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: 6KD `oUx
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CountBean.java [:xiZ
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/* KIR'$ 6pn~
* CountData.java f;/QJ
* [V4 {c@
* Created on 2007年1月1日, 下午4:44 *),8PoT
* OB[o2G <0
* To change this template, choose Tools | Options and locate the template under 'n<iU st
* the Source Creation and Management node. Right-click the template and choose jp $Z]
* Open. You can then make changes to the template in the Source Editor. 763+uFx^
*/ &/Ro lIHF
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package com.tot.count; gp$Ucfu'
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/** ,K:ll4{b
*
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* @author kId
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*/ A
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public class CountBean { .uNQBBNv
private String countType; G_> #Js
int countId; _+
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/** Creates a new instance of CountData */ o)OUWGjb/K
public CountBean() {} qlA7tU2p&
public void setCountType(String countTypes){ k`GA\&zt
this.countType=countTypes; >~K
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} oI^4pwn h
public void setCountId(int countIds){ VCtH%v#S;.
this.countId=countIds; PjN =k;
} +7t6k7]c
public String getCountType(){ "5eNLqt^q
return countType; Q}S_%I}u:
} }(egMx;"3J
public int getCountId(){ {O|'U'
return countId;
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} 0rGSH*(
} ' B
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CountCache.java Me6+~"am/
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/* c)@>zto#
* CountCache.java c5|:,wkx
* "B_K
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* Created on 2007年1月1日, 下午5:01 cUDoN`fSl,
* V/LQ<Yke
* To change this template, choose Tools | Options and locate the template under RT>{*E<I
* the Source Creation and Management node. Right-click the template and choose U%h);!<
* Open. You can then make changes to the template in the Source Editor. rHP%0f9:
*/ V7TVt,-3
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package com.tot.count; tgjr&G}a@0
import java.util.*; _z[#}d;k
/** P ~PIMkt
* o[H{(f1%
* @author %F kMv
*/ v\`9;QV5
public class CountCache { p-+K4
public static LinkedList list=new LinkedList(); 8EVgoJ.
/** Creates a new instance of CountCache */ BL 3gKx.'
public CountCache() {} a,78l@d(
public static void add(CountBean cb){ *m2=/Sh
if(cb!=null){ *Z_C4Tj
list.add(cb); iMfngIs |
} XJ2^MF2BU
} kh%{C]".1
} jYiv'6z
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CountControl.java Z'H5,)j0R
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/* pIbdN/z
* CountThread.java wO2_DyMm@
* nYbhy}y
* Created on 2007年1月1日, 下午4:57 $ "Bh]-
* pHoEa7:
* To change this template, choose Tools | Options and locate the template under 4nAa`(62
* the Source Creation and Management node. Right-click the template and choose 7} jWBK
* Open. You can then make changes to the template in the Source Editor. !ZU2{
*/ c$wsH25KH8
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package com.tot.count; h[Gg}N!
import tot.db.DBUtils; \P1=5rP
import java.sql.*; WoxwEi1~0
/** 0j C3fT!n
* M`6y@<
* @author h5yzwj:C?
*/ :UJ a&$)
public class CountControl{ m~uOXb
private static long lastExecuteTime=0;//上次更新时间 y*MF&mQ[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 f@co<iA
/** Creates a new instance of CountThread */ %p
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public CountControl() {} gNG r!3*)w
public synchronized void executeUpdate(){ g R
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Connection conn=null; t#!yrQ..'G
PreparedStatement ps=null; ["}rk
try{ T)\"Xj
conn = DBUtils.getConnection(); k? Xc
conn.setAutoCommit(false); 3OM2Y_
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W-/}q0h
for(int i=0;i<CountCache.list.size();i++){ vd6l7"0/
CountBean cb=(CountBean)CountCache.list.getFirst(); vf4{$Oag
CountCache.list.removeFirst(); Q]o C47(
ps.setInt(1, cb.getCountId()); ItVugI(^ C
ps.executeUpdate();⑴ $H$j-)\D
//ps.addBatch();⑵ -|rLs$V1r
} !;_H$r0
//int [] counts = ps.executeBatch();⑶ `-3o+ID\
conn.commit(); -X+H2G
}catch(Exception e){ wb Iq&>p
e.printStackTrace(); kF>o.uSV
} finally{ $wYFEz
try{ >hH0Q5aL
if(ps!=null) { ,ZS6jZ
ps.clearParameters(); !a$ D4(`v
ps.close(); mXUYQ82
ps=null; -Z-IF#%
} ](F#`zUQ
}catch(SQLException e){} -R>}u'EG>
DBUtils.closeConnection(conn); Lr`1TH,
} {647|j;e
} &F}"Z(B<wK
public long getLast(){ ^uJU}v:
return lastExecuteTime; L,;D@Xi
} N N|u _
public void run(){ yPw'] "
long now = System.currentTimeMillis(); Tlj:%yK2
if ((now - lastExecuteTime) > executeSep) { fm~kM
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//System.out.print("lastExecuteTime:"+lastExecuteTime); 7RDDdF E!
//System.out.print(" now:"+now+"\n"); eiJ2NwR\w
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); wM_c48|d
lastExecuteTime=now; hXGwP4
executeUpdate(); /*Qq[C
} XlI!{qj|
else{ R}mn*h6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8>/Q1(q0
} #P#-xz
} b|zg<
} Z!0]/ mCE8
//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 lcV<MDS
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类写好了,下面是在JSP中如下调用。 &uUo3qXQ5l
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<% Ap{}^
CountBean cb=new CountBean(); G|8%qd
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .WQ<jZt>
CountCache.add(cb); ,<DB&&EV8
out.print(CountCache.list.size()+"<br>"); (z$r :p
CountControl c=new CountControl(); ~ d^<_R
c.run(); ;6
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out.print(CountCache.list.size()+"<br>"); .Wi{lt
%>