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: `cy"-CJS
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CountBean.java yp7,^l
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/* ]mDsUZf<
* CountData.java o2t@-dNi
* 9Y*Vz QE
* Created on 2007年1月1日, 下午4:44 <=LsloI
* TQyFF/K
* To change this template, choose Tools | Options and locate the template under ;/]c^y
* the Source Creation and Management node. Right-click the template and choose /E1c#@
* Open. You can then make changes to the template in the Source Editor. MYW 4@#
*/ 9dhFQWz"
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package com.tot.count; rea}Uq+po
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/** X/C54%T ~
* aABE= 9Y
* @author $y |6<
*/ 2%, ' }Bus
public class CountBean { _}%#Yz
private String countType; ^IegR>
int countId; 97@?QI}
/** Creates a new instance of CountData */ k?*DBXJv
public CountBean() {} ;|e 0{Jrz
public void setCountType(String countTypes){ p9bxhnn|
this.countType=countTypes; b`%e{99\
} YuZ
public void setCountId(int countIds){ ?p\II7
this.countId=countIds; nJ`a1L{N
} D
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public String getCountType(){ Q,+*u%/u
return countType; Z`Eb
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} F1]PYx$X
public int getCountId(){ XzwQ,+IAr
return countId; ~k_zMU-1
} 9YsO+7[
} Gb)iB
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CountCache.java 544I#!
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/* fv7g93
* CountCache.java =1B&d[3;
* tqk6m# @(
* Created on 2007年1月1日, 下午5:01 _ r)hr7
* .j@n6RyN
* To change this template, choose Tools | Options and locate the template under l.'E\3Bo
* the Source Creation and Management node. Right-click the template and choose *y@]zNPD
* Open. You can then make changes to the template in the Source Editor. 4o8HEq!
*/ 8*){*'bf
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package com.tot.count; EjCs
import java.util.*; ZuV
/** nff ]Y$FB
* B{u.Yc:
* @author +*~3"ww<
*/ mq}
#{
public class CountCache { \0& (q%c
public static LinkedList list=new LinkedList(); :Fk&2WsW:
/** Creates a new instance of CountCache */ yUlQPrNX
public CountCache() {} -$p-o
Z)
public static void add(CountBean cb){ ' vClZGQ1
if(cb!=null){ pAL-Pl9z
list.add(cb); !ry+ r!"
} eW<hC(
} JFkjpBS
} 1Tkdr2
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CountControl.java 0w&1wee(
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/* /!3:K<6@
* CountThread.java t,YAk
?}
* Y5pNKL
* Created on 2007年1月1日, 下午4:57 t`{Fnf
* <H#K `|Ag
* To change this template, choose Tools | Options and locate the template under j3F=P
* the Source Creation and Management node. Right-click the template and choose Un+Jz
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* Open. You can then make changes to the template in the Source Editor. wAPdu y[
*/ :.^rWCL2
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package com.tot.count; Qgi:q
import tot.db.DBUtils; l"#,O$x"#@
import java.sql.*; 3 g&mND
/** 1j(,VW
* BW[K/l~"$:
* @author &Gl&m@-j
*/ Czn7,KE8X
public class CountControl{ [?2mt`g
private static long lastExecuteTime=0;//上次更新时间 omu&:)
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 W=:+f)D
/** Creates a new instance of CountThread */ qa6up|xUnn
public CountControl() {} -t?G8,,
public synchronized void executeUpdate(){ c^%k1pae(
Connection conn=null; +UtK2<^:o
PreparedStatement ps=null; egvWPht'_
try{ 9IV WbJ
conn = DBUtils.getConnection(); ?i"FdpW
conn.setAutoCommit(false); Ckp=d
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~Otf
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for(int i=0;i<CountCache.list.size();i++){ Y@eUvz
CountBean cb=(CountBean)CountCache.list.getFirst(); v2Y=vr
CountCache.list.removeFirst(); .}wir,
ps.setInt(1, cb.getCountId()); xOlkG*3c
ps.executeUpdate();⑴ kzu=-@s
//ps.addBatch();⑵ }z#8vE;
} 71InYIed
//int [] counts = ps.executeBatch();⑶ YoA$Gw2
conn.commit(); O&uOm:/(
}catch(Exception e){ Pe.D[]S
e.printStackTrace(); We2=|AB
} finally{ QkbN2mFv%
try{ b;vO`
if(ps!=null) { )g9qkQ 8q
ps.clearParameters(); ;d4_l:9p
ps.close(); hv6>3gbr
ps=null; TEtZPGFl
} |rQ;|+.
}catch(SQLException e){} "]<Ut{Xb
DBUtils.closeConnection(conn); $6N.ykJ
} *0@e_h
} e[n>U@
public long getLast(){ P%c<0y"O:>
return lastExecuteTime; >8Y >B)
} `/O_6PQ}
public void run(){ tP9}:gu
long now = System.currentTimeMillis(); 4Bz~_
if ((now - lastExecuteTime) > executeSep) { Qa=;Elp:[
//System.out.print("lastExecuteTime:"+lastExecuteTime); ?QgWW
//System.out.print(" now:"+now+"\n"); `Cc<K8s8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6 S8#[b
lastExecuteTime=now; 4{TUoI6ii
executeUpdate(); 3c)LBM
} @({65 gJ*
else{ VCI G+Gz
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); LS`Gg7]S
} I/adzLQ
} :3k(=^%G!
} ty ~U~
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 f`Nu]#i
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类写好了,下面是在JSP中如下调用。 \*7Tj-#
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<% C..O_Zn{g
CountBean cb=new CountBean(); s<myZ T$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); W\"cp[b
CountCache.add(cb); Kxg09\5i
out.print(CountCache.list.size()+"<br>"); D_@^XS
CountControl c=new CountControl(); Wl1%BN0>
c.run(); W!{uEH{%l
out.print(CountCache.list.size()+"<br>"); E7N1B*KI
%>