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: /8GdCac
%bnXZA2Sx
CountBean.java svpQ.Q
H<d~AurX)J
/* 7d;|?R-8D
* CountData.java HzTmNm)
* ,AnD%#o
* Created on 2007年1月1日, 下午4:44 w/|&N>ZOx
* K6DN>0sY
* To change this template, choose Tools | Options and locate the template under =|oi0
* the Source Creation and Management node. Right-click the template and choose %]+R>+
* Open. You can then make changes to the template in the Source Editor. BqNsW
(+
*/ 6ll!7U(9(
!!C/($
package com.tot.count; 8}|et~7!
U3_${
/** -8l<5g7
* &M13F>!
* @author V\`Z|'WIQD
*/ <r}wQ\F#
public class CountBean { >9H^r\
private String countType; ^_]ZZin
int countId; <Kt_
oxK,
/** Creates a new instance of CountData */ {SV/AN
public CountBean() {} Z"8lW+r*
public void setCountType(String countTypes){
RHUZ:r
this.countType=countTypes; ABCm2$<
} gG?@_ie
public void setCountId(int countIds){ 7P1Pk?pxy
this.countId=countIds; PYCN3s#Gi
} sh
:$J[
public String getCountType(){ #8Bh5L!SJ1
return countType; ?tLApy^`?
} c_>Gl8J
public int getCountId(){ !1l~UB_
return countId; httywa^
} v]k-xn|$j
} a0|hLqI
V_h&9]RL
CountCache.java 1'&.6{)P
Z|t=t"6"
/* JI>Y?1i0O
* CountCache.java $cSUB
* }a;xs};X;
* Created on 2007年1月1日, 下午5:01 B%tF|KKj
* $7q3[skH
* To change this template, choose Tools | Options and locate the template under yXU.PSG*
* the Source Creation and Management node. Right-click the template and choose nQc,^A)I
* Open. You can then make changes to the template in the Source Editor. +4 k=Y
*/ 4Fg2/O_3
x*1wsA
package com.tot.count; z$Jm1l
import java.util.*; P)vD?)Q
/** A|ZT;\
* JX&U?Z
* @author 3L&:
*/ 3m>YR-n$
public class CountCache { 7${<u 0((!
public static LinkedList list=new LinkedList(); 7DAP_C
/** Creates a new instance of CountCache */ w5>[hQR\
public CountCache() {} ||:>&
public static void add(CountBean cb){ RBQ8+^
if(cb!=null){ +(*HDa|
list.add(cb); iwF_'I$#N
} A4"TJZBg}
} @}
Ig*@
} cQEUHhRg!
Qj^Uz+b
CountControl.java CV0id&Nv
Lap?L/NS
/* L"b&O<No
* CountThread.java Bt<)1_
* S)U*1t7[
* Created on 2007年1月1日, 下午4:57 UyRy>:n
* lsax.uG5x
* To change this template, choose Tools | Options and locate the template under ?F05BS#)X
* the Source Creation and Management node. Right-click the template and choose 7eCjp
* Open. You can then make changes to the template in the Source Editor. O h@z<1eYZ
*/ h`6 (Oo|
h7#\]2U$[5
package com.tot.count; <q7o"NI6FZ
import tot.db.DBUtils; m}l);P^
import java.sql.*; <H^jbK
/** GlJ[rD
* {4S UGo>
* @author ~uhW~bT
*/ AMyg>n!
public class CountControl{ 33~MP;
private static long lastExecuteTime=0;//上次更新时间 >` s"C
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 s*PKr6X+
/** Creates a new instance of CountThread */ <1*kXTN(
public CountControl() {} Tf3CyH!k
public synchronized void executeUpdate(){ =f~<*wQ
Connection conn=null; aBC5?V*e%
PreparedStatement ps=null; 4v_Ac;2m&
try{ RZHfT0*jL
conn = DBUtils.getConnection(); s~7a-J
conn.setAutoCommit(false); RL}?.'!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); OJm ]gb7
for(int i=0;i<CountCache.list.size();i++){ @\?HlGWEf
CountBean cb=(CountBean)CountCache.list.getFirst(); /5sn*,
CountCache.list.removeFirst(); {8.Zb NEJ
ps.setInt(1, cb.getCountId()); FxlH;'+Q
ps.executeUpdate();⑴ /NQrE#pb
//ps.addBatch();⑵ 2G8w&dtu
} Y#@D%
a 8
//int [] counts = ps.executeBatch();⑶ t~L4wr{B
conn.commit(); J_7w_T/
}catch(Exception e){ E`j' <#V!
e.printStackTrace(); `"=Hk@E
} finally{ %6q82}# `
try{ ejd_ 85$
if(ps!=null) { $2uC%er"H
ps.clearParameters(); myj/93p}`b
ps.close(); Z#}sK5s
ps=null; %UI^+:C
} j/aJD E(+
}catch(SQLException e){} kEh\@x[
DBUtils.closeConnection(conn); yhKH}
kR
} uUjjAGZ
} u.yR oZ8/!
public long getLast(){ U$5x#{AFp
return lastExecuteTime; J?V$V
>d
} 2B4.o*Q\
public void run(){ TyV~2pcN
long now = System.currentTimeMillis(); {H/%2
if ((now - lastExecuteTime) > executeSep) { I7_8oq\3D
//System.out.print("lastExecuteTime:"+lastExecuteTime); k<1i.rh
//System.out.print(" now:"+now+"\n"); 2{j$1EdI@-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); _|\X8o_
lastExecuteTime=now; 0f5 ag&
executeUpdate(); W/UA%We3+L
} >T;!Z 5L1
else{ $TK*w8@:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); z6w'XA1_+t
} bhD-;Y!6;
} !Q"L)%)'A
} L,R}l0kc
//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 6 ZRc|ZQ
\~8W0q.4M
类写好了,下面是在JSP中如下调用。 dCo)en
U nDCC_ud
<% p
l^;'|=M
CountBean cb=new CountBean(); :WRD<D_4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); uzxwJs'fz
CountCache.add(cb); = 9Yfo,F
out.print(CountCache.list.size()+"<br>"); y CHOg
CountControl c=new CountControl(); VKPEoy8H
c.run(); wa,`BAKJ+F
out.print(CountCache.list.size()+"<br>"); *w;?&)8%
%>