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: phB d+zQc
h)aLq
CountBean.java 1^ iLs
_Fe=:q
/* Qz"//=hC|H
* CountData.java 0#ON}l)>
* GIfs]zVr`
* Created on 2007年1月1日, 下午4:44 Z-yoJZi
* 5kA D vi.
* To change this template, choose Tools | Options and locate the template under 5DO}&%.xt
* the Source Creation and Management node. Right-click the template and choose Vy^mEsQC+h
* Open. You can then make changes to the template in the Source Editor.
@1U6sQ
*/ [z6P]eC7
:Zo^Uc:*w
package com.tot.count; b<[]z,
eR/X9<
/** {Z1-B60P
* %d<UMbS^
* @author LR'~:46#u
*/ ,Ek6X)|@
public class CountBean { 19RbIG/X
private String countType; %IDl+_j
int countId; (`u+(M!^
/** Creates a new instance of CountData */ .4[M-@4+]
public CountBean() {} ylDfr){
public void setCountType(String countTypes){ @}uo:b:Q
this.countType=countTypes; 44KWS~
} j&b<YPZ
public void setCountId(int countIds){ _Y$v=!fY&
this.countId=countIds; <p +7,aE_
} RWoVN$i>
public String getCountType(){ }=.C~f]A
return countType; P ?96;
} 7HL23Vrk
public int getCountId(){ O2fFh_\
return countId; *Wcq'S
} aC<fzUD;
} jpOcug`f
F=f9##Y?7M
CountCache.java )i\foSbB`V
ldc`Y/:{
/* (a~V<v"
* CountCache.java Yp8XZ3
* ,mK UCG
* Created on 2007年1月1日, 下午5:01 1^[]#N-Bu
* =/ \l=*
* To change this template, choose Tools | Options and locate the template under *OHjw;xm+
* the Source Creation and Management node. Right-click the template and choose &(jt|?{
* Open. You can then make changes to the template in the Source Editor. zy~*~;6tW
*/ ^K
9jJS9K
iR8;^C.aT
package com.tot.count; 5bsv05=e
import java.util.*; 3M'Y'Szm
/** ej&o,gX
* o =F!&]+
* @author <l>L8{-3
*/ E/D@;Ym18
public class CountCache { 3wfJ!z-E8
public static LinkedList list=new LinkedList(); yA`,ns&n
/** Creates a new instance of CountCache */ :K(+ KN(
public CountCache() {} 2d<`dQY{l3
public static void add(CountBean cb){ Xob(4
if(cb!=null){ D2io3Lo$ov
list.add(cb); 1KJ[&jS ]
} G {a;s-OA3
} 5RY rAzQo
} 1 -R4A7+3
|Z$)t%'
CountControl.java MW=rX>tE
tMo=q7ig
/* APU~y5vG (
* CountThread.java k_Lv\'Ok
* ^Nysx ~6
* Created on 2007年1月1日, 下午4:57 "tj]mij2)G
* [.;8GMW
* To change this template, choose Tools | Options and locate the template under cl M6R
* the Source Creation and Management node. Right-click the template and choose Kn2W{* wD
* Open. You can then make changes to the template in the Source Editor. P%<MQg|k`
*/ Ac/LNqIs
P_gai7Xg
package com.tot.count; 5o0H7k]
import tot.db.DBUtils; ^HHT>K-m
import java.sql.*; 8P2_/)|
/** :;Npk9P(N
* nrM-\'
* @author fOk(ivYy
*/ b'RBel;W
public class CountControl{ 0iz\<'
p
private static long lastExecuteTime=0;//上次更新时间 7qdB
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 }c#W"y5l_
/** Creates a new instance of CountThread */ t /lU*
public CountControl() {} pz.fZV
public synchronized void executeUpdate(){ 5)gC<
Connection conn=null; a
JQ_V
PreparedStatement ps=null; jLEO-<)-)
try{ c2d1'l]n
conn = DBUtils.getConnection(); vQ{mEaH
conn.setAutoCommit(false); )xTu|V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R5<:3tk=X
for(int i=0;i<CountCache.list.size();i++){ |lVi* 4za%
CountBean cb=(CountBean)CountCache.list.getFirst(); '/Xm%S
CountCache.list.removeFirst(); gNh4c{Al9
ps.setInt(1, cb.getCountId()); B5]nP .R
ps.executeUpdate();⑴ $- GwNG
//ps.addBatch();⑵ G52z5-=v
} ]YB,K)WQ
//int [] counts = ps.executeBatch();⑶ X\BdN Hr
conn.commit(); % "ZC9uq?
}catch(Exception e){ 6{ pg^K
e.printStackTrace(); jYW-}2L
} finally{ Nh6!h%
try{ a3:1`c/~\
if(ps!=null) { IN"6=2:
ps.clearParameters(); dAjm4F-
ps.close(); /qd~|[Kx:
ps=null; 5"Y:^_8
} `QT9W-0e^
}catch(SQLException e){} o7yvXrpG(U
DBUtils.closeConnection(conn); "}<baz
} P_M!h~
} .?r}3Ch
public long getLast(){ N$cAX^~
return lastExecuteTime; D]K?ntS[*
} |1/?>=dDm
public void run(){ PxJvE*6^H
long now = System.currentTimeMillis(); .y#>mXm>
if ((now - lastExecuteTime) > executeSep) { AHLXmQl
//System.out.print("lastExecuteTime:"+lastExecuteTime); Lx3`.F\mG
//System.out.print(" now:"+now+"\n"); '8|joj>G=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); M+L0 X$}NZ
lastExecuteTime=now; "GAKi}y">v
executeUpdate(); -nB.
.q
} h9 +76
else{ <{.pYrn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :) T#.(mR
} wgZ6|)!0
} IZZ
$p{
} kyUG+M
//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 7nbaR~ZV
4TaHS!9
类写好了,下面是在JSP中如下调用。 A)nE+ec1
{CGk9g"`
<% 'Y>@t6E4
CountBean cb=new CountBean(); `(@{t:L
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); w#;y
CountCache.add(cb); p1,.f&(f
out.print(CountCache.list.size()+"<br>"); Ewo6Q){X
CountControl c=new CountControl(); 4HyD=6V#
c.run(); ZZW%6 -B
out.print(CountCache.list.size()+"<br>"); <rNz&;m}
%>