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: ?.SGn[
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CountBean.java ;_I>`h"r
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/* wuH*a3(
* CountData.java Vc(4d-d5
* %^@l5h.lqB
* Created on 2007年1月1日, 下午4:44 {s
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* [7I bT:ph
* To change this template, choose Tools | Options and locate the template under vTK%4=|1}!
* the Source Creation and Management node. Right-click the template and choose O JcS%-~
* Open. You can then make changes to the template in the Source Editor. -wXeue},>
*/ ;qgo=
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package com.tot.count; jsN[Drr a
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/** <Q~N9W
* ,ErfTg&^
* @author 2t\0vV2)/O
*/ =wh[D$n$~
public class CountBean { YCbvCw$Ob
private String countType; *6/IO&y1a
int countId; DzpWU8j
/** Creates a new instance of CountData */ `]5qIKopL
public CountBean() {} tc'iKJ5)
public void setCountType(String countTypes){ bLg!LZ|S0s
this.countType=countTypes; sBadiDG~9
} __g?xw
public void setCountId(int countIds){ C!+D]7\j
this.countId=countIds; x {NBhq(4
} !{-W%=Kf
public String getCountType(){ }h^
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return countType; xrg"/?84
} FDl/7P`b(
public int getCountId(){ @6"MhF
return countId; ?,$:~O*w
} N?qETp -:
} rnK]3Ust
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CountCache.java F7<mm7BGZ
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/* |XB<vj07G
* CountCache.java 8w:ay,=
* wH|%3@eJ
* Created on 2007年1月1日, 下午5:01 J2Dn
* li%@HdA!
* To change this template, choose Tools | Options and locate the template under ZjxF@`H
* the Source Creation and Management node. Right-click the template and choose XCI
* Open. You can then make changes to the template in the Source Editor. ;T^s&/>E
*/ =aVvv+T
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package com.tot.count; _#K|g#p5
import java.util.*; Vo"G@W)lZ
/** ,WE2.MWR
* h{)m}"n<R
* @author M]o]D;N~l
*/ 51ViJdZ
public class CountCache { &0T.o,&y
public static LinkedList list=new LinkedList(); [k
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/** Creates a new instance of CountCache */ dz@+ jEV
public CountCache() {} r^Ra`:ca
public static void add(CountBean cb){ "[
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if(cb!=null){ '
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list.add(cb); 7FH-l(W
}
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} 0gqV>:
} Py*WHHO
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CountControl.java BQfnoF
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/* Sv#MlS>
* CountThread.java 6?,qysm06
* ll5;09
* Created on 2007年1月1日, 下午4:57 IS8 sJ6")
* {U-z(0
* To change this template, choose Tools | Options and locate the template under #_ulmB;
* the Source Creation and Management node. Right-click the template and choose e^*&&
* Open. You can then make changes to the template in the Source Editor. h_t`)]-
*/ vs8[352
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package com.tot.count; MZ%J
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import tot.db.DBUtils; qD%88c)g
import java.sql.*; kVLZdXn,q2
/** \2u7>fU!
* dkg`T#}
* @author OR&pGoW
*/ $/^Y(0
public class CountControl{ ?n<F?~
private static long lastExecuteTime=0;//上次更新时间 *ssw`}yE'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &DGqY5=
/** Creates a new instance of CountThread */ ->qRGUW
public CountControl() {} eLT3b6'"?
public synchronized void executeUpdate(){ =9,mt
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Connection conn=null; YAR$6&
PreparedStatement ps=null; dZ"}wKbO
try{ ~98q1HgS]D
conn = DBUtils.getConnection(); e3n^$'/\r
conn.setAutoCommit(false); ~7aD#`amU
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -0a3eg)Z*
for(int i=0;i<CountCache.list.size();i++){ TS#1+f]9J<
CountBean cb=(CountBean)CountCache.list.getFirst(); bBINjs8C_
CountCache.list.removeFirst(); Z^]Oic/0Oa
ps.setInt(1, cb.getCountId()); s]yZ<uA
ps.executeUpdate();⑴ C=;}7g
//ps.addBatch();⑵ &pl)E$Y
} <O)
if^
//int [] counts = ps.executeBatch();⑶ xe OfofC(l
conn.commit(); )%/ Ni^
}catch(Exception e){ YeJTB}
e.printStackTrace(); FXk*zXn6
} finally{ KdiJ'K.
try{
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if(ps!=null) { 0<A*I{,4L
ps.clearParameters(); k'.cl^6Z8
ps.close(); j}lne^ h
ps=null; + d>2 '
} x15&U\U
}catch(SQLException e){} ;t
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DBUtils.closeConnection(conn); ci%$So2#
} W;Dik%^tg
} R(>
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public long getLast(){ 0(5qVJ12
return lastExecuteTime; 1OY
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} cooicKS7
public void run(){ EP4?+"Z
long now = System.currentTimeMillis(); WO69Wo\C
if ((now - lastExecuteTime) > executeSep) { /5KY6XxR
//System.out.print("lastExecuteTime:"+lastExecuteTime); ?/3{gOgI$`
//System.out.print(" now:"+now+"\n"); rk+s[Qi~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (eT9N_W
lastExecuteTime=now; 1h]nE/T.O
executeUpdate(); CC6]AM(i
} UM1h[#?&V)
else{ }uD*\.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +IGSOWL
} gT fA]
} laCVj6Rk
} }P!:0w3
//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 *wdNZ
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类写好了,下面是在JSP中如下调用。 @gx]3t*]I
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<% .4z_ohe
CountBean cb=new CountBean(); Rs]Y/9F;{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); IYr4
CountCache.add(cb); ,[| i^
out.print(CountCache.list.size()+"<br>"); xs)SKG*
CountControl c=new CountControl(); QF.M%she+
c.run(); #3C]"
out.print(CountCache.list.size()+"<br>"); Urm(A9|N
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