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: _t;w n7p
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CountBean.java BO
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/* Hss{Sb(
* CountData.java %%k[TO
* np>*O }r*
* Created on 2007年1月1日, 下午4:44 jgGn"}
* 2G'G45Q
* To change this template, choose Tools | Options and locate the template under +>:X4A*
* the Source Creation and Management node. Right-click the template and choose ;\&7smE[
* Open. You can then make changes to the template in the Source Editor. T Z>z5YTv
*/ ^d2g"L
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package com.tot.count; f O(.I
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/** T:}Ed_m}q
* 1MV^~I8Dd
* @author G3OQbqn
*/ < )?&Jf>_
public class CountBean { J J3vC
private String countType; i&bttSRNV
int countId; Dl"y|
/** Creates a new instance of CountData */ qK#* UR0%
public CountBean() {} .#Sd|C]R7
public void setCountType(String countTypes){ 8;Pdd1GyUL
this.countType=countTypes; (ZI&'"H
} cdGl[dQ/
public void setCountId(int countIds){ 0 /H1INve
this.countId=countIds; 1zp,Suv
} }h]:I'R!
public String getCountType(){ 6 8_UQ.
return countType; )0'O!O
} <A6<q&g|E
public int getCountId(){ "3>#[o
return countId; 5VPuHY2
} 6>vj({,1Y*
} 0<Pe~i_=
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CountCache.java i2!{.*.
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/* $jntT(V
* CountCache.java ,Y5+UzE@
* )1i)I?m
* Created on 2007年1月1日, 下午5:01 O'mX7rY<<(
* lq9c2xK
* To change this template, choose Tools | Options and locate the template under (>Yii_Cd
* the Source Creation and Management node. Right-click the template and choose B}!n6j`
* Open. You can then make changes to the template in the Source Editor. 97&6i TYA
*/ |LjCtm)@+
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package com.tot.count; kO9yei
import java.util.*; >l7
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/** cCj3,s/p
* 4u&l@BUr
* @author x*)Wl!
*/ lW2qVR
public class CountCache { odhgIl&u
public static LinkedList list=new LinkedList(); sy#Gb#=#
/** Creates a new instance of CountCache */ yqYX<<!V
public CountCache() {} RoiMvrJQP
public static void add(CountBean cb){ =kCpCpET
if(cb!=null){ 9\n}!{@i
list.add(cb); 8uu:e<PLv
} >\i{,F=U7
} 0-#ct1-
} rms&U)?
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CountControl.java REsThB
" DFg"
/* fklMYu4:n
* CountThread.java iy4JI,-W
* (;M"'.C
* Created on 2007年1月1日, 下午4:57 cCeD3CuRA%
* ov+qYBuFw
* To change this template, choose Tools | Options and locate the template under mR{0*<
* the Source Creation and Management node. Right-click the template and choose k |Lm;g
* Open. You can then make changes to the template in the Source Editor. c8Opc"UE
*/ {B}0LJIpL
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package com.tot.count; ,L^L uw'7
import tot.db.DBUtils; Z*Y?"1ar
import java.sql.*; pp-Ur?PM
/** [Q*kom :
* Gah e-%J
* @author Kfr?sX
*/ N" 8o0>
public class CountControl{ aL`pvsnF
private static long lastExecuteTime=0;//上次更新时间 t3WlVUtq3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 L\B+j+~
/** Creates a new instance of CountThread */ ]x Kmz
public CountControl() {} uu/MXID
public synchronized void executeUpdate(){ B\mdOTLQ
Connection conn=null; p$=3&qR 6
PreparedStatement ps=null; FStfGN
try{ +Q '|->#
conn = DBUtils.getConnection(); L%<1C\k
conn.setAutoCommit(false); i a|F
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); urN&."c
for(int i=0;i<CountCache.list.size();i++){ 2<O
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CountBean cb=(CountBean)CountCache.list.getFirst(); ?+!KucTF
CountCache.list.removeFirst(); W)"q9(T?%
ps.setInt(1, cb.getCountId()); C&SYmYj^c
ps.executeUpdate();⑴ HR}c9wy,q\
//ps.addBatch();⑵ AsLAm#zq
} |p+VitM7
//int [] counts = ps.executeBatch();⑶ +X&B'
conn.commit(); Ry(!<w,
}catch(Exception e){ qd.b&i
e.printStackTrace(); PM|K*,3J
} finally{ aR\=p:%jGI
try{ ;js7rt
if(ps!=null) { [sad}@R7
ps.clearParameters(); IS!+J.2
ps.close(); z~W@`'f
ps=null; -R8RAwsLG
} a[u8x mH
}catch(SQLException e){} Zf"AqGP
DBUtils.closeConnection(conn); ooq>/OI0
} 8O7JuR
} '"TBhisky
public long getLast(){ 99eS@}RC
return lastExecuteTime; l^vq'<kI
} }Bb(wP^B.
public void run(){ LY|h*a6Ym
long now = System.currentTimeMillis(); J^W.TM&q$,
if ((now - lastExecuteTime) > executeSep) { SUx0!_f*R
//System.out.print("lastExecuteTime:"+lastExecuteTime); q4Z\y
//System.out.print(" now:"+now+"\n"); wS5hXTb"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); AiyjrEa%
lastExecuteTime=now; qV}zV\Nz
executeUpdate(); F3qi$ 3HM
} !pN,,H6Y
else{ s4Wk2*7Mq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z[';HJ0O;
} gC3{:MC-G
} qmK!d<4
} ;?y?s'>t&
//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 +-oXW>`&
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类写好了,下面是在JSP中如下调用。 "qF&%r'
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<% dRu@5
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CountBean cb=new CountBean(); I8[G!u71)_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1jV^\x0
CountCache.add(cb); 5~sJ$5<,
out.print(CountCache.list.size()+"<br>"); S<>e(x3g]
CountControl c=new CountControl(); :&a|8Wi[W
c.run(); $$8"i+,K
out.print(CountCache.list.size()+"<br>"); "16==tLFE
%>