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: o6d x\
fT|A^
CountBean.java ,/D}a3JD
Z*q9vX
/* gf1+yJ^d!
* CountData.java Dlq!:dF{&
* KWZhCS?[(
* Created on 2007年1月1日, 下午4:44 Zym6btc
* qh:Bc$S
* To change this template, choose Tools | Options and locate the template under 2lCFE)
* the Source Creation and Management node. Right-click the template and choose 3f] ;y<Km
* Open. You can then make changes to the template in the Source Editor. QYboX~g~p
*/ =29IHL3
j/z=<jA
package com.tot.count; >m>F {v
ca{MJz'
/** w?8SQI,~X
* ;~EQS.Qp
* @author )](ls@*
*/ I5_HaC>
public class CountBean { /\c'kMAW!
private String countType; O=A2QykV(
int countId; $2Whb!7Z(
/** Creates a new instance of CountData */ 4P&2Z0
public CountBean() {} \3$!) z
public void setCountType(String countTypes){ u3C_Xz
this.countType=countTypes; RqtBz3v
} eHy UY&N/
public void setCountId(int countIds){ U}RBgPX!
this.countId=countIds; &ASR2J
} y
%Q. (
public String getCountType(){ #cu{AdK
return countType; _cX}!d!j
} z*EV>Y[
public int getCountId(){ y:W6;R
return countId; V0=%$tH
} ];OvV ,*
} gvA}s/
Dz(\ ?
CountCache.java S^eem_C
5e/YEDP
/* x,!Dd
* CountCache.java 1)56ec<c
* sD:o
2(G*
* Created on 2007年1月1日, 下午5:01 UX@%1W!8
* Lwr's'ao.
* To change this template, choose Tools | Options and locate the template under ^_;'9YD
* the Source Creation and Management node. Right-click the template and choose wqb4w7%
* Open. You can then make changes to the template in the Source Editor. ^$K&Met
*/ Yv5H41o"
u4C9ZYN
package com.tot.count; *Jd"3Si/
import java.util.*; _&uJE&xl}
/** #h5lz%2g
* `RL
Wr,h
* @author uiVNz8H
*/ "lI-/G
public class CountCache { V4:/LNq_]
public static LinkedList list=new LinkedList(); Io1j%T#ZT
/** Creates a new instance of CountCache */ 7nek,8b
public CountCache() {} HIXAA?_eh=
public static void add(CountBean cb){ JWixY/
if(cb!=null){ ^#HaH
list.add(cb); #ES[),+|mB
} H<(F$7Q!\
} p~ b4TRvA6
} j
uA@"SG
\c<
oVF'
CountControl.java fF(2bVKP:
zm"
/* RbAl_xKI
* CountThread.java eV[{c %wN:
* %MeAa?G-#
* Created on 2007年1月1日, 下午4:57 jE\G_>
* m/KaWrw/)
* To change this template, choose Tools | Options and locate the template under BNfj0e 5b
* the Source Creation and Management node. Right-click the template and choose )`DVPudiy
* Open. You can then make changes to the template in the Source Editor. HwUaaK
*/ yQ$irS?
ppyy0E^M
package com.tot.count; ~_\Ra%
import tot.db.DBUtils; S6<o?X9,I
import java.sql.*; ] pn
U"
/** u?=mh`
* x>yqEdR=o
* @author %Mda<3P
*/ 1dQAo1
public class CountControl{ Qr.{_M
private static long lastExecuteTime=0;//上次更新时间 )A8#cY!<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 b`jR("U
/** Creates a new instance of CountThread */ :_8K8Sa
public CountControl() {} rNP;53FtZl
public synchronized void executeUpdate(){ ZcN0:xU
Connection conn=null; C/k#gLF`
PreparedStatement ps=null; Kh]es,$D
try{ #a e@VedM
conn = DBUtils.getConnection(); q+?&w'8
conn.setAutoCommit(false); a*P v^Np-v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >C0B!MT?3%
for(int i=0;i<CountCache.list.size();i++){ 16iTE-J_
CountBean cb=(CountBean)CountCache.list.getFirst(); 7Qd4L.
CountCache.list.removeFirst(); JW
D`}
ps.setInt(1, cb.getCountId()); y%TqH\RKv
ps.executeUpdate();⑴ kR<sSLEb
//ps.addBatch();⑵ f2WVg;Z
} aTvyzr1
//int [] counts = ps.executeBatch();⑶ C'JI%HnQ
conn.commit(); TO6F
}catch(Exception e){ =XfvPBA
e.printStackTrace(); o?baiOkH
} finally{ w
<r*&
try{ +(+lbCW/
if(ps!=null) { Wg|6{'a
ps.clearParameters(); REh"/d
ps.close(); ;jzJ6~<
ps=null; K*@?BE
} 56Wh<i3
}catch(SQLException e){} 8{>|%M
DBUtils.closeConnection(conn); n{?Du
} V%R]jbHZ#
} -'&l!23a~
public long getLast(){ mI&3y9; (
return lastExecuteTime; o,i_py
} fbApE
public void run(){ YEv\!%B
long now = System.currentTimeMillis(); If&))$7u
if ((now - lastExecuteTime) > executeSep) { fzJiW@-T
//System.out.print("lastExecuteTime:"+lastExecuteTime); @/#G2<Vp1
//System.out.print(" now:"+now+"\n"); h4n~V:nNm
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); AROHe
lastExecuteTime=now; ToHx!,tDS
executeUpdate(); MV5$e
} 5RT#H0/+
else{ D1RQkAZS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); |j+JLB
} !zK"y[V
} ui?@:=
} ]-wyZ +a
//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 )u(,.O[cw
r*{.|>me
类写好了,下面是在JSP中如下调用。 7{r7
~BI`{/O=
<% 94!}
Z>
CountBean cb=new CountBean(); _N5pxe`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 27Gff(
CountCache.add(cb); =ls+vH40&
out.print(CountCache.list.size()+"<br>"); JrBPx/?(,;
CountControl c=new CountControl(); Yup#aeXY/
c.run(); tar/n o
out.print(CountCache.list.size()+"<br>"); R&!;(k0
%>