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: :otY;n -
V5u}C-o
CountBean.java vLBee>$
\,l.p_<
/* 8|5Gv
* CountData.java oEenm\ZI
* yE.495
* Created on 2007年1月1日, 下午4:44 )l#%.Z9
* :Hzz{'
* To change this template, choose Tools | Options and locate the template under w>6"Sc7oc2
* the Source Creation and Management node. Right-click the template and choose pHj[O?F
* Open. You can then make changes to the template in the Source Editor. nIyROhZ
*/ '&-5CpDUs
#QTfT&m+G}
package com.tot.count; AaVI%$
jr,&=C(
/** DJViy
* "ep `
* @author mq
J0z4I}
*/ .'^6QST
public class CountBean { pcI&
private String countType; M<{5pH(K
int countId; ! fi &@k
/** Creates a new instance of CountData */ 9h:jFhsA9
public CountBean() {} lh,ylh
public void setCountType(String countTypes){ ?iPZsV
this.countType=countTypes; A6^p}_
} E!zd(
public void setCountId(int countIds){ &/>;LgN
this.countId=countIds; 0" U5oP[
} "UQr :/
public String getCountType(){ Gur8.A;Y
return countType; V[o7Jr~
} UAsF0&]
public int getCountId(){ [&h#iTRT
return countId; Io$w|~x
} ZnvEv;P
} V!T^wh;
'}jf#C1$c
CountCache.java BIxV|\k
_M8G3QOx
/* :3KO6/+
* CountCache.java 3]O`[P,*%
* IL~]m?'V(
* Created on 2007年1月1日, 下午5:01 P0%N
Q1bn
* MU_!&(X_
* To change this template, choose Tools | Options and locate the template under S}oG.r
9
* the Source Creation and Management node. Right-click the template and choose )-bD2YA{
* Open. You can then make changes to the template in the Source Editor. 5h`m]#YEG
*/ NuC-qG#
%f3c7\=C
package com.tot.count; *Q bM*oH
import java.util.*; Pm$F2YrO3
/** FU_fCL8yA
* t8+?U^j
* @author LP.HS'M~u
*/ Sm$p\ORa
public class CountCache { 2y3?!^$
public static LinkedList list=new LinkedList(); O&`U5w
/** Creates a new instance of CountCache */ x96qd%l/
public CountCache() {} f{)+-8
public static void add(CountBean cb){ +7| [b
if(cb!=null){ /xl4ohL$a
list.add(cb); .)LZ`Ge3F
} vuYO\u+ud
} 7JbY}@
} 3p:=xL
<+V-k|
CountControl.java jCU=+b=
\Dn&"YG7
/* B4`2.yRis
* CountThread.java qBT_!
)h
* &MCy.(jN
* Created on 2007年1月1日, 下午4:57 L +L9Y}
* ;tJWOm
* To change this template, choose Tools | Options and locate the template under :]vA2
* the Source Creation and Management node. Right-click the template and choose iV5}U2Vh
* Open. You can then make changes to the template in the Source Editor. 8O,?|c=>
*/ "hL9f=w
{DU"]c/S
package com.tot.count; ^#]c0
import tot.db.DBUtils; ?nQ_w0j
import java.sql.*; _b>F#nD,'%
/** *i@sUM?K
* ,Z^Ca15z
* @author eymi2-a<
*/ ? m&IF<b
public class CountControl{ :.Y|I[\E%
private static long lastExecuteTime=0;//上次更新时间 he"L*p*H
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 O/mR9[}
/** Creates a new instance of CountThread */ F "!agc2!
public CountControl() {} \Ke8W,)ew
public synchronized void executeUpdate(){ yH*hL0mO
Connection conn=null; TYYp"wx
PreparedStatement ps=null; G 0hYFc u
try{ +a|"{
conn = DBUtils.getConnection(); zJ5hvDmC
conn.setAutoCommit(false); X4a^mw\"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }i(qt&U;
for(int i=0;i<CountCache.list.size();i++){ 5?Bc
Y;
CountBean cb=(CountBean)CountCache.list.getFirst(); ! 0^;;'
CountCache.list.removeFirst(); fV 3r|Bp
ps.setInt(1, cb.getCountId()); ^V[/(Lq
ps.executeUpdate();⑴ )CJES!!
W
//ps.addBatch();⑵ M&r2:Whk
} 1Q]Rd
//int [] counts = ps.executeBatch();⑶ |+98h&U~
conn.commit(); cgyp5\*>+
}catch(Exception e){ K4C^m|e
e.printStackTrace(); |pJC:woq
} finally{ ',GV6kt_k
try{ ~8TF*3[}[
if(ps!=null) { sI'a1$
ps.clearParameters(); qpI]R
ps.close(); u#1%P5r&X
ps=null; S.{fDcM
} k}GjD2m
}catch(SQLException e){} 3QW_k5o
DBUtils.closeConnection(conn); ]fZ<`w8u}
} |XRImeF'd
} v,{h:
public long getLast(){ KF_ ?'X0=
return lastExecuteTime; f-4.WW2FN
} +td<{4oq8
public void run(){ F+m[&MKL
long now = System.currentTimeMillis(); -IadHX}]t
if ((now - lastExecuteTime) > executeSep) { n@hl2M6.x9
//System.out.print("lastExecuteTime:"+lastExecuteTime); >L gVj$Z
//System.out.print(" now:"+now+"\n"); xRlYr# %
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /Y,r@D
lastExecuteTime=now; F|Q H
executeUpdate(); 3V?817&6z
} yG\UW&P
else{ 1]T|6N?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /%!~x[BeJ>
} e'34Pw!m
} Pe}PH
I
} gw^'{b
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 V>Fesm"aq
%t*[T
类写好了,下面是在JSP中如下调用。 ~h!
13!
Hy]
<% zzJja/mp
CountBean cb=new CountBean(); vg)Z]F=t(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >^=gDJ\a
CountCache.add(cb); ~M5:=zKQ
out.print(CountCache.list.size()+"<br>"); %m eLW&
CountControl c=new CountControl(); ?DPHo)w
c.run(); Z.'syGuV
out.print(CountCache.list.size()+"<br>"); dQD$K|aUp
%>