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: e@I?ESZ5
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CountBean.java ^KlMBKWyB
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/* nE/T)[1|
* CountData.java t`Hwq
* xpSMbX{e
* Created on 2007年1月1日, 下午4:44 {v2Q7ZO-
* sRYFu%
* To change this template, choose Tools | Options and locate the template under K}a[ ~
* the Source Creation and Management node. Right-click the template and choose Z7%>O:@z
* Open. You can then make changes to the template in the Source Editor. `aSz"4Wd
*/ Ag?@fuk$J
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package com.tot.count; \hm=AGI0
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/** /Wzic+v<>
* SM@1<OCc
* @author O(!wDnhc
*/ Os[^ch
public class CountBean { ;=_KLG <
private String countType; IJ=~hBI
int countId; FC)aR[
/** Creates a new instance of CountData */ &&t4G }*
public CountBean() {} Dj %jrtT
public void setCountType(String countTypes){ ?BLd~L+
this.countType=countTypes; kOkgsQQ
} o[8Y %3
public void setCountId(int countIds){ H!vvdp?Z
this.countId=countIds; >Y[{m $-
} 1UmV&
public String getCountType(){ o&X!75^G>
return countType; kw1PIuz4&
} < FN[{YsA
public int getCountId(){ ! .!qJ%
return countId; C96|T>bk
} .|_+>){$w
} rK"$@tc
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CountCache.java JQ0KXS Nr
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/* Bz]64/
* CountCache.java F"9qBl~
* tn:9
* Created on 2007年1月1日, 下午5:01
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* V!~uGf
* To change this template, choose Tools | Options and locate the template under W;,Jte<'Nm
* the Source Creation and Management node. Right-click the template and choose KcY 2lTvx
* Open. You can then make changes to the template in the Source Editor. jaNkWTm:
*/ ))AjX
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package com.tot.count; xe%+Yb]
import java.util.*; I`FH^=
/** L5PN]<~T
* P 7gS
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* @author JYKaF6bx8
*/ 0oM~e
public class CountCache { }CQ GvH
public static LinkedList list=new LinkedList(); iF<VbQP=X^
/** Creates a new instance of CountCache */ <A!v'Y
public CountCache() {} jcevpKkRG
public static void add(CountBean cb){ MiS$Y
if(cb!=null){ C8aYg
list.add(cb); 4qiG>^h9
} &Du!*V4A
} t;ggc{
} VNA VdP
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CountControl.java hPhN7E03
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/* ']4sx_)S
* CountThread.java MW`q*J`Yo
* M~P}80I
* Created on 2007年1月1日, 下午4:57 V#5BZU-
* ~Kt.%K5lgt
* To change this template, choose Tools | Options and locate the template under }vp\lKP
* the Source Creation and Management node. Right-click the template and choose <7u*OYjA
* Open. You can then make changes to the template in the Source Editor. _
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*/ !^B`7
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package com.tot.count; RqH"+/wR
import tot.db.DBUtils; Rs5G5W@"A
import java.sql.*; nj
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/** &!m;s_gi
* Fi1gM}>py
* @author Nluy]h
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*/ 6g( 2O[n.
public class CountControl{ WG(tt.
private static long lastExecuteTime=0;//上次更新时间 U%j=)VD])
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 O"_FfwO
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/** Creates a new instance of CountThread */ @[.%A;E4
public CountControl() {} 64`V+Hd
public synchronized void executeUpdate(){ rzEE |
Connection conn=null; t$R|lv5<
PreparedStatement ps=null; wnhac}
try{ w^z}!/"]u
conn = DBUtils.getConnection(); #OH# &{H
conn.setAutoCommit(false); b pExYyt
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); wrw~J
for(int i=0;i<CountCache.list.size();i++){ s+o/:rrxY
CountBean cb=(CountBean)CountCache.list.getFirst(); 0SA
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CountCache.list.removeFirst(); `<C)oF\~f
ps.setInt(1, cb.getCountId()); k}Ahvlq)
ps.executeUpdate();⑴ "4}{Z)&R2
//ps.addBatch();⑵ d];E99}
} Hi<{c
//int [] counts = ps.executeBatch();⑶ rEs,o3h?po
conn.commit(); 0|P RCq
}catch(Exception e){ ,Q >u
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e.printStackTrace(); 4k<4=E
} finally{ xHe<TwkI
try{ uRwIxT2
if(ps!=null) { {i`BDOaL
ps.clearParameters(); g:O~1jq
ps.close(); ImyB4welo
ps=null; j<wWPv
} KS3
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}catch(SQLException e){} YD7i6A
DBUtils.closeConnection(conn); v-_K'm
} `R=8=6Z+$q
} <~vamim#K
public long getLast(){ F;5.nKo
return lastExecuteTime; }3 RqaIY}
} = w_y<V4
public void run(){ X=mzo\Aos
long now = System.currentTimeMillis(); +n9]c~g!T0
if ((now - lastExecuteTime) > executeSep) { 0KU,M+_
//System.out.print("lastExecuteTime:"+lastExecuteTime); )z$VQ=]"
//System.out.print(" now:"+now+"\n"); uFL~^vz
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7*~
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lastExecuteTime=now; w\8grEj
executeUpdate(); Cf
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} xG\&QE
else{ *ZF7m_8u{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); fQ'P2$
} (X QgOR#
} &
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} ?L+@?fVN
//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 a]BnHLx
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类写好了,下面是在JSP中如下调用。 K zKHC
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<% HG5|h[4Gt
CountBean cb=new CountBean(); 0:Yz'k5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c7L#f=Ot?
CountCache.add(cb); >}43MxU?
out.print(CountCache.list.size()+"<br>"); V[uB0#Lp
CountControl c=new CountControl(); \y"!`.E7\d
c.run(); TOeJnk
out.print(CountCache.list.size()+"<br>"); c+Ejah+
%>