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: .dM4B'OA?
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CountBean.java }22h)){n#Y
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/* 90<z*j$EK
* CountData.java ~U"puEftbs
* b/"&E'5-`\
* Created on 2007年1月1日, 下午4:44 "V|&s/9
*
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* To change this template, choose Tools | Options and locate the template under mu`:@7+Yp
* the Source Creation and Management node. Right-click the template and choose P`^3-X/
* Open. You can then make changes to the template in the Source Editor. T)4pLN
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*/ CNP!v\D
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package com.tot.count; t,H=;U#
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/** <Cv6wC=
* R2K{vs
* @author B'[FnJ8~
*/ \MhSIlM#
public class CountBean { ,,
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private String countType; F%|F-6
int countId; PiQsVk
/** Creates a new instance of CountData */ P?WS=w*O0
public CountBean() {} .t53+<A
public void setCountType(String countTypes){ -(~OzRfYi
this.countType=countTypes;
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} dZMf5=tb
public void setCountId(int countIds){ 3(&f!<Uy
this.countId=countIds; <cig^B{nX
} Uphme8SX
public String getCountType(){ $>if@}u
return countType; VDy2!0
} Kd,8PV*_
public int getCountId(){ #POVu|Y;h
return countId; :[P)t
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} 7# !RX3
} Ov<EOK+^
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CountCache.java >`{B
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/* `_;sT8
* CountCache.java WZh%iuI{C
* L<dJWxf?D
* Created on 2007年1月1日, 下午5:01 >G#SfE$0
* WlJ=X$
* To change this template, choose Tools | Options and locate the template under X>-|px$vy
* the Source Creation and Management node. Right-click the template and choose k4i*80
* Open. You can then make changes to the template in the Source Editor. o*5iHa(Qm
*/ xOY
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package com.tot.count; mc
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import java.util.*; p<[gzmU9\b
/**
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* PPpq"c
* @author B
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*/ !{S& "
public class CountCache { Xg4iH5!E
public static LinkedList list=new LinkedList(); MJ.K,e
/** Creates a new instance of CountCache */ Z(h.)$yH*=
public CountCache() {} Wxeg(L}E
public static void add(CountBean cb){ t@"i/@8x$
if(cb!=null){ arWP]%E0W
list.add(cb); s^\
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} A.YXK%A%
} E&z`BPd
} Vf*Z }'
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CountControl.java S&JsDPzSd
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/* WgTD
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* CountThread.java y]U]b G{
* _A/q bm
* Created on 2007年1月1日, 下午4:57 r `;_ #&b
* j:>_1P/
* To change this template, choose Tools | Options and locate the template under 9'"
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* the Source Creation and Management node. Right-click the template and choose _ J t
* Open. You can then make changes to the template in the Source Editor. ?zP/i(1y
*/ xCTPsw]s
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package com.tot.count; -Z(='A
import tot.db.DBUtils; j0wpaIp
import java.sql.*; |d)*,O4s
/** Q4R*yRk
* R\T1R"1
* @author Q\moR^>
*/ _uf,7R-
public class CountControl{ DWwPid}
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private static long lastExecuteTime=0;//上次更新时间 hj4mbL
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;udV"7C
/** Creates a new instance of CountThread */ ~[@gu,Wb
public CountControl() {} w\}@+w3b~
public synchronized void executeUpdate(){ GZt L-
Connection conn=null; %iq8dAW%
PreparedStatement ps=null; \#(tI3
try{ &02I-lD4+
conn = DBUtils.getConnection(); +x(~!33[G
conn.setAutoCommit(false); Y#<>N-X|kA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); A||,|He~
for(int i=0;i<CountCache.list.size();i++){ 6"djX47j
CountBean cb=(CountBean)CountCache.list.getFirst(); AY x*Ngn
CountCache.list.removeFirst(); P]^BE;7T
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ 1Qk]?R/DN
//ps.addBatch();⑵ ,L&d\M"f
} ^ h?]$P
//int [] counts = ps.executeBatch();⑶ Rp0`%}2
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conn.commit(); ]#sF
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}catch(Exception e){ EA``G8Vn>
e.printStackTrace(); S HxD(6
} finally{ rNN,!
try{ , G2(l
if(ps!=null) { % B^BN|r
ps.clearParameters(); xf4CM,Z7(
ps.close(); IzI2w6a
ps=null; UP .4# 1I
} dMw}4c3E
}catch(SQLException e){} |>zYUT[V
DBUtils.closeConnection(conn); /6{P
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} 93VbB[w~7F
} +R2+?v6
public long getLast(){ K6EG"Vv!
return lastExecuteTime; :\F1S:&P
} <Toy8-kj
public void run(){ }h+{>{2j
long now = System.currentTimeMillis(); q@&6&cd
if ((now - lastExecuteTime) > executeSep) { 1:;S6{oQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); &V(;zy4(R
//System.out.print(" now:"+now+"\n"); ua!43Bp
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); j"r7M|Z+V
lastExecuteTime=now; JKTn
executeUpdate(); ^xX1G_{
} 6o)RsxN eu
else{ )#l&BV5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -P:o ^_)g
} S;^'Ek"Z.
} @%"r69\
} 6an= C_Mb`
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 =Cc]ugl7-
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类写好了,下面是在JSP中如下调用。 GS&I6
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<% QV[#^1
CountBean cb=new CountBean(); ,4HZ-|EOZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); puAjAvIax
CountCache.add(cb); |)*9BN
out.print(CountCache.list.size()+"<br>"); {,B.OM)J
CountControl c=new CountControl(); e<$s~ UXv
c.run(); ^{Fo,7
out.print(CountCache.list.size()+"<br>"); RxE.t[
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