache.list.size();i++){ m/AN*`V
CountBean cb=(CountBean)CountCache.list.getFirst(); O{V"'o
CountCache.list.removeFirst(); qDW/8b\ ^
ps.setInt(1, cb.getCountId()); PdZSXP4;k
ps.executeUpdate();⑴ G'Y|MCKz>
//ps.addBatch();⑵ y6oDbwke
} x&d<IU)5
//int [] counts = ps.executeBatch();⑶ Jo@9f(hq
conn.commit(); l?;S>s*\?
}catch(Exception e){ 5Fl|=G+3@g
e.printStackTrace(); :.,I4>b2
} finally{ ghl9gFFj
try{ .^23qCs
if(ps!=null) { 5`Bb0=j
ps.clearParameters(); @[Th{HTc.G
ps.close(); nj[6c
ps=null; 4]GyuY
} K VCS(oN
}catch(SQLException e){} Z"jo
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DBUtils.closeConnection(conn); N.?Wev{
} gnGw7V
} ~08v]j
q
public long getLast(){ `*a,8M%
return lastExecuteTime; i]v!o$7
} .uP$M(?j
public void run(){ ?0x;L/d])
long now = System.currentTimeMillis(); OZ6%AUot
if ((now - lastExecuteTime) > executeSep) { z$NLFJvy_-
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~ocr^V{"<~
//System.out.print(" now:"+now+"\n"); wHmEt ORo
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); R)=<q]Ms
lastExecuteTime=now; ?:E;C<Ar
executeUpdate(); e(^O8
} D<`X
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else{ -_3.]o/J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); b%BwGS(z
} :vj buqN]
} {~SR>I3sv
} oaHBz_pg
//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 ~EBZlTN
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类写好了,下面是在JSP中如下调用。 2+.m44>Ti
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<% IYWD_}_
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CountBean cb=new CountBean(); A{QS+fa/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Jj!T7f*-GX
CountCache.add(cb); '&Ku Ba
out.print(CountCache.list.size()+"<br>"); (:1j-
CountControl c=new CountControl(); 9SPu 4i
c.run(); |Bid(`t.
out.print(CountCache.list.size()+"<br>"); 0czy:d,M%
%>