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: [E|uY]DR
cbYK5fj"T
CountBean.java (s&&>M]r_
?JXa~.dA
/*
#^0(
* CountData.java g)1X&>
* dYF=c
* Created on 2007年1月1日, 下午4:44 %u!b& 5]e
* !MV@)
(.
* To change this template, choose Tools | Options and locate the template under W5 ec
* the Source Creation and Management node. Right-click the template and choose suVmg-d
* Open. You can then make changes to the template in the Source Editor. FFvCi@oT
*/ NBOCt)C;H
r4Q|5kT*i
package com.tot.count; S|AjL
Ng#
O|'1B>X
/** Ll}yJ#3,
* K 1W].(-@4
* @author KY.ZT2k
*/ 76@qHTh}
public class CountBean { H=~9CJ+tc
private String countType; f~ U.a.Fb
int countId; >5ChcefH
/** Creates a new instance of CountData */ ,;jGJr
public CountBean() {} 8ObeiVXf)
public void setCountType(String countTypes){ f^b K=#
this.countType=countTypes; r*XLV{+4
} N$#\Xdo
public void setCountId(int countIds){ iqPBsIW
this.countId=countIds; uQ3[Jz`y
} 4 b,N8
public String getCountType(){ #g9ZX16}
return countType; |He=LQ}0
} "rNL
`P7
public int getCountId(){ ]?K.
S6
return countId; Z^ar.boc
} |.U)ll(c
} Adx`8}N8
$/Ov2z
CountCache.java L:R<e#kgS
\#Up|u:
/* DL8x":;
* CountCache.java 8Vn4.R[vE
* 7o]HQ[ xO
* Created on 2007年1月1日, 下午5:01 )jDJMi_[
* 'jfRt-_-
* To change this template, choose Tools | Options and locate the template under j-b* C2l
* the Source Creation and Management node. Right-click the template and choose &c%Y<1e`%
* Open. You can then make changes to the template in the Source Editor. K7(MD1tk
*/ r>t1 _b+nu
,wj"! o#
package com.tot.count; C+N k"l9
import java.util.*; Qa4MZj;$K
/** EgM*d)X
* j6YiE~
* @author ]?LB?:6
*/ zP) ~a
public class CountCache { iiC!|`k"
public static LinkedList list=new LinkedList(); D4u%6R|F
/** Creates a new instance of CountCache */ A :e;k{J
public CountCache() {} S#l5y%&
public static void add(CountBean cb){ p]T"|! d
if(cb!=null){ jvwwJ<K
list.add(cb); {?8B,G2r
} 7E7dSq
} @cD uhK"U}
} *?%
k#S
.~D>5 JnEk
CountControl.java !8Rw O%c(
I4c!m_sr
/* <L0#O(L
* CountThread.java r4XH =
* 0L-!!
c3
* Created on 2007年1月1日, 下午4:57 5iX!
lAFJ
* cP>o+-)
* To change this template, choose Tools | Options and locate the template under m$2<`C=
* the Source Creation and Management node. Right-click the template and choose q1{H~VSn"
* Open. You can then make changes to the template in the Source Editor. .*/Fucr
*/ nk=$B(h
\2e0|)aF6
package com.tot.count; elPE%'
import tot.db.DBUtils; S::>N.y
import java.sql.*; $)Bg JDr
/** \_BkY%a
* ;H0 {CkH
* @author ko\):DN
*/ Gc,_v3\
public class CountControl{ 7jG(<!,
private static long lastExecuteTime=0;//上次更新时间 ROb\Rxm
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 19U]2D/z
/** Creates a new instance of CountThread */ !{%: qQiA
public CountControl() {} $jzFc!rs
public synchronized void executeUpdate(){ hZ$t$3
Connection conn=null; dp5cDF}l
PreparedStatement ps=null; ku&k'V
try{
``K#}3
conn = DBUtils.getConnection(); Xyx"A(v^l
conn.setAutoCommit(false); ~Ci{3j :]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); iz[gHB
for(int i=0;i<CountCache.list.size();i++){ A#y@`}]!'
CountBean cb=(CountBean)CountCache.list.getFirst(); r ,(Mu
CountCache.list.removeFirst(); 8p^B hd
ps.setInt(1, cb.getCountId()); H`QQG!
ps.executeUpdate();⑴ k!L@GQ
//ps.addBatch();⑵ zTm]AG|0
} ^A_;#vK
//int [] counts = ps.executeBatch();⑶ %&<LNEiUN
conn.commit(); (P|pRVO
}catch(Exception e){ !nf-}ze{
e.printStackTrace(); ?&+9WJ<M
} finally{ :!TIK1
try{ FY3IUG
if(ps!=null) { ]$iqa"{
ps.clearParameters(); #1nJ(-D+
ps.close(); _2ef LjXQ
ps=null; $.E6S<(h
} 2t#L:vY
}catch(SQLException e){} 'DbMF?<.
DBUtils.closeConnection(conn); %VNlXHO.
} r7mD{0s*
} ",qU,0
public long getLast(){ KW3+luI6
return lastExecuteTime; Li{~=S@N*
} 2[yBD-":
public void run(){ N:5[,O<m_
long now = System.currentTimeMillis(); |UUdz_i!:
if ((now - lastExecuteTime) > executeSep) { r?$?;%|C
//System.out.print("lastExecuteTime:"+lastExecuteTime); w}cY6O,1
//System.out.print(" now:"+now+"\n"); dFXc/VH')
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); W7No ls{
lastExecuteTime=now; ki]ti={12
executeUpdate(); k ]a*&me
} 9)dfL?x8V{
else{ $%k1fa C
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ib6^x:HGU
} AONDx3[
} 2'0K WYM
} a:STQk V
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 |AZW9
io2)1cE&f
类写好了,下面是在JSP中如下调用。 R!\EKH
3,X/,'
<% :Ixx<9c.
CountBean cb=new CountBean(); 9"{W,'r&d
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^ZRYRA
CountCache.add(cb); W6c]-pc
out.print(CountCache.list.size()+"<br>"); [#^#+ |{\
CountControl c=new CountControl(); E>jh"|f:{
c.run(); a}yXC<}$
out.print(CountCache.list.size()+"<br>"); &dB-r&4;+
%>