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: 9Glfi@.
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CountBean.java 8j+:s\
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/* 2:HP5
* CountData.java {9|$%4kRl
* J (&M<<%
* Created on 2007年1月1日, 下午4:44 0e:QuV2X
* iMeRQYW
* To change this template, choose Tools | Options and locate the template under 9s6>9hMb)
* the Source Creation and Management node. Right-click the template and choose a2=uM}Hsp
* Open. You can then make changes to the template in the Source Editor. %)hIpxOrX
*/ Or#+E2%1E
#
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package com.tot.count; pT;-1c%:
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/** g*r{!:,t
* VRQbf
* @author [cLU*:
*/ =.f +}y
public class CountBean { >5~Zr$
private String countType; 73s3-DS,
int countId; >[%.h(h/%
/** Creates a new instance of CountData */ z2nUul(2
public CountBean() {} ;'Vipj
public void setCountType(String countTypes){ CMxjX
this.countType=countTypes; 3{I=#>;
} .";tnC!e
public void setCountId(int countIds){ x [{q&N!"`
this.countId=countIds; vu'!-K=0
} SL\y\GaV
public String getCountType(){ XAULD]Q
return countType; lF}$`6
} >upXt?
public int getCountId(){ Aiks>Cyi23
return countId; hKzBq*cV
} *CPB5s
} sg6w7fp>
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CountCache.java E_![`9i
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/* lgjoF_D
* CountCache.java 9p\wTzA
* {7![3`%7
* Created on 2007年1月1日, 下午5:01 o~.o^0Y
* $YGIN7_Gg
* To change this template, choose Tools | Options and locate the template under U3|&Jee
* the Source Creation and Management node. Right-click the template and choose .t^UK#@#4
* Open. You can then make changes to the template in the Source Editor. L4/TI(MP
*/ d0}%%T
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package com.tot.count; _^xh1=Qr}n
import java.util.*; X\3,NR,
/** |!xfIR>=F
* =6Kv`
* @author %M;_(jda
*/ /!{A=N
public class CountCache { +Sd x8 Z5
public static LinkedList list=new LinkedList(); =FD`A#\C~
/** Creates a new instance of CountCache */ ]g8i>,G
public CountCache() {} gM;)
public static void add(CountBean cb){ ;( Ajf.i
if(cb!=null){ gGI#QPT`X
list.add(cb); [nN\{"~O
} \Sq"3_m4T
} Vr/` \441
} UP~WP@0F
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CountControl.java cpF1Xp vT
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/* CNpe8M=/3
* CountThread.java =ve*g&
* .^W\OJ`G
* Created on 2007年1月1日, 下午4:57 {sna)v$;
* y[^k*,=
9
* To change this template, choose Tools | Options and locate the template under ]4 K1%ZV
* the Source Creation and Management node. Right-click the template and choose .n)!ZN
* Open. You can then make changes to the template in the Source Editor. M]4 =(Vv+5
*/ }4\!7]FVYX
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package com.tot.count; C$'D]fX
import tot.db.DBUtils; fZw9zqg
import java.sql.*; 2Pem%HE~P
/** oXQ<9t1(
* =;k+g?.@I
* @author dIk8TJ
*/ fOK+DT~
public class CountControl{ StdS$XW
private static long lastExecuteTime=0;//上次更新时间 XYK1-m}2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 A'~%_}
/** Creates a new instance of CountThread */ f- k|w%R@
public CountControl() {} { /F rs*AF
public synchronized void executeUpdate(){ 0U~;%N+lv
Connection conn=null; :!+}XT7)/
PreparedStatement ps=null; u^aFj%}]L
try{ >2| [EZ
conn = DBUtils.getConnection(); ?x5wS$^q<
conn.setAutoCommit(false); XoKO2<3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )DGz`->
for(int i=0;i<CountCache.list.size();i++){ , N@Yk.
CountBean cb=(CountBean)CountCache.list.getFirst(); x!"SD3r=4>
CountCache.list.removeFirst(); HvqF@/xh
ps.setInt(1, cb.getCountId()); E VN-<=i^
ps.executeUpdate();⑴ uXG`6|?
//ps.addBatch();⑵ ^6)GS%R
} cD'HQ3+
//int [] counts = ps.executeBatch();⑶ jSwtf
conn.commit(); Ss#@=:"P
}catch(Exception e){ |P,zGy
e.printStackTrace(); (
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} finally{ F}6DB*
try{ }XGMa?WR
if(ps!=null) { Z{,GZT
ps.clearParameters(); cQ3W;F8|n
ps.close(); n*vTVt)dJ
ps=null; H{\.g=01
} E(QZ!'%K+m
}catch(SQLException e){} ,?xLT2>J_
DBUtils.closeConnection(conn); 7xv4E<r2
} ,]PyDq6
} `2xH7a-
public long getLast(){ u0bfX,e2U
return lastExecuteTime; ?Do^stq'4
} V-KL%
public void run(){ :jt;EzCLg%
long now = System.currentTimeMillis(); vU_d=T%$
if ((now - lastExecuteTime) > executeSep) { Ow
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//System.out.print("lastExecuteTime:"+lastExecuteTime); mQd4#LJ_
//System.out.print(" now:"+now+"\n"); W>5vRwx00
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,hpH!J'5f/
lastExecuteTime=now; ~ON1Zw[+
executeUpdate(); [x2JFS#4
} ^CZCZ,v
else{ @uI?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F_A%8)N
} h4hN1<ky\
} /9x{^
} 7|&e[@B
//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 X,C*qw@
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类写好了,下面是在JSP中如下调用。 _BZ1Vnv
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<% S~@r
CountBean cb=new CountBean();
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); O1GDugZ
CountCache.add(cb); U@Z>/ q
out.print(CountCache.list.size()+"<br>"); nNt*} k
CountControl c=new CountControl(); +h0PR?
c.run(); YBb)/ZghY
out.print(CountCache.list.size()+"<br>"); #O2wyG)oU
%>