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: 3+d^Bpp4
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CountBean.java u9~Ncz
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/* QRKP;aYt
* CountData.java E<u(Yw6=
* }fkdv6mz
* Created on 2007年1月1日, 下午4:44 ,Nhv#U<$
* E3[9!L8gb
* To change this template, choose Tools | Options and locate the template under Pi |Z\j)
* the Source Creation and Management node. Right-click the template and choose ?u:mscb
* Open. You can then make changes to the template in the Source Editor. HWB\}jcA6u
*/ !jU{ }RCR
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package com.tot.count; sb3z8:r
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/** 3fpaTue|x
* ]+a~/
* @author zA+0jhuG
*/ O;V^Fk(
public class CountBean { ~xc/Dsb$
private String countType; &[j9Up'
int countId; C@t,oDU#
/** Creates a new instance of CountData */ xr@;w8X`^
public CountBean() {} V_m!<sr (
public void setCountType(String countTypes){ 60nP'xfR
this.countType=countTypes; Opg_-Bf
} >eo[)Y
public void setCountId(int countIds){ ||TZ[l
this.countId=countIds; ):Z#!O<
}
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public String getCountType(){ bc~WJ+
return countType; pV(Mh[ }P
} /U!B2%vq_
public int getCountId(){ +aM[!pW(e
return countId; _=`DzudE
} W.cc!8
} $8 &Y(`
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CountCache.java -zJV(`
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/* [*(1~PrlO,
* CountCache.java 1BW 9,Xr
* edcz%IOM(
* Created on 2007年1月1日, 下午5:01 D*VO;?D
* ntPj9#lf
* To change this template, choose Tools | Options and locate the template under +$VDV4l
* the Source Creation and Management node. Right-click the template and choose u{\>iQ
* Open. You can then make changes to the template in the Source Editor. W)D?8*
*/ (;05=DsO
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package com.tot.count; H<q|je}e
import java.util.*; I9aiAD0s
/** 09P2<oFLn
* u9,dSR
* @author 1'(";
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*/ d/Wp>A@dob
public class CountCache { W-|CK&1
public static LinkedList list=new LinkedList(); <P0 P*>M
/** Creates a new instance of CountCache */ TJW8 l[M
public CountCache() {} *HHL a
public static void add(CountBean cb){ [:(O`#
if(cb!=null){ K
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list.add(cb); [PiMu,O[v
} SEg{Gso9b
} we!w5./Xm
} g$"x,:2x{
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CountControl.java F !OD*]
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/* :6)!#q'g
* CountThread.java ZBx,'ph}4
* F 2zUz[
* Created on 2007年1月1日, 下午4:57 X6$Cd]MN
* kCz2uG)l
* To change this template, choose Tools | Options and locate the template under ;=^J_2ls
* the Source Creation and Management node. Right-click the template and choose "SQyy
* Open. You can then make changes to the template in the Source Editor. NJd4( P
*/ VyYrL]OrA
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package com.tot.count; HGh)d` 8
import tot.db.DBUtils; nSQ]qH&4d
import java.sql.*; |E$q S)y
/** }W!w
* *sB'D+-/
* @author +lFBH(o]X
*/ /u90)x
public class CountControl{ (vi^ t{k
private static long lastExecuteTime=0;//上次更新时间 y,1U]1TP
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,|?#+O{
/** Creates a new instance of CountThread */ x5smJ__/
public CountControl() {} lB/^
public synchronized void executeUpdate(){ ;*FY+jM
Connection conn=null; |9$C%@8
PreparedStatement ps=null; -"2 t^Q
try{ Yc~l Yz+b
conn = DBUtils.getConnection(); z(O*DwY#
conn.setAutoCommit(false); *0L3#. i
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `}uM91;
for(int i=0;i<CountCache.list.size();i++){ d!Y%7LmSE@
CountBean cb=(CountBean)CountCache.list.getFirst(); yV L >Ie/
CountCache.list.removeFirst(); .8ikcs
ps.setInt(1, cb.getCountId()); ^!k_"C)B
ps.executeUpdate();⑴ a Iyzt
//ps.addBatch();⑵ 1B&XM^>/
} Mg8ciV}\xY
//int [] counts = ps.executeBatch();⑶ l<S3<'&
conn.commit(); $I#~<bW,
}catch(Exception e){ Rc D5X{qS#
e.printStackTrace(); fwzyCbks
} finally{ Bonj K#
try{ ngd4PN>{4
if(ps!=null) { i
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ps.clearParameters(); zp'hA
ps.close(); ?;5/"/i
ps=null; |d6/gSiF
} Kc1w[EQ
}catch(SQLException e){} fo/sA9
DBUtils.closeConnection(conn); Y Kp@n8A
} L.K| ]]u
} a5pM ~.]
public long getLast(){ pK_zq
return lastExecuteTime; rij%l+%@#
} ~mah.8G
public void run(){ F/tRyq`D
long now = System.currentTimeMillis(); Wie0r@5E
if ((now - lastExecuteTime) > executeSep) { F8tMZ,:
//System.out.print("lastExecuteTime:"+lastExecuteTime); .ty2! .
//System.out.print(" now:"+now+"\n"); 5RO6YxQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ).u>%4=6
lastExecuteTime=now; /Hm/%os
executeUpdate(); /J!hKK^k
} &pz`gna
else{ 3?h!nVI+2J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); g3%x"SlIU
} TI"Ki$jC
} C deV3
} efHCPj
//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 >k=@YLj
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类写好了,下面是在JSP中如下调用。 !&@t
#jj(S\WY
<% [-e$4^+9
CountBean cb=new CountBean(); 3qNuv];2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =Bh,>Kg
CountCache.add(cb); G$Fo*;Fl
out.print(CountCache.list.size()+"<br>"); Jzy:^PObT
CountControl c=new CountControl(); $SFreyI;Uf
c.run(); ]eFNR1<OP
out.print(CountCache.list.size()+"<br>"); #zSNDv`
%>