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: Ju5Dd\
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CountBean.java /.s
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/* 6r^ZMW
* CountData.java ?Kmz urG
* %cs"PS
* Created on 2007年1月1日, 下午4:44 wg_Z@iX
* ZYY`f/qi
* To change this template, choose Tools | Options and locate the template under Lww&[|k.
* the Source Creation and Management node. Right-click the template and choose gWro])3
* Open. You can then make changes to the template in the Source Editor. m5/]+xdNX
*/ },<Y
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package com.tot.count; W rT_7
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/** Li8/GoJW-T
* V6>{k_0{V
* @author 1A93ol=
*/ ys)
public class CountBean { a^G>|+8
private String countType; ']Czn._
int countId; H [M:iV
/** Creates a new instance of CountData */ vh|m[ p
public CountBean() {} .: wg@Z
public void setCountType(String countTypes){ oGXcu?ft
this.countType=countTypes; C(sz/x?11
} ]}S9KP
public void setCountId(int countIds){ Z3<lJk\Y
this.countId=countIds; !#1UTa
} g\+!+!"~
public String getCountType(){ xhCNiYJ|
return countType; Yjy%MR
} J>hjIN
public int getCountId(){
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return countId; SXXO#
} }WR@%)7ay
} V[8!ymi0
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CountCache.java +CQIm!Sp
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/* EE9eG31|r
* CountCache.java t|&hXh{
*
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* Created on 2007年1月1日, 下午5:01 .^- I<4 .
* FIJ]`
* To change this template, choose Tools | Options and locate the template under SbtZhg=S_
* the Source Creation and Management node. Right-click the template and choose SQ/}K8uZ
* Open. You can then make changes to the template in the Source Editor. V+u0J"/8
*/ %~dn5t;
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package com.tot.count; gxDyCL$h3
import java.util.*; )Zvn{
/** p%Ns
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* r-hb]!t
* @author x` 4|^u
*/ KrTlzbw&p\
public class CountCache { 1LmbXH]%
public static LinkedList list=new LinkedList(); u\K`TWb%
/** Creates a new instance of CountCache */ Q9g^'a
public CountCache() {} L$]Y$yv
public static void add(CountBean cb){ CT.hBz
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if(cb!=null){ B.?@VF
list.add(cb); Q2gz\N
} [L2N[vy;
} EP{ji"/7[
} }o=s"0 a
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CountControl.java Mn*v&O :
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/* m4 c2WY6k
* CountThread.java O2~Q(q'
* ;k=`J
* Created on 2007年1月1日, 下午4:57 ,u5iiR
* ]%(X}]}
* To change this template, choose Tools | Options and locate the template under _]kw |[)
* the Source Creation and Management node. Right-click the template and choose 8$ _8Yva"e
* Open. You can then make changes to the template in the Source Editor. zrA=?[
*/ !$0ozDmD
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package com.tot.count; F,xFeq$/{
import tot.db.DBUtils; ?2S<D5MSb
import java.sql.*; GS,}]c=
/** %PM8;]
* qD(dAU
* @author Mgux(5`;
*/ ;+~Phdy
public class CountControl{ 9d+z?J:
private static long lastExecuteTime=0;//上次更新时间 ~#:R1~rh\e
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :D
/** Creates a new instance of CountThread */ E#yG}UWe
public CountControl() {} Wl{}>F`W[
public synchronized void executeUpdate(){ Gr|102
Connection conn=null; HA;G{[X
PreparedStatement ps=null;
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try{ KD8,a+GL
conn = DBUtils.getConnection(); cx+%lco!
conn.setAutoCommit(false); ! ?GW<Rh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s,8g^aF4
for(int i=0;i<CountCache.list.size();i++){ l\&Tw[O
CountBean cb=(CountBean)CountCache.list.getFirst(); gYa
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CountCache.list.removeFirst(); #D Oui]
ps.setInt(1, cb.getCountId()); 4nD U-P#f
ps.executeUpdate();⑴ ;<s0~B#9}
//ps.addBatch();⑵ $+w -r#,
} &}b-aAt
//int [] counts = ps.executeBatch();⑶ a(K^/BT
conn.commit(); q=/ck
}catch(Exception e){ 71k>_'fl
e.printStackTrace(); ka| 8 _C^z
} finally{ tQ(gB_
try{ `j(-y`fo
if(ps!=null) { lm(k[]@
ps.clearParameters(); )uH#+IU
ps.close(); ;c0z6E /
ps=null; f26hB;n
} b,-qyJW6
}catch(SQLException e){} S!.H _=z%p
DBUtils.closeConnection(conn); 8i?:aN[.1b
} R}0!F2
} McRfEF\
public long getLast(){ {h}e 9
return lastExecuteTime; wT^Q O^.
} 3W"l}.&ZJ"
public void run(){ F@kd[>/[
long now = System.currentTimeMillis(); Huho|6ohH
if ((now - lastExecuteTime) > executeSep) { .L))EB
//System.out.print("lastExecuteTime:"+lastExecuteTime); sB%QqFRP
//System.out.print(" now:"+now+"\n"); pcO0xrI
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); T8-,t];i
lastExecuteTime=now; ffoLCx4o0E
executeUpdate(); H 5'Ke+4.e
} Ce!xa\
else{ J=AF`[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); E@92hB4D"
} \LQ54^eB
} 45$FcK
} MXGz_Db4'
//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 h5VZ-v_j
#m36p+U
类写好了,下面是在JSP中如下调用。 _jD\kg#LY
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<% "P@oO,.
CountBean cb=new CountBean(); |Y]4PT#EE
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?Y\hC0a60
CountCache.add(cb); [X\~J &kD
out.print(CountCache.list.size()+"<br>"); p1B~F
CountControl c=new CountControl(); wJu,N(U
c.run(); KkD&|&!Q7u
out.print(CountCache.list.size()+"<br>"); 9 Aq\1QC
%>